Photosensitive resin composition, photosensitive element, method for forming resist pattern, and method for producing printed wiring board

Abstract

This photosensitive resin composition contains a binder polymer, a photopolymerizable compound, a photopolymerization initiator, and a sensitizer, and is characterized in that: the binder polymer has a first structural unit derived from acrylic acid, a second structural unit derived from styrene or a styrene derivative, and a third structural unit derived from a (meth) acrylate compound; the content of the first structural unit is 9-25% by mass (inclusive), the content of the second structural unit is 61% by mass or more, and the content of the third structural unit is 1-20% by mass (inclusive), based on the total mass of structural units derived from polymerizable monomers constituting the binder polymer.

Description

TECHNICAL FIELD

[0001] The present application relates to a photosensitive resin composition, a photosensitive element, a method for forming a resist pattern, and a method for manufacturing a printed wiring board. BACKGROUND

[0002] In the field of manufacturing a printed wiring board, as a resist material used in etching treatment or plating treatment, a photosensitive resin composition and a photosensitive element provided with a layer (hereinafter, also referred to as "photosensitive layer") formed on a support film using the photosensitive resin composition can be widely used.

[0003] A printed wiring board is manufactured using the above-described photosensitive element, for example, according to the following steps. That is, first, the photosensitive layer of the photosensitive element is laminated on a circuit-forming substrate such as a copper-clad laminate. Next, the photosensitive layer is exposed through a mask or the like to form a photocured portion. At this time, the support film is peeled off before or after exposure. Then, a developing solution is used to remove a region other than the photocured portion of the photosensitive layer, and a resist pattern is formed. Next, the resist pattern is used as a resist, and etching treatment or plating treatment is performed to form a conductor pattern, and finally, the photocured portion (resist pattern) of the photosensitive layer is peeled off (removed).

[0004] With the progress of high-density and miniaturization of conductor patterns of a printed wiring board, the contact area of a circuit-forming substrate with the photosensitive layer as a resist becomes small. Therefore, the photosensitive layer is required to have excellent characteristics at the time of etching treatment or plating treatment, and is required to have excellent adhesion to the circuit-forming substrate and excellent resolution at the time of forming a resist pattern (for example, refer to Patent Documents 1 and 2).

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2009-003177

[0008] Patent Document 2: Japanese Patent Application Publication No. 2013-195712 SUMMARY

[0009] Technical Problem to be Solved by the Invention

[0010] With the high performance of semiconductor packages, the smoothness of substrates and the miniaturization of wiring are also developing, and the photosensitive resin composition is required to form a resist pattern having high adhesion that can form fine wiring. On the other hand, with the photosensitive resin composition having excellent adhesion, the peeling time of the resist pattern tends to be long. From the viewpoint of improving productivity, it is desirable that the photosensitive resin composition can shorten the peeling time.

[0011] An object of the present application is to provide a photosensitive resin composition capable of balancing adhesiveness and peeling properties, a photosensitive element, a method for forming a resist pattern, and a method for manufacturing a printed wiring board.

[0012] Means for solving technical problems

[0013] The present inventors have found that a photosensitive resin composition capable of forming a resist pattern having excellent adhesiveness and capable of shortening the peeling time of the resist pattern can be obtained by using a binder polymer having a specific composition. One embodiment of the present application relates to a photosensitive resin composition, a photosensitive element, a method for forming a resist pattern, and a method for manufacturing a printed wiring board.

[0014] [1] A photosensitive resin composition comprising a binder polymer, a photopolymerizable compound, a photopolymerization initiator, and a sensitizer, wherein the binder polymer has a first structural unit derived from acrylic acid, a second structural unit derived from styrene or a styrene derivative, and a third structural unit derived from a (meth)acrylate compound, the content of the first structural unit is 9% by mass or more and 25% by mass or less, the content of the second structural unit is 61% by mass or more, and the content of the third structural unit is 1% by mass or more and 20% by mass or less, based on the total mass of the structural units derived from the polymerizable monomers constituting the binder polymer.

[0015] [2] The photosensitive resin composition according to the above [1], wherein

[0016] The solubility parameter of the (meth)acrylate compound is 15.7 to 18.7.

[0017] [3] The photosensitive resin composition according to the above [1] or [2], wherein

[0018] The acid value of the binder polymer is 146 to 180 mgKOH / g.

[0019] [4] The photosensitive resin composition according to any one of the above [1] to [3], wherein

[0020] The glass transition temperature of the binder polymer is 90 to 120°C.

[0021] [5] The photosensitive resin composition according to any one of the above [1] to [4], wherein

[0022] The weight average molecular weight of the binder polymer is 25,000 to 55,000.

[0023] [6] A photosensitive element comprising a support and a photosensitive layer formed on the support using the photosensitive resin composition according to any one of the above [1] to [5].

[0024] [7] A method for forming a resist pattern, comprising: a step of forming a photosensitive layer on a substrate using the photosensitive resin composition according to any one of the above-mentioned [1] to [5] or the photosensitive element according to the above-mentioned [6]; a step of forming a photocured portion by irradiating active light to at least a part of the photosensitive layer; and a step of removing a non-photocured portion of the photosensitive layer from the substrate to form a resist pattern.

[0025] [8] A method for manufacturing a printed wiring board, comprising a step of forming a conductor pattern by performing etching treatment or plating treatment on a substrate on which a resist pattern is formed by the method for forming a resist pattern according to the above-mentioned [7].

[0026] [9] The method for manufacturing a printed wiring board according to the above-mentioned [8], further comprising a step of removing the resist pattern after the etching treatment or the plating treatment.

[0027] Effects of the Invention

[0028] According to the present application, it is possible to provide a photosensitive resin composition, a photosensitive element, a method for forming a resist pattern, and a method for manufacturing a printed wiring board, which can balance adhesiveness and peelability. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a schematic cross-sectional view showing an embodiment of a photosensitive element. DETAILED DESCRIPTION

[0030] In the present specification, the term "step" includes not only a single step, but also a range where the intended function of the step is achieved, even if the step cannot be clearly distinguished from other steps. With respect to the term "layer", a structure in which a shape is formed on a part, in addition to a structure in which a shape is formed on an entire surface, is included when viewed in a plan view. A numerical range indicated using "~" indicates a range including numerical values recited before and after "~" as minimum and maximum values, respectively. In the present specification, an upper limit value or a lower limit value of a numerical range recited at a certain stage can be replaced with an upper limit value or a lower limit value of a numerical range recited at another stage. In the present specification, an upper limit value or a lower limit value of a numerical range can be replaced with a value shown in the examples.

[0031] In the present specification, "(meth)acrylate" means at least one of "acrylate" and "methacrylate" corresponding thereto. The same applies to other similar expressions such as "(meth)acryl".

[0032] In the present specification, regarding the amount of each component in the photosensitive resin composition, in the case where a plurality of substances belonging to each component is present in the composition, the total amount of the plurality of substances present in the composition is meant unless otherwise specified. In the present specification, the "solid content" means the non-volatile component in the photosensitive resin composition excluding the volatile substances (water, solvents, etc.). That is, the "solid content" means the component other than the solvent which does not volatilize and remains in the drying of the photosensitive resin composition described later, and also includes the component which is liquid, syrup-like or wax-like at room temperature (25°C).

[0033] [Photosensitive resin composition]

[0034] The photosensitive resin composition according to the present embodiment contains (A) a binder polymer (hereinafter, sometimes referred to as "(A) component"), (B) a photopolymerizable compound (hereinafter, sometimes referred to as "(B) component"), (C) a photopolymerization initiator (hereinafter, sometimes referred to as "(C) component"), and (D) a sensitizer (hereinafter, sometimes referred to as "(D) component"). The binder polymer described above has a first structural unit derived from acrylic acid, a second structural unit derived from styrene or a styrene derivative, and a third structural unit derived from a (meth)acrylate compound, the content of the first structural unit is 9 mass% or more and 25 mass% or less, the content of the second structural unit is 61 mass% or more, and the content of the third structural unit is 1 mass% or more and 20 mass% or less, based on the total mass of the structural units derived from the polymerizable monomers constituting the binder polymer. Hereinafter, each component which the photosensitive resin composition can contain will be described in detail.

[0035] ((A) component: binder polymer)

[0036] The photosensitive resin composition according to the present embodiment can improve the adhesion and the peelability of the photosensitive layer formed from the photosensitive resin composition by containing the binder polymer having a specific structure as the (A) component.

[0037] The (A) component can be produced by subjecting the polymerizable monomers including acrylic acid, styrene or a styrene derivative, and a (meth)acrylate compound to radical polymerization.

[0038] By having the (A) component have the first structural unit derived from acrylic acid, the alkali developability of the photosensitive resin composition can be improved, and the peelability of the resist pattern can be improved.

[0039] From the viewpoint of further shortening the development time, the content of the first structural unit in the (A) component can be 9% by mass or more, 15% by mass or more, 16% by mass or more, 17% by mass or more, 18% by mass or more, or 19% by mass or more, based on the total mass of the structural units derived from the polymerizable monomers constituting the binder polymer (100% by mass). From the viewpoint of further improving the adhesion, the content of the first structural unit can be 25% by mass or less, 24% by mass or less, or 23.5% by mass or less. From the viewpoint of balancing the development and the adhesion, the content of the structural unit derived from acrylic acid can be 15 to 25% by mass, 16 to 25% by mass, 17 to 24% by mass, 18 to 24% by mass, or 19 to 23.5% by mass.

[0040] By having the (A) component have the second structural unit derived from styrene or a styrene derivative, it is possible to improve the resolution and the adhesion of the photosensitive resin composition. As the styrene derivative, for example, vinyltoluene, α-methylstyrene, p-methylstyrene, and p-ethylstyrene can be given.

[0041] From the viewpoint of further improving the adhesion, the content of the second structural unit in the (A) component can be 61% by mass or more, 62% by mass or more, 64% by mass or more, or 66% by mass or more, based on the total mass of the structural units derived from the polymerizable monomers constituting the binder polymer. From the viewpoint of further shortening the peeling time, the content of the second structural unit can be 85% by mass or less, 84% by mass or less, 83% by mass or less, or 80% by mass or less. From the viewpoint of balancing the adhesion and the peeling, the content of the structural unit derived from styrene or a styrene derivative can be 61 to 85% by mass, 62 to 84% by mass, 64 to 83% by mass, or 66 to 80% by mass.

[0042] By having the (A) component have the third structural unit derived from a (meth)acrylate compound, it is possible to adjust the balance between the adhesion and the peeling of the photosensitive resin composition.

[0043] From the viewpoint of further shortening the peeling time, the content of the third structural unit in the (A) component can be 2% by mass or more, 2.5% by mass or more, or 3% by mass or more, based on the total mass of the structural units derived from the polymerizable monomers constituting the binder polymer. From the viewpoint of further improving the adhesion, the content of the third structural unit can be 19% by mass or less, 18% by mass or less, or 16% by mass or less. From the viewpoint of balancing the adhesion and the peeling, the content of the structural unit derived from a (meth)acrylate compound can be 2 to 19% by mass, 2.5 to 18% by mass, or 3 to 16% by mass.

[0044] As the (meth)acrylate compound, a (meth)acrylate compound having a solubility parameter of 15.7 to 18.7 is preferably used. From the viewpoints of resolution and adhesiveness, the solubility parameter of the (meth)acrylate compound can be 15.8 to 18.6, 16.0 to 18.5, or 16.5 to 18.4.

[0045] The solubility parameter (δD) of the polymerizable monomer can be calculated using HSPiP software. HSPiP is software specialized for calculating Hansen solubility parameters. It is considered that δD affects the interaction of the structural units constituting the binder polymer.

[0046] As the (meth)acrylate compound, a (meth)acrylate compound having a logarithm value of octanol / water partition coefficient (logP) of 0.5 or more can be used. From the viewpoint of improving resolution and adhesiveness, the logP of the (meth)acrylate compound can be 1.0 or more, 2.0 or more, or 3.0 or more, and from the viewpoint of making the developability good, can be 12.0 or less, 10.0 or less, or 6.0 or less.

[0047] The logP of the polymerizable monomer can be calculated using COSMOtherm (registered trademark), for example. COSMOtherm is thermodynamic property calculation software using the COSMO-RS method. The COSMO-RS method is a method of calculating the properties of chemical substances based on the molecular surface charge obtained by quantum chemical calculation. The logP is an index indicating the hydrophilicity of the structural units constituting the binder polymer.

[0048] As the (meth)acrylate compound, for example, (meth)acrylic acid-2-hydroxypropyl ester, mono-2-(methacryloyloxy)ethyl phthalate, (meth)acrylic acid hydroxyethyl ester, (meth)acryloyl morpholine, dicyclopentyl (meth)acrylate, p-diphenyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, and isostearyl (meth)acrylate can be given.

[0049] The (A) component can further contain a structural unit derived from a polymerizable monomer other than the above (hereinafter, also referred to as "other monomer"). As the other monomer, for example, benzyl (meth)acrylate or a derivative thereof, furfuryl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, glycidyl (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3-tetrafluoropropyl (meth)acrylate, β-furyl (meth)acrylic acid, β-styryl (meth)acrylic acid, maleic acid, maleic anhydride, maleic acid monoalkyl ester, fumaric acid, cinnamic acid, α-cyanocinnamic acid, itaconic acid, crotonic acid, and propynoic acid can be given. These can be used alone or in combination of two or more.

[0050] The weight average molecular weight (Mw) of the (A) component can be 25,000 to 55,000, 30,000 to 53,000, 32,000 to 50,000, or 35,000 to 48,000. When the Mw is 55,000 or less, there is a tendency for resolution and developability to further improve, and when the Mw is 25,000 or more, there is a tendency for defects in the resist pattern to occur and for peeling to be difficult. The dispersity (Mw / Mn) of the (A) component can be 1.0 to 3.0, 1.0 to 2.5, or 1.0 to 2.3. When the dispersity is decreased, there is a tendency for resolution to improve.

[0051] The Mw and Mn can be determined, for example, by gel permeation chromatography (GPC) using a calibration curve for standard polystyrene. More specifically, the determination can be performed under the conditions described in the examples.

[0052] From the viewpoint of both developability and peeling properties, the acid value of the (A) component can be 146 to 180 mgKOH / g, 148 to 178 mgKOH / g, or 150 to 176 mgKOH / g. By having an acid value of 146 mgKOH / g or more for the (A) component, it is easy to further shorten the development time, and by having an acid value of 180 mgKOH / g or less, it is easy to further improve adhesion. The acid value of the (A) component can be adjusted by the structural units derived from acrylic acid. The acid value of the (A) component can be determined according to JIS K6901:2008 5.3.2.

[0053] From the viewpoints of resolution or adhesion, the glass transition temperature (Tg) of the (A) component can be 70 to 125°C, 90 to 120°C, 94 to 110°C, or 96 to 108°C. The Tg of the (A) component is a value calculated according to the formula of Fox from the mass of each polymerizable monomer constituting the (A) component and the Tg of the homopolymer of the each polymerizable monomer.

[0054] The content of the (A) component relative to the total amount of the (A) component and the (B) component, 100 parts by mass, can be 20 parts by mass or more, 30 parts by mass or more, or 40 parts by mass or more, or 50 parts by mass or more, from the viewpoint of excellent film formability, and can be 80 parts by mass or less, 70 parts by mass or less, or 60 parts by mass or less, from the viewpoint of further improving sensitivity and resolution.

[0055] ((B) component: photopolymerizable compound)

[0056] As the (B) component, there is no particular limitation as long as it is a compound having at least one ethylenic unsaturated bond and is photopolymerizable. From the viewpoints of improving alkali developability, resolution, and peeling properties after curing,

[0057] The component (B) preferably contains at least one bisphenol type (meth)acrylate, more preferably contains a bisphenol A type (meth)acrylate.

[0058] As the bisphenol A type (meth)acrylate, for example, 2,2-bis(4-((meth)acryloyloxy polyethoxy)phenyl)propane, 2,2-bis(4-((meth)acryloyloxy polypropoxy)phenyl)propane, 2,2-bis(4-((meth)acryloyloxy polybutoxy)phenyl)propane, and 2,2-bis(4-((meth)acryloyloxy polyethoxy polypropoxy)phenyl)propane can be given. Among them, from the viewpoint of further improving the resolution and the peeling properties, 2,2-bis(4-((meth)acryloyloxy polyethoxy)phenyl)propane is preferred.

[0059] As the 2,2-bis(4-((meth)acryloyloxy polyethoxy)phenyl)propane, a compound having an oxyethylene number of 10 or more, a compound having an oxyethylene number of less than 10, or a combination of a compound having an oxyethylene number of 10 or more and a compound having an oxyethylene number of less than 10 can be used.

[0060] As the commercially available bisphenol A type (meth)acrylate, for example, as 2,2-bis(4-((meth)acryloyloxy dipropoxy)phenyl)propane, BPE-200 (manufactured by SHIN-NAKAMURA CHEMICAL CO., LTD., trade name) can be given, as ethoxylated bisphenol A dimethacrylate, BP-2EM (manufactured by Kyoeisha Chemical Co., Ltd., trade name) can be given, and as 2,2-bis(4-(methacryloyloxy pentaethoxy)phenyl)propane, BPE-500 (manufactured by SHIN-NAKAMURA CHEMICAL CO., LTD., trade name) and FA-321M (manufactured by Resonac Holdings Corporation, trade name) can be given. These bisphenol A type (meth)acrylates can be used alone or in combination of two or more.

[0061] The content of the bisphenol type (meth)acrylate can be 40 to 98% by mass, 50 to 97% by mass, 60 to 95% by mass, or 70 to 90% by mass, based on the total amount of the component (B). When the content is 40% by mass or more, the resolution, the adhesion, and the inhibition of the occurrence of the resist foot become more favorable, and when it is 98% by mass or less, the development time is appropriately shortened, and it is more difficult to generate development residues.

[0062] As the (B) component other than the bisphenol type (meth)acrylate, at least one polyalkylene glycol di(meth)acrylate having at least one of a (poly)oxyethylene chain and a (poly)oxypropylene chain in the molecule can be further included from the viewpoint of improving the flexibility of the cured product (cured film), and a polyalkylene glycol di(meth)acrylate having both of the (poly)oxyethylene chain and the (poly)oxypropylene chain in the molecule can be further included. From the viewpoint of further improving the adhesion and the resolution, the total number of the oxyethylene (EO group) and / or the oxypropylene (PO group) possessed by the polyalkylene glycol di(meth)acrylate can be 2 to 40, 4 to 30, or 6 to 20.

[0063] As the polyalkylene glycol di(meth)acrylate, for example, FA-023M (manufactured by Resonac Holdings Corporation, trade name), FA-024M (manufactured by Resonac Holdings Corporation, trade name), and NK Ester HEMA-9P (manufactured by SHIN-NAKAMURA CHEMICAL CO., LTD., trade name) can be mentioned. These can be used alone or in combination of two or more.

[0064] The content of the polyalkylene glycol di(meth)acrylate can be 2 to 40 mass%, 3 to 30 mass%, or 5 to 20 mass% based on the total amount of the (B) component.

[0065] As the (B) component other than the above, a nonylphenoxy polyethyleneoxy acrylate, a phthalic acid-based compound, a (meth)acrylic acid polyol ester, a (meth)acrylic acid alkyl ester, or the like can also be used. Among them, from the viewpoint of improving the resolution, the adhesion, the resist shape, and the peeling properties after curing in balance, the (B) component can include at least one selected from a nonylphenoxy polyethyleneoxy acrylate and a phthalic acid-based compound. However, the refractive index of these compounds is relatively low, and thus from the viewpoint of improving the resolution, the content thereof can be 5 to 50 mass%, 5 to 40 mass%, or 10 to 30 mass% based on the total amount of the (B) component.

[0066] As the nonylphenoxy polyethyleneoxy acrylate, for example, a nonylphenoxy triethyleneoxy acrylate, a nonylphenoxy tetraethyleneoxy acrylate, a nonylphenoxy pentaethyleneoxy acrylate, a nonylphenoxy hexaethyleneoxy acrylate, a nonylphenoxy heptaethyleneoxy acrylate, a nonylphenoxy octaethyleneoxy acrylate, a nonylphenoxy nonaethyleneoxy acrylate, a nonylphenoxy decaethyleneoxy acrylate, and a nonylphenoxy undecaethyleneoxy acrylate can be mentioned.

[0067] As the phthalic acid-based compound, for example, γ-chloro-β-hydroxypropyl-β'- (methyl)acryloyloxyethyl phthalate, β-hydroxyethyl-β'-(methyl)acryloyloxyethyl phthalate, and β-hydroxypropyl-β'-(methyl)acryloyloxyethyl phthalate can be given. γ-Chloro-β-hydroxypropyl-β'-methylacryloyloxyethyl phthalate is commercially available as FA-MECH (manufactured by Resonac Holdings Corporation, trade name).

[0068] From the viewpoint of improvement in sensitivity and reduction in tailing, the (B) component can contain a (meth)acrylic acid polyol ester. As the (meth)acrylic acid polyol ester, for example, trimethylolpropane polyethoxy tri(meth)acrylate, trimethylolpropane polypropoxy tri(meth)acrylate, trimethylolpropane polybutoxy tri(meth)acrylate, trimethylolpropane polyethoxy polypropoxy tri(meth)acrylate, trimethyloloethane polyethoxy tri(meth)acrylate, trimethyloloethane polypropoxy tri(meth)acrylate, trimethyloloethane polybutoxy tri(meth)acrylate, trimethyloloethane polyethoxy polypropoxy tri(meth)acrylate, pentaerythritol polyethoxy tri(meth)acrylate, pentaerythritol polypropoxy tri(meth)acrylate, pentaerythritol polybutoxy tri(meth)acrylate, pentaerythritol polyethoxy polypropoxy tri(meth)acrylate, glycerol polyethoxy tri(meth)acrylate, glycerol polypropoxy tri(meth)acrylate, glycerol polybutoxy tri(meth)acrylate, and glycerol polyethoxy polypropoxy tri(meth)acrylate can be given.

[0069] The content of the (B) component is preferably set to 20 to 60 parts by mass, more preferably 30 to 55 parts by mass, and further preferably 35 to 50 parts by mass, with respect to 100 parts by mass of the total amount of the (A) component and the (B) component. When the content of the (B) component is within this range, the light sensitivity and the coatability become more favorable in addition to the resolution and the adhesion of the photosensitive resin composition.

[0070] ((C) component: photopolymerization initiator)

[0071] As the (C) component, there is no particular limitation as long as it is a component capable of polymerizing the (B) component, and it can be appropriately selected from the commonly used photopolymerization initiators.

[0072] As the (C) component, for example, a hexaarylbiimidazole compound; a benzophenone compound such as benzophenone, 2-benzyl-2-dimethylamino-l-(4-morpholinophenyl)-l- butanone, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-l-[4-(4-morpholinyl)phenyl]-l- butanone, 4-(2-hydroxyethoxy)phenyl-2-(hydroxy-2-propyl)ketone, 2-methyl-l-[4- (methylthio)phenyl]-2-morpholinopropanone-l, and the like; a quinone compound such as alkylanthraquinone; a benzoin ether compound such as benzyl alkyl ether; a benzoin compound such as benzoin, alkylbenzoin, and the like; a benzyl derivative such as benzyl dimethyl ketal; and a phosphine oxide compound such as bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, bis(2,6-dimethylbenzoyl)-2,4,4-trimethyl-pentylphosphine oxide, (2,4,6-trimethylbenzoyl)ethoxyphenylphosphine oxide, and the like can be given.

[0073] From the viewpoint of improving the adhesion of the photosensitive layer to the smooth substrate, the (C) component can contain a hexaarylbiimidazole compound. The aryl group in the hexaarylbiimidazole compound can be a phenyl group or the like. The hydrogen atom bonded to the aryl group in the hexaarylbiimidazole compound can be substituted with a halogen atom (chlorine atom or the like).

[0074] The hexaarylbiimidazole compound can be a 2,4,5-triarylimidazole dimer. As the 2,4,5-triarylimidazole dimer, for example, 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-bis-(m-methoxyphenyl)imidazole dimer, and 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer can be given.

[0075] The content of the (C) component can be 1.0 to 10 parts by mass, 2.0 to 8 parts by mass, 3.0 to 7.0 parts by mass, or 4.0 to 6.0 parts by mass, relative to 100 parts by mass of the total amount of the (A) component and the (B) component. When the content of the (C) component is within this range, it is easy to improve both the photosensitivity and the resolution in balance.

[0076] ((D) component: sensitizing agent)

[0077] The photosensitive resin composition according to the present embodiment can effectively utilize the absorption wavelength of the active light used in exposure by containing the (D) component.

[0078] As the component (D), for example, a dialkylaminobenzophenone compound, a pyrazoline compound, an anthracene compound, a coumarin compound, a xanthone compound, a thioxanthone compound, an oxazole compound, a benzoxazole compound, a thiazole compound, a benzothiazole compound, a triazole compound, a stilbene compound, a triazine compound, a thiophene compound, a naphthalimide compound, a triarylamine compound, and an aminopyridine compound can be given. From the viewpoint of further improving the resolution and adhesion, the component (D) can contain a pyrazoline compound or a dialkylaminobenzophenone compound.

[0079] Examples of pyrazoline compounds include 1-(4-methoxyphenyl)-3-styrene-5-phenyl-pyrazoline, 1-phenyl-3-(4-methoxyphenyl)-5-(4-methoxyphenyl)-pyrazoline, 1,5-bis-(4-methoxyphenyl)-3-(4-methoxyphenyl)-pyrazoline, 1-(4-isopropylphenyl)-3-styrene-5-phenyl-pyrazoline, 1-phenyl-3-(4-isopropylphenyl)-5-(4-isopropylphenyl)-pyrazoline, 1,5-bis-(4-isopropylphenyl)-3-(4-isopropylphenyl)-pyrazoline, 1-( 4-tert-butyl-phenyl)-3-(4-methoxystyrene)-5-(4-methoxyphenyl)-pyrazoline, 1-(4-isopropyl-phenyl)-3-(4-tert-butyl-styrene)-5-(4-tert-butyl-phenyl)-pyrazoline, 1-(4-tert-butyl-phenyl)-3-(4-isopropyl-styrene)-5-(4-isopropyl-phenyl)-pyrazoline, 1-(4-methoxyphenyl)-3-(4-isopropyl-styrene)-5-(4-isopropyl-phenyl)-pyrazoline, 1-(4-isopropyl-phenyl)-3-(4-methoxystyrene)-5-(4-methoxyphenyl)-pyrazoline, 1-phenyl-3-(3,5-dimethoxystyrene)-5-(3,5-dimethoxyphenyl)-pyrazoline, 1-Phenylacetylene-3-(3,4-dimethoxystyrene)-5-(3,4-dimethoxyphenyl)-pyrazoline, 1-Phenylacetylene-3-(2,6-dimethoxystyrene)-5-(2,6-dimethoxyphenyl)-pyrazoline, 1-Phenylacetylene-3-(2,5-dimethoxystyrene)-5-(2,5-dimethoxyphenyl)-pyrazoline, 1-Phenylacetylene-3-(2,3-dimethoxystyrene)-5-(2,3-dimethoxyphenyl)-pyrazoline, 1-Phenylacetylene-3-(2,4-dimethoxystyrene)-5-(2,4-dimethoxyphenyl)-pyrazoline, 1-( 4-Methoxyphenyl)-3-(3,4-dimethoxystyrene)-5-(3,4-dimethoxyphenyl)-pyrazoline, 1-(4-methoxyphenyl)-3-(2,6-dimethoxystyrene)-5-(2,6-dimethoxyphenyl)-pyrazoline, 1-(4-methoxyphenyl)-3-(2,5-dimethoxystyrene)-5-(2,5-dimethoxyphenyl)-pyrazoline, 1-(4-methoxyphenyl)-3-(2,3-dimethoxystyrene)-5-(2,3-dimethoxyphenyl)-pyrazoline, 1-(4-methoxyphenyl)-3-(2,4-dimethoxystyrene)-5-(2,4-dimethoxyphenyl)-pyrazoline, 1-(4-tert-butyl-phenyl)-3-(3,5-(3,5-dimethoxyphenyl)-pyrazoline, 1 -(4-tert-butyl-phenyl)-3-(3,4-dimethoxystyrenyl)-5-(3,4-dimethoxyphenyl)- pyrazoline, 1 -(4-tert-butyl-phenyl)-3-(2,6-dimethoxystyrenyl)-5-(2,6-dimethoxyphenyl)- pyrazoline, 1 -(4-tert-butyl-phenyl)-3-(2,5-dimethoxystyrenyl)-5-(2,5-dimethoxyphenyl)- pyrazoline, 1 -(4-tert-butyl-phenyl)-3-(2,3-dimethoxystyrenyl)-5-(2,3-dimethoxyphenyl)- pyrazoline, 1 -(4-tert-butyl-phenyl)-3-(2,4-dimethoxystyrenyl)-5-(2,4-dimethoxyphenyl)- pyrazoline, 1 -(4-isopropyl-phenyl)-3-(3,5-dimethoxystyrenyl)-5-(3,5-dimethoxyphenyl)- pyrazoline, 1 -(4-isopropyl-phenyl)-3-(3,4-dimethoxystyrenyl)-5-(3,4-dimethoxyphenyl)- pyrazoline, 1 -(4-isopropyl-phenyl)-3-(2,6-dimethoxystyrenyl)-5-(2,6-dimethoxyphenyl)- pyrazoline, 1 -(4-isopropyl-phenyl)-3-(2,5-dimethoxystyrenyl)-5-(2,5-dimethoxyphenyl)- pyrazoline, 1 -(4-isopropyl-phenyl)-3-(2,3-dimethoxystyrenyl)-5-(2,3-dimethoxyphenyl)- pyrazoline, and 1 -(4-isopropyl-phenyl)-3-(2,4-dimethoxystyrenyl)-5-(2,4-dimethoxyphenyl)- pyrazoline.

[0080] As the dialkylaminobenzophenone compound, for example, 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, and 4-benzoyl-4'-methyl diphenyl sulfide can be given.

[0081] From the viewpoint of further improving the adhesiveness, the content of the (D) component can be 1.60 parts by mass or less, 1.50 parts by mass or less, 1.40 parts by mass or less, or 1.35 parts by mass or less, relative to 100 parts by mass of the (C) component. From the viewpoint of balancing the development property, the adhesiveness, and the strippability, the content of the (D) component can be 0.15 to 1.60 parts by mass, 0.20 to 1.50 parts by mass, 0.25 to 1.40 parts by mass, or 0.30 to 1.35 parts by mass, relative to 100 parts by mass of the (C) component.

[0082] From the viewpoint of improving the photosensitivity and the resolution, the content of the (D) component can be 0.01 to 0.10 parts by mass, 0.01 to 0.09 parts by mass, 0.01 to 0.08 parts by mass, or 0.02 to 0.05 parts by mass, relative to 100 parts by mass of the total amount of the (A) component and the (B) component.

[0083] (E) Component: Polymerization Inhibitor

[0084] From the viewpoint of further improving the resolution by inhibiting polymerization of the unexposed portion at the time of resist pattern formation, the photosensitive resin composition can further contain a polymerization inhibitor as the (E) component. As the polymerization inhibitor, for example, 4-tert-butylpyrocatechol and 2,2,6,6-tetramethyl-4-hydroxypiperidine-1-oxyl can be given.

[0085] The content of the (E) component can be 0.001 to 0.10 parts by mass, 0.005 to 0.08 parts by mass, or 0.01 to 0.06 parts by mass, relative to 100 parts by mass of the total amount of the (A) component and the (B) component.

[0086] (Other Components)

[0087] The photosensitive resin composition can further contain one or two or more other components than the above components. As the other components, a hydrogen donor (bis[4-(dimethylamino)phenyl]methane, bis[4-(diethylamino)phenyl]methane, leuco crystal violet, N-phenylglycine, etc.), a dye (malachite green, etc.), tribromophenyl sulfone, a photochromic agent, a thermochromic inhibitor, a plasticizer (p-toluenesulfonamide, etc.), a pigment, a filler, an antifoaming agent, a flame retardant, a stabilizer, an adhesion-imparting agent, a leveling agent, a peeling promoter, an antioxidant, a perfume, an imaging agent, a thermal crosslinking agent, etc. can be given. The content of the other components can be 0.005 parts by mass or more or 0.01 parts by mass or more, and can also be 20 parts by mass or less, relative to 100 parts by mass of the total amount of the (A) component and the (B) component.

[0088] The photosensitive resin composition can contain an organic solvent in order to improve the handling properties of the photosensitive composition or adjust the viscosity and the storage stability. As the organic solvent, a generally used organic solvent can be used without particular limitation. As the organic solvent, for example, methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N,N-dimethylformamide, propylene glycol monomethyl ether, and a mixed solvent of these can be given. For example, the (A) to (D) components can be dissolved in the organic solvent, and used as a solution (hereinafter, referred to as "coating liquid") in which the solid content is about 30 to 60% by mass. In addition, the solid content refers to the remaining components from which the volatile components are removed from the solution of the photosensitive resin composition.

[0089] [Photosensitive Element]

[0090] The photosensitive element of the present embodiment has a support, a photosensitive layer formed on the support, and the photosensitive layer contains the photosensitive resin composition described above. The content of each component (components (A) to (E) and other components) in the photosensitive layer, except for the volatilized substance, can be within the numerical range of the content of each component in the photosensitive resin composition described above. In the case of using the photosensitive element related to the present embodiment, after the photosensitive layer is laminated on a substrate, exposure can be performed without peeling the support (support film).

[0091] Figure 1 is a schematic cross-sectional view of a photosensitive element related to an embodiment. As shown in Figure 1 , the photosensitive element 1 has a support 2, a photosensitive layer 3 formed on the support 2, and is composed of a protective layer 4 and other layers provided as needed, derived from the photosensitive resin composition described above.

[0092] The support 2 and the protective layer 4 can each be a polymer film having heat resistance and solvent resistance, and can be, for example, a polyester film such as a polyethylene terephthalate film, a polyolefin film such as a polyethylene film or a polypropylene film, or the like. The support 2 and the protective layer 4 can each be a film of a hydrocarbon-based polymer other than a polyolefin. The film of the hydrocarbon-based polymer containing a polyolefin can be low density, and can have a density of, for example, 1.014 g / cm 3 or less. The support 2 and the protective layer 4 can each be a stretched film obtained by stretching the low-density hydrocarbon-based polymer film. The type of the polymer film constituting the protective layer 4 can be the same as or different from the type of the polymer film constituting the support 2.

[0093] These polymer films can each be purchased as, for example, a polyethylene terephthalate film of the PS series (for example, PS-25) manufactured by TEIJIN LIMITED, a polyethylene film of NF-15 manufactured by TAMAPOLY CO., LTD., or a polypropylene film manufactured by OJI PAPER CO., LTD. (for example, ALPHAN MA-410, E-200C), SHIN-ETSU FILM CO., LTD., or the like.

[0094] Regarding the thickness of the support 2, from the viewpoint of being able to suppress damage to the support 2 when peeling the support 2 from the photosensitive layer 3, it can be 1 μm or more, 5 μm or more, or 10 μm or more, and from the viewpoint of being able to appropriately expose in the case of exposure through the support 2, it can be 100 μm or less, 50 μm or less, 30 μm or less, or 20 μm or less.

[0095] The thickness of the protective layer 4 can be 1 μm or more, 5 μm or more, or 15 μm or more from the viewpoint of suppressing breakage of the protective layer 4 when the protective layer 4 is peeled and the photosensitive layer 3 and the support 2 are laminated on a substrate, and can be 100 μm or less, 50 μm or less, or 30 μm or less from the viewpoint of improving productivity.

[0096] The photosensitive layer 3 is composed of the photosensitive resin composition described above. The thickness of the photosensitive layer 3 after drying (after volatilization of the organic solvent when the photosensitive resin composition contains the organic solvent) can be 1 μm or more, 5 μm or more, 10 μm or more, or 15 μm or more from the viewpoint of facilitating coating and improving productivity, and can be 100 μm or less, 50 μm or less, 40 μm or less, or 30 μm or less from the viewpoint of further improving adhesion and resolution.

[0097] The photosensitive element 1 can be obtained, for example, as follows. First, the photosensitive layer 3 is formed on the support 2. The photosensitive layer 3 can be formed, for example, by forming a coating layer by coating the photosensitive resin composition containing the organic solvent and drying the coating layer. Next, the protective layer 4 is formed on the side of the photosensitive layer 3 opposite the support 2.

[0098] The coating layer is formed by a known method such as roll coating, comma coating, gravure coating, air knife coating, die coating, bar coating, and the like. Drying of the coating layer is performed so that the amount of the organic solvent remaining in the photosensitive layer 3 is, for example, 2% by mass or less, and specifically, for example, at 70 to 150°C for 5 to 30 minutes or so.

[0099] The photosensitive element can further have an intermediate layer between the support 2 and the photosensitive layer 3 described above. The intermediate layer can be a layer containing a water-soluble resin. As the water-soluble resin, for example, a resin containing polyvinyl alcohol as a main component can be mentioned.

[0100] The photosensitive element can not have the protective layer in another embodiment, and can further have other layers such as a buffer layer, an adhesive layer, a light-absorbing layer, a gas-barrier layer, and the like.

[0101] The photosensitive element 1 can be, for example, in a sheet shape, or in a form of a photosensitive element roll wound in a roll core in a roll shape. In the photosensitive element roll, the photosensitive element 1 is preferably wound so that the support 2 is on the outside. The roll core is formed, for example, of polyethylene, polypropylene, polystyrene, polyvinyl chloride, acrylonitrile-butadiene-styrene copolymer, or the like. An end face spacer can be provided on the end face of the photosensitive element roll from the viewpoint of end face protection, and a moisture-proof end face spacer can be provided from the viewpoint of edge fusion resistance. The photosensitive element 1 can be wrapped, for example, with a black sheet material having small moisture permeability.

[0102] The photosensitive element 1 can be suitably used for forming a resist pattern, and is particularly suitably used for the manufacturing method of a printed wiring board described later.

[0103] [Method for forming resist pattern]

[0104] The method for forming a resist pattern of the present embodiment includes a step of forming a photosensitive layer on a substrate using the photosensitive resin composition described above or the photosensitive element described above (photosensitive layer forming step), a step of forming a photocured portion by irradiating at least a part (a prescribed part) of the photosensitive layer described above with active light (exposure step), and a step of removing at least a part of the non-photocured portion described above from the substrate described above (development step), and can be configured to include other steps as necessary. The resist pattern is also referred to as a photocured product pattern of the photosensitive resin composition, and is also referred to as a relief pattern. The method for forming a resist pattern is also referred to as a manufacturing method of a substrate with a resist pattern.

[0105] (Photosensitive layer forming step)

[0106] As a method for forming a photosensitive layer on a substrate, for example, the photosensitive resin composition described above can be coated and dried, or the photosensitive layer of the photosensitive element described above can be pressed against the substrate while being heated after the protective layer is removed from the photosensitive element. In the case of using a photosensitive element, a laminate composed of a substrate, a photosensitive layer, and a support body, which are sequentially layered, can be obtained. There is no particular limitation on the substrate described above, but a circuit-forming substrate having an insulating layer and a conductor layer formed on the insulating layer, or a die pad (lead frame substrate) such as an alloy substrate can be generally used.

[0107] Regarding the surface roughness (Ra) of the substrate, from the viewpoint of improving resolution by suppressing halation due to unevenness of the substrate, it can be 200 nm or less, 180 nm or less, or 160 nm or less, and from the viewpoint of improving adhesion of the resist pattern, it can be 10 nm or more, 30 nm or more, or 40 nm or more. From the viewpoint of maintaining a balance between resolution and adhesion, Ra can be 10 to 200 nm, 30 to 180 nm, or 40 to 160 nm.

[0108] In the case of using a photosensitive element, from the viewpoints of adhesion and followability, the photosensitive layer forming step is preferably performed under reduced pressure. Heating of the photosensitive layer and / or the substrate at the time of pressing can be performed at a temperature of 70 to 130°C. Pressing can be performed at a pressure of about 0.1 to 1.0 MPa (1 to 10 kgf / cm 2 If the photosensitive layer is heated to 70 to 130°C, it is not necessary to perform a preheating process on the substrate in advance, but in order to further improve adhesion and followability, a preheating process on the substrate can also be performed.

[0109] (exposure step)

[0110] In the exposure step, at least a part of the photosensitive layer formed on the substrate is irradiated with active light, and the part irradiated with the active light is photocured, thereby forming a latent image. At this time, when a support is present on the photosensitive layer, if the support is transmissive to the active light, the active light can be irradiated through the support, but in the case where the support is light-blocking, the support is removed and then the photosensitive layer is irradiated with the active light.

[0111] As the exposure method, a method in which the active light is irradiated in an image shape through a negative or positive mask pattern called an artwork (mask exposure method) can be given. Also, a method in which the active light is irradiated in an image shape by a projection exposure method can be given. Also, a method in which the active light is irradiated in an image shape by a direct drawing exposure method such as an LDI (Laser Direct Imaging) exposure method, a DLP (Digital Light Processing) exposure method, and the like can be given.

[0112] As the light source of the active light, a publicly known light source can be used, and for example, a carbon arc lamp, a mercury vapor arc lamp, a high-pressure mercury lamp, a xenon lamp, a gas laser such as an argon laser, a solid laser such as a YAG laser, an ultraviolet laser such as a semiconductor laser, and a light source that effectively radiates visible light can be used.

[0113] (development step)

[0114] In the development step, at least a part of the unphotocured part (part other than the photocured part) of the photosensitive layer described above is removed from the substrate, and a resist pattern is formed on the substrate. In the case where a support is present on the photosensitive layer, the support is removed, and then the removal (development) of the region other than the photocured part (also referred to as an unexposed part) is performed. As the development method, a wet development and a dry development are given, but the wet development is widely used.

[0115] In the case of the wet development, a developer corresponding to the photosensitive resin composition is used, and the development is performed by a publicly known development method. As the development method, a method using an immersion method, a spin immersion method, a spray method, a brush polishing, a brush washing, a shake immersion, and the like can be given. From the viewpoint of improving the resolution, a high-pressure spray method can also be used as the development method. The development can also be performed by combining two or more of these methods.

[0116] The composition of the developer can be appropriately selected in accordance with the composition of the photosensitive resin composition described above. As the developer, for example, an alkaline aqueous solution and an organic solvent developer can be given.

[0117] From the viewpoint of safety and stability and good workability, as a developer, an aqueous alkaline solution can also be used. As the base of the aqueous alkaline solution, a hydroxide base such as a hydroxide of lithium, sodium or potassium; a carbonate base such as a carbonate or hydrogencarbonate of lithium, sodium, potassium or ammonium; an alkali metal phosphate such as potassium phosphate or sodium phosphate; an alkali metal pyrophosphate such as sodium pyrophosphate or potassium pyrophosphate; borax, sodium metasilicate, tetramethylammonium hydroxide, ethanolamine, ethylenediamine, diethylenetriamine, 2-amino-2-hydroxymethyl-l,3-propanediol, 1,3-diaminopropanol-2, morpholine or the like can be used.

[0118] As the aqueous alkaline solution for development, a dilute solution of 0.1 to 5 mass% of sodium carbonate, a dilute solution of 0.1 to 5 mass% of potassium carbonate, a dilute solution of 0.1 to 5 mass% of sodium hydroxide, a dilute solution of 0.1 to 5 mass% of sodium tetraborate or the like can be used. The pH of the aqueous alkaline solution can be set to a range of 9 to 11, and the temperature thereof can be adjusted according to the alkali developability of the photosensitive layer. For example, a small amount of an organic solvent or the like for promoting the surfactant, defoaming agent, development can also be mixed in the aqueous alkaline solution.

[0119] As the organic solvent used in the aqueous alkaline solution, for example, acetone, ethyl acetate, an alkoxyethanol having an alkoxy group of 1 to 4 carbon atoms, ethanol, isopropanol, butanol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether and diethylene glycol monobutyl ether can be mentioned.

[0120] As the organic solvent used in the organic solvent developer, for example, 1,1,1-trichloroethane, N-methyl-2-pyrrolidone, N,N-dimethylformamide, cyclohexanone, methyl isobutyl ketone and γ-butyrolactone can be mentioned. In order to prevent fire, the organic solvent developer is prepared by adding water to these organic solvents so as to be in a range of 1 to 20 mass%.

[0121] In the resist pattern forming method in the present embodiment, a process of, after the uncured portion is removed in the development process, performing heating at around 60 to 250°C or exposure at around 0.2 to 10 J / cm2as needed, thereby further curing the resist pattern can also be included. 2

[0122] [Manufacturing method of printed wiring board] The manufacturing method of the printed wiring board of the present embodiment can be constituted by including a process of forming a conductor pattern by performing etching treatment or plating treatment on the substrate on which the resist pattern is formed by the above-described resist pattern forming method, and other processes such as a resist pattern removal process as needed.

[0123] ​In the plating treatment, the resist pattern formed on the substrate is used as a mask, and the conductor layer provided on the substrate is subjected to the plating treatment. After the plating treatment, the resist can also be removed by the removal of the resist pattern described later, and further, the conductor layer covered with the resist is etched to form a conductor pattern. As the method of the plating treatment, electrolytic plating treatment or electroless plating treatment can be used, but electroless plating treatment can also be used.

[0124] In the etching treatment, the resist pattern formed on the substrate is used as a mask, and the conductor layer provided on the substrate is etched to form a conductor pattern. The method of the etching treatment can be appropriately selected depending on the conductor layer to be removed. As the etching solution, for example, a copper chloride solution, an iron chloride solution, an alkaline etching solution, and a hydrogen peroxide-based etching solution can be mentioned.

[0125] After the etching treatment or the plating treatment, the resist pattern on the substrate can also be removed. The removal of the resist pattern can be performed by peeling with a water solution having a stronger alkalinity than the alkaline water solution used in the development process described above, for example. As the water solution having a strong alkalinity, for example, a 1 to 10 mass% sodium hydroxide water solution, a 1 to 10 mass% potassium hydroxide water solution, or the like can be used.

[0126] In the case where the resist pattern is removed after the plating treatment is performed, a conductor pattern is formed by further etching the conductor layer covered with the resist by the etching treatment, whereby a desired printed wiring board can be manufactured. The method of the etching treatment at this time can be appropriately selected depending on the conductor layer to be removed. For example, the etching solution described above can be used.

[0127] The manufacturing method of the printed wiring board according to the present embodiment can be applied not only to the manufacture of a single-layer printed wiring board but also to the manufacture of a multilayer printed wiring board, and can also be applied to the manufacture of a printed wiring board having a small-diameter through hole or the like.

[0128] Example

[0129] Hereinafter, the present application will be further specifically described by examples, but the present application is not limited to these examples.

[0130] In order to synthesize the adhesive polymer, as a polymerizable monomer, a compound having a solubility parameter (δD), a logarithmic value of an octanol / water partition coefficient (logP), and a (Tg) of a homopolymer shown in Table 1 was prepared.

[0131] [Table 1]

[0132]

[0133] ((A) Adhesive Polymer)

[0134] The solutions of the adhesive polymers (A-1) to (A-10) shown in Table 2 were prepared according to the following procedures.

[0135] (A-1)

[0136] A mixture (x) was prepared by mixing acrylic acid (AA) 90.7 g, styrene (ST) 328.2 g, and 2-hydroxypropyl methacrylate (HOP) 13.0 g, t-butyl peroxy-2-ethylhexanoate (manufactured by NOF CORPORATION, trade name "PERBUTYL O") 4.5 g as a thermal radical polymerization initiator, and propylene glycol monomethyl ether 127.4 g as a solvent. A solution (a) was prepared by dissolving 4.3 g of PERBUTYL O in 13.0 g of propylene glycol monomethyl ether.

[0137] Into a flask equipped with a stirring device, a dropping funnel, a capacitor, a thermometer, and a gas introduction tube, propylene glycol monomethyl ether 47.4 g and toluene 174.8 g were added, and under a nitrogen atmosphere, gas replacement was performed while stirring and the temperature was raised to 98°C. Next, the mixture (x) was added dropwise to the flask over 2 hours. After the addition was completed, the solution in the flask was raised to 105°C over 20 minutes while continuing to stir, and stirring was performed at 105°C for 3 hours. Next, propylene glycol monomethyl ether 94.0 g and toluene 74.2 g were added, stirring was performed, and the solution was cooled to room temperature to obtain a solution of the adhesive polymer (A-1).

[0138] (A-2) to (A-10)

[0139] A solution of the adhesive polymer (A-2) to (A-10) was obtained in the same manner as in the case of obtaining the solution of the adhesive polymer (A-1), except that the mixture (x) was prepared using the polymerizable monomers shown in Table 2 in the mass ratio shown in the table.

[0140] (Weight-average molecular weight)

[0141] A 0.2 mass% THF solution was prepared by dissolving the adhesive polymer solution in tetrahydrofuran (THF) as a sample for Mw measurement. The measurement was performed by a gel permeation chromatography (GPC) method, and the Mw was derived by using a calibration curve of a standard polystyrene for conversion. The conditions of GPC are shown below.

[0142] Measurement device: Shodex GPC-101 (manufactured by Resonac Holdings Corporation)

[0143] Detector: differential refractometer Shodex RI-71S (manufactured by Resonac Holdings Corporation)

[0144] Column: Shodex LF-804 + LF-804 (manufactured by Resonac Holdings Corporation)

[0145] Column temperature: 40°C

[0146] Eluent: tetrahydrofuran (THF)

[0147] Flow rate: 1 mL / min

[0148] (Acid value)

[0149] The acid value of the binder polymer was determined by neutralization titration according to JIS K6901:2008 5.3.2.

[0150] (Glass transition temperature)

[0151] The glass transition temperature (Tg) of the binder polymer was calculated according to the Fox equation.

[0152] [Table 2]

[0153]

[0154] [Photosensitive resin composition]

[0155] A photosensitive resin composition of the examples and comparative examples was prepared by mixing each component shown in Table 3 (mass parts) with respect to the amount of the solid component of the binder polymer solution being 57 mass parts. The details of each component shown in Table 3 are as follows.

[0156] ((B) Photopolymerizable compound)

[0157] FA-321M: 2,2-bis(4-(methacryloyloxy pentaethoxy)phenyl)propane (manufactured by Resonac Holdings Corporation, number of EO groups: 10 (average))

[0158] FA-024M: PO / EO / PO-modified dimethacrylate (manufactured by Resonak Corporation, number of EO groups: 6 (average), number of PO groups: 12 (average))

[0159] BP-2EM: ethoxylated bisphenol A dimethacrylate (manufactured by Kyoeisha Chemical Co., Ltd., number of EO groups: 2.6 (average))

[0160] ((C) Photopolymerization initiator)

[0161] B-CIM: 2,2'-Bis(2-chlorophenyl)-4,4',5,5'-tetraphenylbiimidazole (manufactured by Hodogaya Chemical Co., Ltd.)

[0162] ((D) Sensitizer)

[0163] PZ-501D: 1-phenyl-3-(4-methoxystyryl)-5-(4-methoxyphenyl)pyrazoline (manufactured by NIPPON CHEMICAL WORKS CO., LTD.)

[0164] ((E) Polymerization inhibitor)

[0165] Q-TBC-5P: 4-tert-butylcatechol (manufactured by DIC Corporation)

[0166] LA-7RD: 2,2,6,6-tetramethyl-4-hydroxypiperidine-1-oxyl (manufactured by ADEKA CORPORATION)

[0167] (Other components)

[0168] (Adhesion-imparting agent)

[0169] SF-808H: mixture of carboxybenzotriazole, 5-amino-1H-tetrazole, and methoxypropanol (manufactured by SANWA KAGAKU CORP.)

[0170] (Photochromic agent)

[0171] LCV: leuco crystal violet (manufactured by YAMADA CHEMICAL CO., LTD.)

[0172] (Dye)

[0173] AKG: malachite green (manufactured by OSAKA ORGANIC CHEMICAL INDUSTRY LTD.)

[0174] [Table 3]

[0175]

[0176] [Photosensitive element]

[0177] As a support, a polyethylene terephthalate film (TORAY INDUSTRIES, INC. manufactured, trade name "FS-31") having a thickness of 16 μm was prepared. After the photosensitive resin composition was applied to the support, drying was performed in a hot air convection type drier at 90°C for 10 minutes, and a photosensitive layer having a dried thickness of 25 μm was formed. Subsequently, a polyethylene film (TAMA POLY CO., LTD. manufactured, trade name "NF-15A") was layered as a protective layer on the photosensitive layer, and a photosensitive element in which the support, the photosensitive layer, and the protective layer were layered in this order was obtained.

[0178] [Layered body]

[0179] A substrate (Ra: 150 nm) on which electrolytic-less copper plating was performed on Ajinomoto Build-up Film (registered trademark) ABF (AJINOMOTO FINE-TECHNO CO., INC., trade name "GL-102") was warmed to 80°C, and a photosensitive element was laminated (layered) on the copper surface of the substrate. The protective layer was peeled off and the photosensitive layer of the photosensitive element was brought into contact with the copper surface of the copper substrate, and lamination was performed using a heating roll at 110°C at a pressure bonding pressure of 0.4 MPa and a roll speed of 1.0 m / min. Thus, a layered body in which a substrate, a photosensitive layer, and a support were layered in this order was obtained.

[0180] [Assessment]

[0181] The layered body obtained was used as a test piece for the assessment shown below. The assessment results are shown in Table 4.

[0182] (Shortest developing time)

[0183] The support was peeled off from the test piece to expose the photosensitive layer, and a 1 mass% sodium carbonate aqueous solution at 30°C was sprayed. The time until the photosensitive layer was completely removed was measured, and this was taken as the shortest developing time.

[0184] (Adhesion)

[0185] On the support of the test piece, a glass chromium type photolithographic plate (adhesion negative: a wiring pattern having a line width / blank width of x / 3x (x: 1 to 18, unit: μm)) was used as an assessment negative, and the photosensitive layer was exposed using a projection exposure device (Ushio Inc. manufactured, trade name "UX-2240-SM-XJ01") using an ultrahigh pressure mercury lamp (365 nm) as a light source at a prescribed energy. After exposure, the support was peeled off to expose the photosensitive layer, and a 1 mass% sodium carbonate aqueous solution at 30°C was sprayed for a time twice the shortest developing time, and the unexposed portion was removed (developing treatment).

[0186] After the development treatment, in the resist pattern in which the blank portion (non-exposed portion) was completely removed and the line portion (exposed portion) was not generated with wrinkles, meandering, and defects, in the evaluation pattern in which the total of the line width and the blank width was 16 μm, the minimum line width that could form a pattern was recorded as the adhesion. The smaller the value, the better the adhesion.

[0187] (peeling time)

[0188] On the support of the test piece, a glass chromium type photomask (photomask having a planar pattern of 50 mm x 40 mm) was used as a negative film for peeling test evaluation, and a projection exposure device (manufactured by Ushio Inc., trade name "UX-2240-SM-XJ01") using an ultrahigh pressure mercury lamp (365 nm) as a light source was used to expose the photosensitive layer to the above-mentioned prescribed energy. After exposure, the support was peeled off to expose the photosensitive layer, and a 1 mass% sodium carbonate aqueous solution at 30°C was sprayed for a time twice the minimum development time to remove the non-exposed portion.

[0189] After the development treatment, it was immersed in an amine type peeling solution (15% by volume R-100S + 8% by volume R-101 aqueous solution, manufactured by MITSUBISHI GAS CHEMICAL COMPANY, INC.) heated to 50°C. The time until the photosensitive layer was completely removed was measured and was taken as the peeling time.

[0190] [Table 4]

[0191] (A) ingredients developability (sec) adhesion (μm) peeling property (sec) Example 1 A-1 23 4.7 21 Example 2 A-2 26 4.7 20 Example 3 A-3 19 5.0 19 Example 4 A-4 23 5.0 23 Example 5 A-5 30 4.7 21 Example 6 A-6 19 5.0 20 Example 7 A-7 20 5.5 20 Comparative Example 1 A-8 21 6.0 18 Comparative Example 2 A-9 28 5.5 28 Comparative Example 3 A-10 100 6.2 30

[0192] Explanation of symbols

[0193] 1 - photosensitive element, 2 - support, 3 - photosensitive layer, 4 - protective layer.

Claims

1. A photosensitive resin composition comprising a binder polymer, a photopolymerizable compound, a photopolymerization initiator, and a sensitizer, wherein the binder polymer has a first structural unit derived from acrylic acid, a second structural unit derived from styrene or a styrene derivative, and a third structural unit derived from a (meth)acrylate compound, the content of the first structural unit is 9 mass% or more and 25 mass% or less, the content of the second structural unit is 61 mass% or more, and the content of the third structural unit is 1 mass% or more and 20 mass% or less, based on the total mass of the structural units derived from the polymerizable monomers constituting the binder polymer.

2. The photosensitive resin composition according to claim 1, wherein the (meth)acrylate compound has a solubility parameter of 15.7 to 18.

7.

3. The photosensitive resin composition according to claim 1, wherein the binder polymer has an acid value of 146 to 180 mgKOH / g.

4. The photosensitive resin composition according to claim 1, wherein the binder polymer has a glass transition temperature of 90 to 120°C.

5. The photosensitive resin composition according to claim 1, wherein the binder polymer has a weight average molecular weight of 25,000 to 55,000.

6. A photosensitive element comprising a support and a photosensitive layer formed on the support using the photosensitive resin composition according to any one of claims 1 to 5.

7. A method for forming a resist pattern, comprising: a step of forming a photosensitive layer on a substrate using the photosensitive element according to claim 6; a step of forming a photocured portion by irradiating active light to at least a part of the photosensitive layer; and a step of forming a resist pattern by removing a non-photocured portion of the photosensitive layer from the substrate.

8. A method for manufacturing a printed wiring board, comprising a step of forming a conductor pattern by performing etching treatment or plating treatment on a substrate on which a resist pattern is formed by the method for forming a resist pattern according to claim 7.

9. The method for manufacturing a printed wiring board according to claim 8, further comprising a step of removing the resist pattern after the etching treatment or plating treatment. ​ ​ ​ ​ ​ ​ ​ ​ ​

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