Photosensitive element, method for forming resist pattern, and method for manufacturing printed wiring board

Abstract

The invention relates to a photosensitive element, a method for forming a resist pattern, and a method for manufacturing a printed wiring board. A photosensitive element according to the present invention is provided with: a support film; and a photosensitive layer formed on a first surface of the support film, the surface resistivity of the first surface of the support film being 1 * 1013 to 1 * 1017 Omega, and the surface resistivity of a second surface opposite to the first surface being 1 * 108 to 1 * 1012 Omega.

Description

[0001] This application is a divisional application of Chinese Application No. 202080090256.X, filed on January 28, 2020, entitled “Photosensitive Element, Method for Forming Resist Pattern, and Method for Manufacturing Printed Wiring Board”. TECHNICAL FIELD

[0002] The present application relates to a photosensitive element, a method for forming a resist pattern, and a method for manufacturing a printed wiring board. BACKGROUND

[0003] In the field of manufacturing a printed wiring board, as a resist material for etching treatment or plating treatment, a photosensitive element having a layer (hereinafter, also referred to as “photosensitive layer”) formed on a support film using a photosensitive resin composition is widely used.

[0004] A printed wiring board is manufactured using a photosensitive element, for example, by the following steps. That is, first, a photosensitive layer of a photosensitive element is laminated on a circuit-forming substrate such as a copper-clad laminate. Next, the photosensitive layer is exposed through a mask film or the like to form a photocured portion. At this time, the support film is peeled off before or after exposure. Then, a region other than the photocured portion of the photosensitive layer is removed with a developer to form a resist pattern. 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).

[0005] As a support film for a photosensitive element, a support film in which a haze value is specified, a support film in which a lubricant particle size is limited, and the like are sometimes used (for example, refer to Patent Documents 1 and 2).

[0006] Prior Art Documents Patent Documents Patent Document 1: Japanese Patent Application Publication No. 2001-13681 Patent Document 2: Japanese Patent Application Publication No. 2014-74764 SUMMARY

[0007] Technical Problem to be Solved by the Invention With recent high resolution of circuit formation, the resolution required for a photosensitive element and an exposure device used therefor is higher, and an increase in resist defects such as resist cracking and the like derived from a lubricant of a support film of the photosensitive element or a condensate thereof becomes a problem. Also, if foreign matter in the air or the like is attached to a surface of the support film on which the photosensitive layer is not formed, resist defects are likely to occur due to the foreign matter attached to the support film when exposure of the photosensitive layer is performed without peeling off the support film.

[0008] The purpose of this invention is to provide a photosensitive element that can reduce the occurrence of resist defects, a method for forming a resist pattern using the photosensitive element, and a method for manufacturing a printed circuit board.

[0009] means for solving technical problems The photosensitive element of the present invention comprises: a support film; and a photosensitive layer formed on a first surface of the support film, wherein the surface resistivity of the first surface of the support film is 1×10⁻⁶. 13 ~1×10 17 Ω, the surface resistivity of the second surface, which is opposite to the first surface, is 1×10 Ω. 8 ~1×10 12 Ω.

[0010] The method for forming a resist pattern according to the present invention includes: a lamination process in which the above-mentioned photosensitive element is laminated on a substrate in the order of photosensitive layer and support film; an exposure process in which active light is irradiated onto a predetermined portion of the photosensitive layer through the support film to form a photocurable portion; and a development process in which the area of ​​the photosensitive layer other than the photocurable portion is removed.

[0011] The method for manufacturing a printed circuit board according to the present invention includes a step of etching or plating a substrate having a resist pattern formed by the above-described resist pattern forming method to form a conductor pattern.

[0012] Invention Effects According to the present invention, a photosensitive element capable of reducing the number of resist defects, a method for forming a resist pattern using the photosensitive element, and a method for manufacturing a printed circuit board can be provided. Attached Figure Description

[0013] Figure 1 This is a schematic cross-sectional view showing one embodiment of the photosensitive element.

[0014] Figure 2 This is a schematic cross-sectional view showing one embodiment of a three-layer support membrane structure.

[0015] Figure 3 This is a schematic cross-sectional view showing one embodiment of a two-layer support membrane structure. Detailed Implementation

[0016] The present invention will now be described in detail. In this specification, the numerical range indicated by "~" represents the range encompassed by the values ​​before and after "~" as the minimum and maximum values, respectively. In the numerical ranges described in stages in this specification, the upper or lower limit of a numerical range for a certain stage can be replaced by the upper or lower limit of a numerical range for other stages. The upper or lower limit of the numerical range described in this specification can also be replaced by the values ​​shown in the embodiments.

[0017] In this specification, "(meth)acrylic acid" means at least one of "acrylic acid" and its corresponding "methacrylic acid", and the same applies to other similar terms such as (meth)acrylate.

[0018] In this specification, "solid components" refers to the non-volatile components contained in the photosensitive resin composition, excluding volatile substances such as water and solvents. It also refers to the components that remain after the resin composition has been dried and have not volatilized. In addition, it includes components that are liquid, syrupy, or waxy at room temperature around 25°C.

[0019] [Photosensitive element] The photosensitive element of this embodiment includes a support film and a photosensitive layer formed on a first surface of the support film. Figure 1 This is a schematic cross-sectional view illustrating one embodiment of a photosensitive element. For example... Figure 1 As shown, the photosensitive element 1 of this embodiment includes a support film 10 and a photosensitive layer 20.

[0020] (Supporting membrane) A photosensitive layer 20 is provided on a first surface 10a of the support film 10. The support film 10 has a second surface 10b on the side opposite to the first surface 10a. The surface resistivity of the first surface 10a in the support film is greater than the surface resistivity of the second surface 10b.

[0021] From the perspective of reducing resist defects, the surface resistivity of the first surface is 1×10⁻⁶. 13 ~1×10 17 Ω, the surface resistivity of the second surface is 1×10 8 ~1×10 12 Ω. The surface resistivity of the first surface can also be 1×10⁻⁶. 14 ~1×10 16 Ω. The surface resistivity of the second surface can also be 1×10⁻⁶. 9 ~1×10 11 .

[0022] From the viewpoint of further reducing resist defects, the support film according to this embodiment may have a first layer containing a lubricant on the first side and a second layer containing an anti-static agent and a lubricant on the second side. The support film may be a two-layer structure having a first layer and a second layer, or a three-layer structure having a substrate layer between the first layer and the second layer.

[0023] Figure 2 This is a schematic cross-sectional view showing one embodiment of a three-layer support film. The support film 10 has a first layer 12, a substrate layer 16, and a second layer 14. The first layer 12 is located on the first surface 10a side of the support film on which the photosensitive layer 20 is disposed. The second layer 14 is disposed on the side of the substrate layer 16 opposite to the first layer 12, located on the second surface 10b side of the support film 10. The support film can be a three-layer biaxially oriented polyester film.

[0024] The first layer 12 is a layer containing lubricant. The thickness of the first layer 12 can be 0.05–3.0 μm, 0.1–2.0 μm, or 0.2–1.0 μm.

[0025] The second layer 14 is a layer containing an anti-static agent and a lubricant. The thickness of the second layer 14 can be 0.05–3.0 μm, 0.1–2.0 μm, or 0.2–1.0 μm. The anti-static agent can be unevenly dispersed in the second layer 14 and can be present on the side of the second layer 14 that does not contact the substrate layer 16 (the second surface 10b side).

[0026] The substrate layer 16 is a layer that does not contain lubricants or antistatic agents. The substrate layer may, for example, be composed of a polyester film containing polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), or polyethylene 2,6-naphthalenedicarboxylate (PEN). The thickness of the substrate layer 16 may be 5–40 μm, 8–30 μm, or 10–25 μm.

[0027] A three-layer support film can be fabricated by forming the first and second layers on a substrate layer using known methods such as roller coating, flow coating, spray coating, curtain flowcoat, dip coating, and slot coating.

[0028] Figure 3 This is a schematic cross-sectional view showing one embodiment of a two-layer support film. The support film 10 has a first layer 22 and a second layer 24. The first layer 22 is located on the first surface 10a side of the support film on which the photosensitive layer 20 is disposed. The second layer 24 is located on the second surface 10b side. The support film can be a two-layer biaxially oriented polyester film.

[0029] The first layer 22 is a layer containing lubricant. The thickness of the first layer 22 can be 6–50 μm, 8–40 μm, or 10–25 μm.

[0030] The first layer can be formed by kneading lubricant into polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene 2,6-naphthalenedicarboxylate (PEN).

[0031] The second layer 24 is a layer containing an anti-static agent and a lubricant. The thickness of the second layer 24 can be 0.05–3.0 μm, 0.1–2.0 μm, or 0.2–1.0 μm. The anti-static agent can be unevenly dispersed in the second layer 24 and can exist on the side of the second layer 24 that is not in contact with the first layer 22 (the second surface 10b side).

[0032] For example, after the first layer 22 is formed, the second layer 24 can be formed on the first layer 22 using known methods such as roller coating, flow coating, spray coating, curtain coating, dip coating, slot coating, etc.

[0033] The average particle size of the lubricant contained in the first and second layers is preferably 1 μm or less, and can be 0.1–1 μm, 0.1–0.8 μm, or 0.2–0.5 μm. From the viewpoint of improving the smoothness of the first surface 10a of the support film, the average particle size of the lubricant contained in the first layer is preferably smaller than the average particle size of the lubricant contained in the second layer. The average particle size of the lubricant can be determined by observing the surface of the support film using a scanning electron microscope.

[0034] From the viewpoint of improving the smoothness of the first surface 10a of the support film, the number of lubricants contained in the first layer is preferably less than the number of lubricants contained in the second layer. The number of lubricants contained in the first layer is preferably 150 or less per 15 μm × 15 μm square, and can be 10 to 120 or 15 to 100. The number of lubricants contained in the second layer is preferably 500 or less per 150 μm × 150 μm square, and can be 200 to 480 or 300 to 460. The number of lubricants can be determined by observing the surface of the support film using a confocal laser microscope.

[0035] As a lubricant, it is not particularly limited as long as it does not impede the light transmittance of the supporting film and is used in the production of polyester films; it can be an inorganic lubricant or an organic lubricant. Examples of inorganic lubricants include salts of silica, calcium carbonate, alumina, wollastonite, kaolin, zinc oxide, barium sulfate, calcium phosphate, calcium, barium, zinc, or manganese with terephthalic acid. Examples of organic lubricants include cross-linked polymers such as polystyrene and polymethyl methacrylate.

[0036] The antistatic agent can be selected within a range that does not impede the light transmittance of the support film. Examples of antistatic agents include compounds containing hydroxyl groups such as polyoxyalkylene glycol, π-conjugated polymers such as alkoxy polythiophene, ester products of polyols with three or more hydroxyl groups and aliphatic monocarboxylic acids with 12 or more carbon atoms such as glyceryl tristearate, compounds containing lithium metal such as lithium dodecylbenzenesulfonate, organic sulfonate metal salts such as sodium dodecylbenzenesulfonate, and compounds containing lithium metal such as lithium trifluoromethanesulfonate.

[0037] The haze of the supporting membrane can be 0.01–5.0%, 0.01–1.5%, 0.01–1.0%, or 0.01–0.5%. Haze refers to the value measured using a commercially available turbidimeter according to the method specified in JIS K7105. Haze can be measured, for example, using a commercially available turbidimeter such as the NDH-5000 (manufactured by NIPPON DENSHOKU INDUSTRIES Co.,LTD., trade name).

[0038] The thickness of the support membrane can be 5–50 μm, 8–40 μm, 10–30 μm, or 10–25 μm.

[0039] (Photosensitive layer) The photosensitive layer 20 is a layer formed from a photosensitive resin composition. The photosensitive resin composition used to form the photosensitive layer 20 is not particularly limited. The photosensitive resin composition may contain (A) an adhesive polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator.

[0040] (A) The adhesive polymer (hereinafter also referred to as "(A) component") can be manufactured, for example, by free radical polymerization of the polymerizable monomer. Examples of polymerizable monomers include styrene or styrene derivatives, acrylamides such as diacetone acrylamide, acrylonitrile, ethers of vinyl alcohols such as vinyl-n-butyl ether, alkyl methacrylates, benzyl methacrylate, tetrahydrofurfuryl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, glycidyl methacrylate, 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3-tetrafluoropropyl (meth)acrylate, (meth)acrylic acid, α-bromoacrylic acid, α-chloroacrylic acid, β-furanyl (meth)acrylic acid, β-styryl (meth)acrylic acid, maleic acid, maleic anhydride, monomethyl maleate, monoethyl maleate, monoisopropyl maleate, fumaric acid, cinnamic acid, α-cyanocinonic acid, itaconic acid, crotonic acid, and propynic acid. Polymerizable monomers can be used alone or in combination of two or more.

[0041] From the viewpoint of alkali-developable properties, component (A) can have a carboxyl group. Component (A) having a carboxyl group can be manufactured, for example, by free radical polymerization of a polymerizable monomer having a carboxyl group with other polymerizable monomers. The polymerizable monomer having a carboxyl group can be (meth)acrylic acid or methacrylic acid.

[0042] From the perspective of achieving a good balance between improving alkali developability and alkali resistance, based on the total amount of component (A), the content of structural units of polymerizable monomers with carboxyl groups can be 10–50% by mass, 15–40% by mass, or 20–35% by mass. When the carboxyl group content is 10% by mass or more, there is a tendency to improve alkali developability, and when it is 50% by mass or less, there is a tendency to have excellent alkali resistance.

[0043] The acid value of component (A) with a carboxyl group can be 50–250 mg KOH / g, 50–200 mg KOH / g, or 100–200 mg KOH / g.

[0044] From the viewpoint of adhesion and peeling properties, component (A) may have structural units based on styrene or styrene derivatives. Styrene derivatives are polymerizable compounds, such as vinyltoluene and α-methylstyrene, in which hydrogen atoms at the α-position or in the aromatic ring of styrene are substituted. The content of styrene-based or styrene derivative structural units in component (A) may be 10–60% by mass, 15–50% by mass, 35–50% by mass, or 40–50% by mass. When this content is 10% by mass or more, there is a tendency for improved adhesion; when it is 60% by mass or less, there is a tendency to suppress the enlargement of the peeling sheet during development and to suppress the prolonged peeling time.

[0045] From the viewpoint of improving resolution, component (A) may have structural units based on benzyl methacrylate. The content of structural units derived from benzyl methacrylate in component (A) may be 10–40% by mass, 15–35% by mass, or 20–30% by mass.

[0046] From the viewpoint of improving plasticity, component (A) may have structural units based on alkyl (meth)acrylates. Examples of alkyl (meth)acrylates include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, and dodecyl (meth)acrylate.

[0047] The weight-average molecular weight (Mw) of component (A) can be 10,000–300,000, 150,000–150,000, 200,000–100,000, or 25,000–80,000. When the Mw of component (A) is above 10,000, it tends to have excellent resistance to developer; when it is below 300,000, it tends to inhibit the prolongation of development time. The dispersibility (weight-average molecular weight / number-average molecular weight) of component (A) can be 1.0–3.0 or 1.0–2.0. If the dispersibility decreases, the resolution tends to improve.

[0048] The weight-average molecular weight and number-average molecular weight in this specification are values ​​determined by gel permeation chromatography (GPC) and converted using standard polystyrene as the standard sample.

[0049] (A) Component can be used alone or in combination of two or more. Examples of (A) components used in combination of two or more include two or more adhesive polymers formed from monomers with different polymerizability, two or more adhesive polymers with different molecular weights (Mw), and two or more adhesive polymers with different dispersions.

[0050] The content of component (A) can be 30-80 parts by mass, 40-75 parts by mass, 50-70 parts by mass, or 50-60 parts by mass relative to the total amount of component (A) and component (B) described later (100 parts by mass). If the content of component (A) is within this range, the strength of the photocured portion of the photosensitive layer becomes better.

[0051] As a (B) photopolymerizable compound (hereinafter also referred to as "(B) component"), a compound having at least one olefinic unsaturated bond within the molecule may be used. (B) component may be used alone or in combination of two or more.

[0052] (B) The olefinic unsaturated bonds in the component are not particularly limited as long as they can undergo photopolymerization. Examples of olefinic unsaturated bonds include α,β-unsaturated carbonyl groups such as (meth)acryloyl groups. Examples of photopolymerizable compounds having α,β-unsaturated carbonyl groups include α,β-unsaturated carboxylic acid esters of polyols, bisphenol-type (meth)acrylates, α,β-unsaturated carboxylic acid adducts of compounds containing glycidyl groups, (meth)acrylates having urethane bonds, nonylphenoxy polyethyloxyacrylates, (meth)acrylates having a phthalic acid backbone, and (meth)acrylate alkyl esters.

[0053] Examples of α,β-unsaturated carboxylic acid esters that are polyols include polyethylene glycol di(meth)acrylate with 2 to 14 ethylenes, polypropylene glycol di(meth)acrylate with 2 to 14 propylene groups, polyethylene-polypropylene glycol di(meth)acrylate with 2 to 14 ethylenes and 2 to 14 propylene groups, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, EO-modified trimethylolpropane tri(meth)acrylate, PO-modified trimethylolpropane tri(meth)acrylate, EO and PO-modified trimethylolpropane tri(meth)acrylate, tetramethylolmethane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, and (meth)acrylate compounds having a backbone derived from dipentaerythritol or pentaerythritol. "EO modification" refers to substances with a block structure containing ethylene oxide (EO) groups, while "PO modification" refers to substances with a block structure containing propylene oxide (PO) groups.

[0054] From the viewpoint of improving the flexibility of the resist pattern, component (B) may contain polyalkylene glycol di(meth)acrylate. Polyalkylene glycol di(meth)acrylate may have at least one of EO and PO groups, or both EO and PO groups. In polyalkylene glycol di(meth)acrylate containing both EO and PO groups, the EO and PO groups may exist in continuous block formation or randomly. Furthermore, the PO group may be either oxopropylene or oxoisopropylene. Additionally, in the (poly)oxoisopropylene group, the secondary carbon of the propylene group may be bonded to an oxygen atom, or the primary carbon may be bonded to an oxygen atom.

[0055] Commercially available polyalkylene glycol di(meth)acrylates include, for example, FA-023M (manufactured by Hitachi Chemical Co., Ltd.), FA-024M (manufactured by Hitachi Chemical Co., Ltd.), and NK Ester HEMA-9P (manufactured by Shin-Nakamura Chemical Co., Ltd.).

[0056] From the viewpoint of improving the flexibility of the resist pattern, component (B) may contain (meth)acrylates having urethane bonds. Examples of (meth)acrylates having urethane bonds include addition products of (meth)acrylate monomers having an OH group at the β-position and diisocyanates (isoflurone diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate, 1,6-hexamethylene diisocyanate, etc.), tris((meth)acryloyloxytetraethylene glycol isocyanate)hexamethylene isocyanurate, EO-modified urethane di(meth)acrylates, and EO, PO-modified urethane di(meth)acrylates.

[0057] Commercially available EO-modified urethane di(meth)acrylates include, for example, "UA-11" and "UA-21EB" (manufactured by Shin-Nakamura Chemical Co., Ltd.). Commercially available EO and PO-modified urethane di(meth)acrylates include, for example, "UA-13" (manufactured by Shin-Nakamura Chemical Co., Ltd.).

[0058] From the viewpoint of easily forming a thick-film resist pattern and achieving a good balance between resolution and adhesion, component (B) may contain a (meth)acrylate compound having a backbone derived from dipentaerythritol or pentaerythritol. The (meth)acrylate compound having a backbone derived from dipentaerythritol or pentaerythritol preferably has four or more (meth)acryloyl groups and may be dipentaerythritol penta(meth)acrylate or dipentaerythritol hexa(meth)acrylate.

[0059] As component (B), it may contain a polyfunctional (meth)acrylate compound obtained by reacting an α,β-unsaturated carboxylic acid with a polyol. The polyfunctional (meth)acrylate compound may have at least one of an EO group and a PO group, or both an EO group and a PO group. As such a compound, dipentaerythritol (meth)acrylate having an EO group can be used. Commercially available examples of dipentaerythritol (meth)acrylate having an EO group include DPEA-12 (manufactured by Nippon Kayaku Co., Ltd.).

[0060] From the viewpoint of improving resolution and peeling properties after curing, component (B) may contain bisphenol-type (meth)acrylates, or it may contain bisphenol A-type (meth)acrylates. Examples of bisphenol A-type (meth)acrylates include 2,2-bis(4-((meth)acryloyloxypolyethoxy)phenyl)propane, 2,2-bis(4-((meth)acryloyloxypolypropoxy)phenyl)propane, 2,2-bis(4-((meth)acryloyloxypolybutoxy)phenyl)propane, and 2,2-bis(4-((meth)acryloyloxypolyethoxypolypropoxy)phenyl)propane.

[0061] Examples of commercially available products include 2,2-bis(4-((meth)acryloyloxydiethoxy)phenyl)propane such as BPE-200 (Shin-Nakamura Chemical Co., Ltd.), and 2,2-bis(4-(methacryloyloxypentethoxy)phenyl)propane such as BPE-500 (Shin-Nakamura Chemical Co., Ltd.) and FA-321M (Hitachi Chemical Co., Ltd.).

[0062] Examples of nonylphenoxy polyethylene acrylates include nonylphenoxy tetraethylene acrylate, nonylphenoxy pentaethylene acrylate, nonylphenoxy hexadecimal acrylate, nonylphenoxy heptaethylene acrylate, nonylphenoxy octaethylene acrylate, nonylphenoxy nonaethylene acrylate, nonylphenoxy decaethylene acrylate, and nonylphenoxy undecaethylene acrylate.

[0063] Examples of (meth)acrylates having a phthalic acid backbone include γ-chloro-β-hydroxypropyl-β'-(meth)acryloyloxyethyl-phthalate, β-hydroxyethyl-β'-(meth)acryloyloxyethyl-phthalate, and β-hydroxypropyl-β'-(meth)acryloyloxyethyl-phthalate. γ-chloro-β-hydroxypropyl-β'-methacryloyloxyethyl-phthalate is commercially available as FA-MECH (Hitachi Chemical Co., Ltd.).

[0064] As the photopolymerization initiator (C) (hereinafter also referred to as "component (C)"), there are no particular restrictions as long as it enables component (B) to polymerize, and it can be appropriately selected from commonly used photopolymerization initiators. Component (C) can be used alone or in combination of two or more.

[0065] Examples of photoinitiators that can be included as component (C) include acylphosphine oxides, oxime esters, aromatic ketones, quinones, alkylbenzene ketones, imidazoles, acridines, phenylglycines, and coumarins. From the viewpoint of achieving a good balance between improving sensitivity and resolution, component (C) may include acridine photoinitiators, phenylglycine photoinitiators, or imidazole photoinitiators.

[0066] Examples of acridine-based photopolymerization initiators include 9-phenylacridine, 9-(p-methylphenyl)acridine, 9-(m-methylphenyl)acridine, 9-(p-chlorophenyl)acridine, 9-(m-chlorophenyl)acridine, 9-aminoacridine, 9-dimethylaminoacridine, 9-diethylaminoacridine, 9-pentylaminoacridine, 1,2-bis(9-acridyl)ethane, 1,4-bis(9-acridyl)butane, 1,6-bis(9-acridyl)hexane, 1,8-bis(9-acridyl)octane, and 1, 10-bis(9-acridyl)decane, 1,12-bis(9-acridyl)dodecane, 1,14-bis(9-acridyl)tetradecane, 1,16-bis(9-acridyl)hexadecane, 1,18-bis(9-acridyl)octadecane, 1,20-bis(9-acridyl)eicosane and other bis(9-acridyl)alkanes, 1,3-bis(9-acridyl)-2-oxapropane, 1,3-bis(9-acridyl)-2-thiopropane and 1,5-bis(9-acridyl)-3-thiopentane.

[0067] Examples of phenylglycine photopolymerization initiators include N-phenylglycine, N-methyl-N-phenylglycine, and N-ethyl-N-phenylglycine.

[0068] Examples of hexaaryl biimidazole photopolymerization initiators 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)-biimidazole. 2,2'-bis-(2-fluorophenyl)-4,4',5,5'-tetra-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,3-difluoromethylphenyl)-4,4',5,5'-tetra-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,4-difluorophenyl)-4,4',5,5'-tetra-(3-methoxyphenyl)-biimidazole and 2,2'-bis-(2,5-difluorophenyl)-4,4',5,5'-tetra-(3-methoxyphenyl)-biimidazole.

[0069] Compared to the total amount of components (A) and (B) 100 parts by mass, the content of component (C) can be 0.1–10 parts by mass, 1–5 parts by mass, or 2–4.5 parts by mass. When the content of component (C) is 0.1 parts by mass or more, it tends to improve photosensitivity, resolution, and adhesion; when it is 10 parts by mass or less, it tends to have better resist patterning properties.

[0070] The photosensitive resin composition according to this embodiment may also contain a (D) photosensitizer (hereinafter also referred to as "(D) component"). By containing the (D) component, the absorption wavelength of the active light used in the exposure can be effectively utilized. The (D) component may be used alone or in combination of two or more.

[0071] Examples of components (D) include dialkylaminobenzophenone compounds, pyrazoline compounds, anthracene compounds, coumarin compounds, xanthonesone compounds, thioxanthonesone compounds, oxazole compounds, benzoxazole compounds, thiazole compounds, benzothiazole compounds, triazole compounds, stilbene compounds, triazine compounds, thiophene compounds, naphthalenedicarboximide compounds, triarylamine compounds, and aminoacridine compounds. From the viewpoint of further improving resolution, component (D) may include pyrazoline compounds or anthracene compounds.

[0072] Examples of pyrazoline compounds include 1-(4-methoxyphenyl)-3-styryl-5-phenyl-pyrazoline, 1-phenyl-3-(4-methoxystyryl)-5-(4-methoxyphenyl)-pyrazoline, 1,5-bis-(4-methoxyphenyl)-3-(4-methoxystyryl)-pyrazoline, 1-(4-isopropylphenyl)-3-styryl-5-phenyl-pyrazoline, 1-phenyl-3-(4-isopropylstyryl)-5-(4-isopropylphenyl)-pyrazoline, 1,5-bis-(4-isopropylphenyl)-3-(4-isopropylstyryl)-pyrazoline, and 1-(4-methoxyphenyl)-3-(4-tert-butylstyryl)-5-(4-tert-butylstyryl)-pyrazoline. 1-(4-tert-butyl-phenyl)-3-(4-methoxystyryl)-5-(4-methoxyphenyl)-pyrazoline, 1-(4-isopropyl-phenyl)-3-(4-tert-butyl-styryl)-5-(4-tert-butyl-phenyl)-pyrazoline, 1-(4-tert-butyl-phenyl)-3-(4-isopropyl-styryl)-5-(4-isopropyl-phenyl)-pyrazoline, 1-(4-methoxyphenyl)-3-(4-isopropyl-styryl)-5-(4-isopropyl-phenyl)-pyrazoline, 1-(4-isopropyl-phenyl)-3-(4-methoxystyryl)-5-(4-methoxyphenyl)-pyrazoline, 1-phenyl-3-(3,5-dimethoxystyryl)-5- (3,5-Dimethoxyphenyl)-pyrazoline, 1-phenyl-3-(3,4-dimethoxystyryl)-5-(3,4-dimethoxyphenyl)-pyrazoline, 1-phenyl-3-(2,6-dimethoxystyryl)-5-(2,6-dimethoxyphenyl)-pyrazoline, 1-phenyl-3-(2,5-dimethoxystyryl)-5-(2,5-dimethoxyphenyl)-pyrazoline, 1-phenyl-3-(2,3-dimethoxystyryl)-5-(2,3-dimethoxyphenyl)-pyrazoline, 1-phenyl-3-(2,4-dimethoxystyryl)-5-(2,4-dimethoxyphenyl)-pyrazoline, 1-(4-methoxyphenyl)-3-(3,5-dimethoxystyryl) 1-(4-methoxyphenyl)-3-(3,4-dimethoxystyryl)-5-(3,4-dimethoxyphenyl)-pyrazoline, 1-(4-methoxyphenyl)-3-(2,6-dimethoxystyryl)-5-(2,6-dimethoxyphenyl)-pyrazoline, 1-(4-methoxyphenyl)-3-(2,5-dimethoxystyryl)-5-(2,5-dimethoxyphenyl)-pyrazoline, 1-(4-methoxyphenyl)-3-(2,3-dimethoxystyryl)-5-(2,3-dimethoxyphenyl)-pyrazoline, 1-(4-methoxyphenyl)-3-(2,4-dimethoxystyryl)-5-(2,6 ...4-Dimethoxyphenyl)-pyrazoline, 1-(4-tert-butyl-phenyl)-3-(3,5-dimethoxystyryl)-5-(3,5-dimethoxyphenyl)-pyrazoline, 1-(4-tert-butyl-phenyl)-3-(3,4-dimethoxystyryl)-5-(3,4-dimethoxyphenyl)-pyrazoline, 1-(4-tert-butyl-phenyl)-3-(2,6-dimethoxystyryl)-5-(2,6-dimethoxyphenyl)-pyrazoline 1-(4-tert-butyl-phenyl)-3-(2,5-dimethoxystyryl)-5-(2,5-dimethoxyphenyl)-pyrazoline, 1-(4-tert-butyl-phenyl)-3-(2,3-dimethoxystyryl)-5-(2,3-dimethoxyphenyl)-pyrazoline, 1-(4-tert-butyl-phenyl)-3-(2,4-dimethoxystyryl)-5-(2,4-dimethoxyphenyl)-pyrazoline 1-(4-isopropyl-phenyl)-3-(3,5-dimethoxystyryl)-5-(3,5-dimethoxyphenyl)-pyrazoline, 1-(4-isopropyl-phenyl)-3-(3,4-dimethoxystyryl)-5-(3,4-dimethoxyphenyl)-pyrazoline, 1-(4-isopropyl-phenyl)-3-(2,6-dimethoxystyryl)-5-(2,6-dimethoxyphenyl)- Pyrazoline, 1-(4-isopropyl-phenyl)-3-(2,5-dimethoxystyryl)-5-(2,5-dimethoxyphenyl)-pyrazoline, 1-(4-isopropyl-phenyl)-3-(2,3-dimethoxystyryl)-5-(2,3-dimethoxyphenyl)-pyrazoline, and 1-(4-isopropyl-phenyl)-3-(2,4-dimethoxystyryl)-5-(2,4-dimethoxyphenyl)-pyrazoline.

[0073] Examples of anthracene compounds include 9,10-dimethoxyanthracene, 9,10-diethoxyanthracene, 9,10-dipropoxyanthracene, 9,10-dibutoxyanthracene and 9,10-dipentoxyanthracene.

[0074] From the perspective of improving light sensitivity and resolution, relative to the total amount of components (A) and (B) 100 parts by mass, the content of component (D) can be 0.01 to 5 parts by mass, 0.01 to 1 part by mass, or 0.01 to 0.2 parts by mass.

[0075] The photosensitive resin composition involved in this embodiment may also contain, as needed, additives such as dyes, photochromic agents, heat-developing inhibitors, plasticizers, pigments, fillers, defoamers, flame retardants, adhesion promoters, leveling agents, peel accelerators, antioxidants, fragrances, developing agents, thermal crosslinking agents, and polymerization inhibitors. These additives may be used alone or in combination of two or more.

[0076] Examples of dyes include peacock green, Victoria blue, brilliant green, and methyl violet. Examples of photochromic agents include tribromophenyl sulfone, colorless crystal violet, diphenylamine, benzylamine, triphenylamine, diethylaniline, and o-chloroaniline. Examples of plasticizers include p-toluenesulfonamide.

[0077] The photosensitive resin composition can be dissolved in solvents such as methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N,N-dimethylformamide, propylene glycol monomethyl ether, or mixtures thereof to prepare a solution with a solid content of about 30-60% by mass.

[0078] The thickness of the photosensitive layer 20 can be 1–200 μm, 5–100 μm, 10–50 μm, or 10–30 μm.

[0079] (Protective film) The photosensitive element according to this embodiment may have a protective film (not shown) on the side of the photosensitive layer 20 opposite to the support film 10. As the protective film, it is preferable to use a film that makes the adhesive force between the photosensitive layer 20 and the protective film less than the adhesive force between the photosensitive layer 20 and the support film 10. As the protective film, a polyolefin film such as polyethylene or polypropylene can be used. The protective film can be a polyethylene film.

[0080] The thickness of the protective film can be 5–100 μm, 5–70 μm, 10–60 μm, 10–50 μm, 15–40 μm, or 15–30 μm.

[0081] (Intermediate layer) The photosensitive element of this embodiment may have an intermediate layer (not shown) between the support film and the photosensitive layer. The adhesive force between the support film and the intermediate layer may be less than the adhesive force between the intermediate layer and the photosensitive layer. The intermediate layer may be water-soluble or soluble in a developer. The intermediate layer is formed using a resin composition for forming an intermediate layer, described later.

[0082] The resin composition for forming the intermediate layer may contain a water-soluble resin. By containing a water-soluble resin, the solubility of the formed intermediate layer tends to be improved. Furthermore, since it is easier to maintain the layer separation between the formed intermediate layer and the photosensitive layer for a long period, the stability tends to be improved. Examples of water-soluble resins include polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP). From the viewpoint of low oxygen permeability and further suppression of free radical deactivation generated by active light used for exposure, the resin composition for forming the intermediate layer may contain PVA. PVA can be obtained, for example, by saponifying polyvinyl acetate obtained by polymerizing vinyl acetate. The degree of saponification of the PVA used in this embodiment may be 50 mol% or more, 70 mol% or more, or 80 mol% or more. By using PVA with a saponification degree of 50 mol% or more, the gas barrier properties of the intermediate layer can be further improved, and the resolution of the formed resist pattern can be further improved. In addition, "degree of saponification" in this specification refers to the value measured in accordance with JIS K 6726 (1994) (Test Method for Polyvinyl Alcohol) as specified in Japanese Industrial Standards. Furthermore, the upper limit of this degree of saponification can be 100 moles.

[0083] The average degree of polymerization of polyvinyl alcohol can be 300–3500, 300–2500, or 300–1000. Furthermore, the average degree of polymerization of polyvinylpyrrolidone can be 10000–100000 or 10000–50000. The above-mentioned polyvinyl alcohols can be combined with two or more polyvinyl alcohols having different degrees of saponification, viscosity, degree of polymerization, and modifying species.

[0084] The resin composition for forming the intermediate layer may contain a resin that is soluble in the developer. As a resin soluble in the developer, it may contain, for example, component (A) used in photosensitive resin compositions, or component (B). By containing a resin soluble in the developer, there is a tendency for improved adhesion between the formed intermediate layer and the photosensitive layer, and a tendency for the photosensitive layer to be easily formed on the formed intermediate layer.

[0085] To improve the workability of the resin composition or to adjust its viscosity and storage stability, the resin composition for forming the intermediate layer may, as needed, contain at least one solvent. Examples of solvents include water and organic solvents. Examples of organic solvents include methanol, acetone, toluene, or mixtures thereof. From the viewpoint of improving the drying efficiency during intermediate layer formation, methanol may be included. Furthermore, when the resin composition for forming the intermediate layer contains a water-soluble resin, water, and methanol, from the viewpoint of solubility of the water-soluble resin, the methanol content relative to 100 parts by mass of water may be 1-100 parts by mass, 10-80 parts by mass, or 20-60 parts by mass. The water-soluble resin content relative to 100 parts by mass of water may be 1-50 parts by mass or 10-30 parts by mass.

[0086] The resin composition for forming the intermediate layer can be incorporated with known additives such as surfactants, plasticizers, and leveling agents. Examples of leveling agents include silicone-based leveling agents. Commercially available silicone-based leveling agents include, for example, Polyflow KL-401 (manufactured by Kyoisha Chemical Co., Ltd.). When a leveling agent is included, from the viewpoint of the ease of intermediate layer formation, the content of the leveling agent can be 0.01 to 2.0 parts by weight or 0.05 to 1.0 parts by weight relative to 100 parts by weight of the resin composition for forming the intermediate layer.

[0087] As a surfactant, silicone-based or fluorinated surfactants may be included to improve the peelability with the support film. These surfactants may be used alone or in combination of two or more. When a surfactant is included, from the viewpoint of easy formation of the interlayer, the surfactant content may be 0.01–1.0 parts by mass, 0.05–0.5 parts by mass, or 0.1–0.3 parts by mass relative to 100 parts by mass of the resin composition for forming the interlayer.

[0088] Polyol compounds may be included as plasticizers, for example, from the viewpoint of improving the ease of formation of the intermediate layer. Examples of plasticizers include glycerols such as glycerol, diglycerol, and triglycerol; (poly)alkylene glycols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, and polypropylene glycol; and trimethylolpropane. These plasticizers may be used alone or in combination of two or more.

[0089] The thickness of the intermediate layer is not particularly limited, but from the viewpoint of reproducibility, it can be less than 12 μm, less than 10 μm, or less than 8 μm. Furthermore, from the viewpoint of the ease of formation and resolution of the intermediate layer, the thickness of the intermediate layer can be more than 1.0 μm, more than 1.5 μm, or more than 2 μm.

[0090] [Methods for forming resist patterns] The method for forming a resist pattern according to this embodiment includes: a lamination process in which a photosensitive layer 20 of a photosensitive element 1 is laminated onto a substrate in the order of photosensitive layer and support film; an exposure process in which active light is irradiated onto a predetermined portion of the photosensitive layer 20 through the support film 10 to form a photocurable portion; and a development process in which the areas of the photosensitive layer 20 other than the photocurable portion are removed.

[0091] In the lamination process, for example, the photosensitive layer of the photosensitive element and the support film are laminated onto the substrate in this order. In the lamination process, as a method for laminating the photosensitive layer 20 onto the substrate, when a protective film is present on the photosensitive layer 20, a method can be adopted as follows: after removing the protective film, the photosensitive layer 20 is heated to approximately 70–130°C while being pressed onto the substrate under a pressure of approximately 0.1–1 MPa. Lamination can also be performed under reduced pressure. Furthermore, the surface of the laminated photosensitive layer 20 on the substrate is usually a metallic surface, but this is not particularly limited. Moreover, to further improve lamination performance, a preheating treatment of the substrate can be performed.

[0092] Next, in the exposure process, for example, active light is irradiated onto a predetermined portion of the photosensitive layer 20 through the support film 10 to form a photocurable portion on the photosensitive layer 20. Examples of exposure methods include methods that irradiate active light in an image-like manner using a negative or positive mask pattern called an artwork (mask exposure method), methods that irradiate active light in an image-like manner using projection exposure method, methods that irradiate active light in an image-like manner using LDI (Laser Direct Imaging) exposure method, DLP (Digital Light Processing) exposure method, and other direct drawing exposure methods.

[0093] As a source of active light, known light sources can be used, such as gas lasers such as carbon arc lamps, mercury vapor arc lamps, high-pressure mercury lamps, xenon lamps, and argon lasers; solid-state lasers such as YAG lasers; and semiconductor lasers that effectively emit ultraviolet and visible light.

[0094] From the perspective of improving adhesion, post-exposure baking (PEB) can be performed after exposure and before development. The temperature during PEB can be 50–100°C. Heating devices such as heating plates, box dryers, and heating rollers can be used.

[0095] In the developing process, a resist pattern is formed on the substrate by removing at least a portion of the photosensitive layer, excluding the photocurable portion, from the substrate.

[0096] In the developing process, after the support film 10 is peeled off from the photosensitive layer 20, the areas of the photosensitive layer other than the photocured portion are removed. In the developing process, for example, wet developing or dry developing with developing solutions such as alkaline aqueous solutions, aqueous developing solutions, or organic solvents is used to remove the unexposed portions (uncured portions) of the photosensitive layer 20 and then developing is performed, thereby enabling the creation of a resist pattern.

[0097] Examples of alkaline aqueous solutions include 0.1–5% by mass sodium carbonate solution, 0.1–5% by mass potassium carbonate solution, and 0.1–5% by mass sodium hydroxide solution. The pH of the alkaline aqueous solution is preferably in the range of 9–11. The temperature of the alkaline aqueous solution is adjusted according to the developability of the photosensitive layer 20. Furthermore, the alkaline aqueous solution may contain surfactants, defoamers, organic solvents, etc. Examples of developing methods include immersion, spraying, brushing, and slapping.

[0098] As a post-development treatment, it can be performed by heating at approximately 60–250°C or at a pressure of 0.2–10 J / cm², depending on the requirements. 2 The exposure to the left and right sides further solidifies the resist pattern.

[0099] [Manufacturing methods for printed circuit boards] The method for manufacturing a printed circuit board according to this embodiment includes a step of forming a conductor pattern by etching or plating a substrate having a resist pattern formed by the above-described resist pattern forming method. Here, the etching or plating of the substrate can be performed by using the resist pattern as a mask and etching or plating the surface of the substrate using a known method.

[0100] Etching solutions used for etching include, for example, copper chloride solution, ferric chloride solution, and alkaline etching solution. Plating methods include, for example, copper plating, solder plating, nickel plating, and gold plating.

[0101] After etching or plating, the resist pattern can be removed, for example, using an aqueous solution that is more alkaline than the alkaline aqueous solution used for development. Examples of such a strongly alkaline aqueous solution include a 1-10% by mass sodium hydroxide solution and a 1-10% by mass potassium hydroxide solution. Furthermore, examples of removal methods include immersion and spraying. Additionally, the printed circuit board with the resist pattern can be a multilayer printed circuit board and can have small-diameter through-holes.

[0102] When plating a substrate having an insulating layer and a conductor layer formed on the insulating layer, it is necessary to remove the conductor layer except for the resist pattern. Examples of such removal methods include: etching gently after peeling off the resist pattern; or, after solder plating or similar processes following plating, stripping the resist pattern and masking the wiring portions with a solder mask, then using an etchant capable of etching only the conductor layer not masked by the solder mask.

[0103] The preferred embodiments of the present invention have been described above, but the present invention is not limited to any of the above embodiments.

[0104] Example The present invention will now be described in detail with reference to embodiments, but the present invention is not limited thereto.

[0105] [Photosensitive Resin Composition] A photosensitive resin composition was prepared by mixing the components shown in Table 1 in the indicated proportions (parts by mass). Details of each component in Table 1 are as follows.

[0106] (Adhesive polymer) A-1: Ethylene glycol monomethyl ether / toluene solution (solid content: 40% by mass) of a copolymer of methacrylic acid / methyl methacrylate / styrene / benzyl methacrylate (mass ratio: 27 / 5 / 45 / 23, Mw: 45000, acid value: 107 mg KOH / g). (Photopolymerizable compounds) FA-321M: EO-modified bisphenol A dimethacrylate (Hitachi Chemical Co., Ltd., number of EO groups: 10 (average)) FA-024M: Polyalkylene glycol dimethacrylate (Hitachi Chemical Co., Ltd., number of EO groups: 12 (average), number of PO groups: 4 (average)) BPE-200: 2,2-bis(4-(methacryloyloxydiethoxy)phenyl)propane (Shin-Nakamura Chemical Co., Ltd.) (Photopolymerization initiator) B-CIM: 2,2'-Bis(2-chlorophenyl)-4,4',5,5'-Tetraphenylbiimidazole (Hodogaya Chemical Co., Ltd.) (Sensitizer) EAB: 4,4'-bis(diethylamino)benzophenone (manufactured by Hodogaya Chemical Co., Ltd.) [Table 1]

[0107] [Supporting membrane] As a support film for the photosensitive element, support films S1 to S7 (thickness: 16 μm) with the layer structure shown in Table 2 were prepared.

[0108] S1: A 3-layer biaxially oriented polyester film (Toray Industries, Inc., trade name "QS64", thickness of the first and second layers: less than 1 μm) S2: A 3-layer biaxially oriented polyester film (Toray Industries, Inc., trade name "QS66", thickness of the first and second layers: less than 1 μm) S3: Biaxially oriented polyester film with a 2-layer structure (manufactured by Mitsubishi Chemical Corporation, trade name "R-705", thickness of the second layer: less than 1μm) S4: A 3-layer biaxially oriented polyester film (Toray Industries, Inc., trade name "FB40", thickness of the first and second layers: less than 1 μm) S5: A 3-layer biaxially oriented polyester film (Toray Industries, Inc., trade name "QS61", thickness of the first and second layers: less than 1 μm) S6: A 3-layer biaxially oriented polyester film (Toray Industries, Inc., trade name "QS63", thickness of the first and second layers: less than 1 μm) (Surface resistivity of the supporting film) A 10cm × 10cm support film was placed in an environment with a temperature of 23℃ and a humidity of 60±10%. Electrodes were placed on the support film, and the surface resistivity was measured after being placed at 100V for 1 minute using a digital ultra-high resistance / micro-current meter (ADC CORPORATION (ADCMT), trade name "8340A").

[0109] (Average particle size of lubricant) The surface of the support film was observed using a scanning electron microscope “SU-1500” (manufactured by Hitachi, Ltd.), and the average particle size of the lubricant was determined.

[0110] (Number of lubricants) The surface of the support film was observed using a confocal laser microscope “OPTELICS HYBRID” (Lasertec Corporation), and the number of lubricants present in a 150 μm × 150 μm square was determined.

[0111] [Photosensitive element] The solution of the photosensitive resin composition was uniformly coated onto the first layer of the support film using a comma coater. Subsequently, it was dried in a hot air convection dryer at 100°C for 2 minutes to form a photosensitive layer with a thickness of 15 μm. Next, a PE film (manufactured by Tamapoly Co., Ltd., trade name "NF-15A", thickness: 28 μm) was laminated onto the photosensitive layer as a protective film to fabricate the photosensitive element.

[0112] (Evaluation of resist pattern) The copper surface of a copper-clad laminate (manufactured by Hitachi Chemical Co., Ltd., trade name "MLC-E-679"), which consists of copper foil (thickness: 35 μm) laminated on both sides of a glass epoxy material, was acid-washed, washed with water, and then dried under an air stream. The resulting copper-clad laminate was heated to 80°C, and a photosensitive element was laminated with the photosensitive layer in contact with the copper surface while peeling off the protective film. This resulted in a laminate consisting of the copper-clad laminate, the photosensitive layer, and the support film. Lamination was performed using a 120°C hot roller at a pressing pressure of 0.4 MPa and a roller speed of 1.5 m / min.

[0113] Using a glass chrome-type optical instrument with a 41-segment exposure meter, a negative film with a line width / spacing width of 2 / 2 to 20 / 20 (μm) for resolution evaluation, and a projection exposure machine (UX-7 series, manufactured by Ushio Inc.) with a high-pressure mercury lamp, the photosensitive layer of the laminate was exposed at an irradiation energy of 9 residual segments after development, as shown by the 41-segment exposure meter. Next, the support film was peeled off, and the laminate was spray-developed at 30°C for twice the minimum development time with a 1% (w / w) sodium carbonate aqueous solution to remove unexposed areas.

[0114] Three resist patterns with a width of 10 μm, a spacing of 10 μm, and a line length of 18 mm were observed using a scanning electron microscope “SU-1500” (manufactured by Hitachi, Ltd.), and the number of resist defects larger than 1 μm was evaluated.

[0115] [Table 2]

[0116] Symbol Explanation 1-Photosensitive element, 10-Support film, 10a-First side, 10b-Second side, 12, 22-First layer, 14, 24-Second layer, 16-Substrate layer, 20-Photosensitive layer.

Claims

1. A photosensitive element comprising: a support film; and a photosensitive layer formed on a first surface of the support film, wherein The surface resistivity of the first face in the support film is 1 x 10 13 Ω, and the surface resistivity of the second face on the side opposite the first face is 1 x 10 17 Ω. 8 Ω, and the surface resistivity of the second face on the side opposite the first face is 1 x 10 12 Ω.

2. The photosensitive element according to claim 1, wherein the support film has a first layer containing a lubricant on the first surface side, and a second layer containing an antistatic agent and a lubricant on the second surface side.

3. The photosensitive element according to claim 2, wherein the average particle diameter of the lubricant is 1 μm or less.

4. The photosensitive element according to claim 2 or 3, wherein the average particle diameter of the lubricant contained in the first layer is smaller than the average particle diameter of the lubricant contained in the second layer.

5. The photosensitive element according to any one of claims 2 to 4, wherein the support film further has a base material layer between the first layer and the second layer, the base material layer being a layer not containing a lubricant and an antistatic agent.

6. The photosensitive element according to claim 5, wherein the support film is a biaxially oriented polyester film having a three-layer structure.

7. A resist pattern forming method comprising: a lamination step of laminating the photosensitive element according to any one of claims 1 to 6 on a substrate in the order of the photosensitive layer, the support film; an exposure step of forming a photocured portion by irradiating active light to a prescribed portion of the photosensitive layer through the support film; and a development step of removing regions other than the photocured portion in the photosensitive layer.

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

Images