JP2018141903A - Photosensitive resin composition, photosensitive element, and resist pattern forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition featuring excellent resolution and adhesion to a sealing material, and a photosensitive element and a resist pattern forming method featuring excellent measures against electrification and static electricity.SOLUTION: A photosensitive resin composition contains (A) a component: binder polymer, (B) a component: a photopolymerizable compound, and (C) a component: a photopolymerization initiator. The binder polymer contains an ionic liquid-derived structural unit containing no fluorine atom in the molecule, or the photosensitive resin composition further contains ionic liquid containing no fluorine atom in the molecule.SELECTED DRAWING: None

Description

  The present invention relates to a photosensitive resin composition, a photosensitive element using the same, and a resist pattern forming method.

In the field of printed wiring board production, as a resist material used for etching or plating for circuit formation, or as a solder resist for wiring protection of the outermost layer, a photosensitive resin composition or a layer containing this photosensitive resin composition ( Hereinafter, photosensitive elements (photosensitive films) having a structure in which a “photosensitive layer” is formed on a support film and a protective film is disposed on the photosensitive layer are widely used.
For example, the printed wiring board is manufactured by the following procedure using the photosensitive film. That is, first, the photosensitive layer of the photosensitive film is laminated after peeling the protective film on a circuit forming substrate such as a copper-clad laminate. Next, the photosensitive layer is pattern-exposed through a mask film or the like. At this time, the support film is peeled off at any timing before exposure or after exposure. Thereafter, the unexposed portion of the photosensitive layer is dissolved or dispersed with a developer to form a photosensitive resin pattern.
Next, in the case of a circuit forming application, an etching process or a plating process is performed to form a circuit pattern, and the finally cured photosensitive resin portion is peeled and removed.
Here, the etching treatment is a method of removing the cured resist after etching away the metal surface of the circuit forming substrate not covered with the cured resist formed after development. The plating process is a metal surface that has been coated with copper and solder after the plating process such as copper and solder is applied to the metal surface of the circuit-forming substrate that is not covered with the cured resist formed after development. (Semi-additive process: SAP method)).
On the other hand, when used as a solder resist, after forming a pattern of a photosensitive resin, post UV irradiation, thermal curing, etc. are performed to further cure the photosensitive layer and use it as a resist for a permanent insulating layer.

In recent years, in order to further increase the density of electronic devices, attempts have been made to use conventional printed wiring board manufacturing techniques for semiconductor packaging. For example, a FOWLP (Fan-Out Wafer Level Package) is a package having a structure in which fine rewirings are formed on a semiconductor chip by extending outside the outer shape of the chip. FOWLP can be significantly reduced in size and thickness as compared with conventional packages. Application of the above-described photosensitive resin is being promoted in the manufacturing process of these wiring formation and the formation of the rewiring layer.
However, the wiring pattern around the semiconductor is finer than conventional printed wiring board applications, and for example, a resist pattern of 5/5 (unit: μm) or less is required as L / S (line width / space width). Is done. Also, the opening pattern is required to be Φ40 μm or less.
So far, various photosensitive resin compositions have been studied for miniaturization. For example, Patent Document 1 discloses a photosensitive resin composition excellent in sensitivity and resolution by using a binder polymer obtained by polymerizing a specific copolymer component. Patent Document 2 discloses a photosensitive resin composition that can be used to obtain a fine and rectangular opening pattern by using a specific photopolymerization initiator in combination.

JP 2014-134815 A JP 2013-125138 A

  When using the photosensitive resin composition described in the above publication, it is possible to form a finer resist pattern than the conventional one for resolution. It is also required to have excellent adhesion to a sealing material that is a resin. Further, in a package such as FOWLP, since a resist pattern is formed in a state where a semiconductor chip is present, charging or static electricity becomes a problem. If high voltage electricity temporarily flows due to electrostatic discharge, it will lead to destruction of the semiconductor chip.

  For this reason, it is requested | required that the photosensitive resin composition should be excellent especially in adhesiveness with a sealing material, when using it around a semiconductor. Furthermore, measures against charging and static electricity are also required.

  An object of the present disclosure is to provide a photosensitive resin composition excellent in resolution and adhesion to a sealing material, a photosensitive element excellent in charge and static electricity countermeasures, and a method for forming a resist pattern.

［Ｒ_１は、水素原子、炭素原子及び酸素原子を含む有機基を示す。Ｒ_２は、ヒドロキシル基、又は、（メタ）アクリロイル基を含む有機基を示す。］
［５］ 光重合開始剤として、ヘキサアリールビイミダゾール誘導体、アクリジン化合物、アセトフェノン化合物、アシルフォスフィンオキサイド化合物及びオキシムエステル化合物からなる群より選ばれる少なくとも１種を含有する、［１］〜［４］のいずれかに記載の感光性樹脂組成物。
［６］ バインダーポリマーが、分子内に少なくとも一つの不飽和二重結合を有する感光性ポリマーである、［１］〜［５］のいずれかに記載の感光性樹脂組成物。
［７］ （Ｅ）成分：熱硬化剤を更に含有する、［１］〜［６］のいずれかに記載の感光性樹脂組成物。
［８］ 支持体と、該支持体上に形成された［１］〜［７］のいずれかに記載の感光性樹脂組成物を含む感光層と、を備える感光性エレメント。
［９］ ［１］〜［７］のいずれかに記載の感光性樹脂組成物を含む感光層、又は［８］に記載の感光性エレメントの感光層を基板上に積層する感光層形成工程と、感光層の所定部分に活性光線を照射して光硬化部を形成する露光工程と、感光層の所定部分以外の領域を基板上から除去する現像工程と、を有するレジストパターンの形成方法。 As a result of intensive studies on the composition of the binder polymer used in the photosensitive resin composition in order to solve the above problems, the present inventors have found that the above problems can be solved by the following invention.
[1] A photosensitive resin composition containing (A) component: binder polymer, (B) component: photopolymerizable compound, and (C) component: photopolymerization initiator,
The photosensitive resin composition in which a binder polymer contains the structural unit derived from the ionic liquid which does not contain a fluorine atom in a molecule | numerator.
[2] (A) component: binder polymer, (B) component: photopolymerizable compound, (C) component: photopolymerization initiator, (D) component: ionic liquid containing no fluorine atom in the molecule A photosensitive resin composition to contain.
[3] The photosensitive resin composition according to [1] or [2], wherein the ionic liquid is an ionic liquid having a (meth) acryloyl group in the molecule.
[4] The photosensitive resin composition according to any one of [1] to [3], wherein the ionic liquid has a cation having a structure represented by the following general formula (I).

[R ₁ represents an organic group containing a hydrogen atom, a carbon atom, and an oxygen atom. R ₂ represents a hydroxyl group or an organic group containing a (meth) acryloyl group. ]
[5] As a photopolymerization initiator, it contains at least one selected from the group consisting of a hexaarylbiimidazole derivative, an acridine compound, an acetophenone compound, an acylphosphine oxide compound, and an oxime ester compound, [1] to [4] The photosensitive resin composition in any one of 1.
[6] The photosensitive resin composition according to any one of [1] to [5], wherein the binder polymer is a photosensitive polymer having at least one unsaturated double bond in the molecule.
[7] Component (E): The photosensitive resin composition according to any one of [1] to [6], further containing a thermosetting agent.
[8] A photosensitive element comprising a support and a photosensitive layer containing the photosensitive resin composition according to any one of [1] to [7] formed on the support.
[9] A photosensitive layer forming step of laminating a photosensitive layer containing the photosensitive resin composition according to any one of [1] to [7] or a photosensitive layer of the photosensitive element according to [8] on a substrate; A resist pattern forming method comprising: an exposure step of irradiating a predetermined portion of the photosensitive layer with actinic rays to form a photocured portion; and a developing step of removing a region other than the predetermined portion of the photosensitive layer from the substrate.

  According to the present disclosure, a photosensitive resin composition excellent in photosensitivity and resolution, and excellent in charging, electrostatic characteristics, and adhesion to a sealing material, and a photosensitive element and a resist pattern forming method using the same Can be provided.

In this specification, the term “process” is not limited to an independent process, and is included in the term if the intended action of the process is achieved even when it cannot be clearly distinguished from other processes. .
Moreover, the numerical value range shown using "to" in this specification shows the range which includes the numerical value described before and behind "to" as a minimum value and a maximum value, respectively.
Furthermore, when referring to the amount of each component in the composition in the present specification, when there are a plurality of substances corresponding to each component in the composition, the plurality of the components present in the composition unless otherwise specified. Means the total amount of substances.
In the present specification, (meth) acrylic acid means acrylic acid or methacrylic acid, (meth) acrylate means acrylate or a corresponding methacrylate, and (meth) acryloyl group means acryloyl group or methacryloyl group. Means.

<Photosensitive resin composition>
The photosensitive resin composition of the present embodiment contains (A) component: binder polymer, (B) component: photopolymerizable compound, and (C) component: photopolymerization initiator. In the photosensitive resin composition of the present embodiment, the binder polymer contains a structural unit derived from an ionic liquid that does not contain a fluorine atom in the molecule, or the photosensitive resin composition has (D) component: fluorine atom in the molecule. It further contains an ionic liquid that does not contain. Moreover, the photosensitive resin composition of this embodiment may further contain (E) component: a thermosetting agent.

(Ionic liquid that does not contain fluorine element in the molecule)
The ionic liquid of the present embodiment is not particularly limited as long as it does not contain a fluorine element in the molecule. Examples of the cation component include imidazolium ions and pyridinium ions.
The ionic liquid preferably has a (meth) acryloyl group in the molecule. This (meth) acryloyl group is preferably in the structure of the cationic component.

［Ｒ_１は、水素原子、炭素原子及び酸素原子を含む有機基を示す。Ｒ_２は、ヒドロキシル基、又は、（メタ）アクリロイル基を含む有機基を示す。］
また、アニオン成分としては、ＳＯ_３ ⁻基を有するアニオンが上記カチオンとの組み合わせでイオン液体の特性として望ましい。Ｒ_１において、水素原子、炭素原子及び酸素原子を含む有機基としては、例えば、オキシエチレン、オキシプロピレン、アルキルエーテル、グリコール変性鎖等を含む基が挙げられる。Ｒ_２において、ヒドロキシル基、又は、（メタ）アクリロイル基は、例えばアルキレン基を介して、式（１）中の−ＣＨ_２基に結合する。 Moreover, it is preferable that the ionic liquid of (D) component of this embodiment has a cation component of the structure shown by the following general formula (I).

[R ₁ represents an organic group containing a hydrogen atom, a carbon atom, and an oxygen atom. R ₂ represents a hydroxyl group or an organic group containing a (meth) acryloyl group. ]
As the anionic component, SO ₃ ^- anion having a group is desirable as characteristics of the ionic liquid in combination with the above cations. In R ₁ , examples of the organic group containing a hydrogen atom, a carbon atom, and an oxygen atom include groups containing oxyethylene, oxypropylene, alkyl ether, glycol-modified chain, and the like. In R ₂ , the hydroxyl group or the (meth) acryloyl group is bonded to the —CH ₂ group in the formula (1) via, for example, an alkylene group.

  Specifically, AS-100, AS-300, and AS-400 (manufactured by Nippon Emulsifier Co., Ltd., sample name) composed of a hydroxyl group-containing cation component can be mentioned. Examples of the ionic liquid having a (meth) acryloyl group in the component (D) molecule include JI-62C01, JI-62G01, and JI-63F01 (manufactured by Nippon Emulsifier Co., Ltd., sample name).

The ionic liquid may be incorporated by being copolymerized in the binder polymer. In that case, the ionic liquid is present in the composition in a polymer state. Therefore, it effectively works against problems such as bleeding caused by the ionic liquid with respect to various resistances after curing the photosensitive resin composition. In the case of copolymerization, a reactive ionic liquid having a polymerizable group such as a (meth) acryloyl group can be used. The method of copolymerizing the reactive ionic liquid can be performed by general radical polymerization. For example, there are techniques such as solution polymerization, suspension polymerization, emulsion polymerization, bulk polymerization, and precipitation polymerization.
The content of the ionic liquid of component (D) in the photosensitive resin composition of the present embodiment is preferably 0.1 to 30% by mass, and 0.5 to 20% by mass in the photosensitive resin composition. More preferably, it is 1 to 15% by mass. When the ionic liquid is taken into the binder polymer, the content of the structural unit derived from the ionic liquid in the binder polymer is preferably in the same range.
When the content of the ionic liquid is 30% by mass or less, resolution and adhesion are improved, and the inherent characteristics of the photosensitive resin tend to be exhibited well. Further, when the content is 0.1% by mass or more, the effects of surface hydrophilicity, charging, and electrostatic characteristics tend to be obtained more favorably.

((A) component: binder polymer)
Component (A) of this embodiment: The binder polymer is not particularly limited as long as it has alkali developability, but desirably, a structural unit based on (meth) acrylic acid or (meth) acrylic acid ester, Includes structural units derived from styrene or styrene derivatives.
In particular, a structural unit having a benzene ring in the molecule is preferably contained, and a structural unit derived from benzyl (meth) acrylate, styrene, or a styrene derivative is preferably contained.
The acid value in the binder polymer is preferably 50 to 250 mgKOH / g, and more preferably 70 to 200 mgKOH / g, from the viewpoint of achieving both developability and peeling properties.

  Specific examples of components of (meth) acrylic acid, (meth) acrylic acid ester, styrene, and / or styrene derivatives include styrene, vinyltoluene, α-methylstyrene, p-methylstyrene, p- Polymerizable styrene derivatives such as ethyl styrene, acrylic acid, methacrylic acid, (meth) acrylic acid alkyl ester, (meth) acrylic acid benzyl ester, (meth) acrylic acid benzyl ester derivative, (meth) acrylic acid cycloalkyl ester, (Meth) acrylic acid furfuryl ester, (meth) acrylic acid tetrahydrofurfuryl ester, (meth) acrylic acid isobornyl ester, (meth) acrylic acid adamantyl ester, (meth) acrylic acid dicyclopentanyl ester, (meta ) Dimethylaminoethyl acrylate Steal, (meth) acrylic acid diethylaminoethyl ester, (meth) acrylic acid glycidyl ester, 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 monoester such as monomethyl maleate, monoethyl maleate, monoisopropyl maleate, fumaric acid, cinnamic acid , Α-cyanocinnamic acid, itaconic acid, crotonic acid, propiolic acid.

Examples of alkyl groups in (meth) acrylic acid alkyl esters include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl And structural isomers thereof. From the viewpoint of further improving the peeling characteristics, the alkyl group is preferably one having 1 to 4 carbon atoms.
Specific examples of the (meth) acrylic acid alkyl ester include (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid propyl ester, (meth) acrylic acid butyl ester, (meth) acrylic acid. Pentyl ester, (meth) acrylic acid hexyl ester, (meth) acrylic acid heptyl ester, (meth) acrylic acid octyl ester, (meth) acrylic acid 2-ethylhexyl ester, (meth) acrylic acid nonyl ester, (meth) acrylic acid Examples include decyl ester, (meth) acrylic acid undecyl ester, and (meth) acrylic acid dodecyl ester. These may be used alone or in any combination of two or more.

  The average weight molecular weight (Mw) of the binder polymer is 10,000 to 100,000, preferably 20,000 to 100,000, more preferably 20,000 to 80,000, still more preferably 25,000 to 60,000. When the molecular weight is 100,000 or less, the resolution and developability tend to be further improved, and when the molecular weight is 10,000 or more, the coating property tends to be further improved.

The binder polymer of the component (A) may further have a (meth) acrylic acid alkyl ester having a C 1-30 alkyl group as a structural unit. By introducing an alkyl chain, the trade-off between flexibility and peelability can be eliminated. 1-10 are preferable and, as for the number of carbon atoms, 2-6 are more preferable.
The weight average molecular weight of the binder polymer is measured by gel permeation chromatography (GPC) (converted with a calibration curve using standard polystyrene).
In the photosensitive resin composition of the present embodiment, as the binder polymer, one kind of binder polymer may be used alone, or two or more kinds of binder polymers may be used in any combination.
As a binder polymer in the case of using two or more types in combination, for example, two or more types of binder polymers comprising different copolymer components (including different monomer units as copolymer components), two or more types of different weight average molecular weights Examples of the binder polymer include two or more binder polymers having different degrees of dispersion. In addition, a polymer having a multimode molecular weight distribution described in JP-A No. 11-327137 can also be used.

The content of the (A) binder polymer in the photosensitive resin composition of the present embodiment is preferably 20 to 90% by mass, more preferably 30 to 80% by mass in the photosensitive resin composition, More preferably, it is 40-65 mass%.
There exists a tendency for the moldability of a film to be excellent in the content rate of a binder polymer being 20 mass% or more. Moreover, there exists a tendency which is excellent in a sensitivity and the resolution in it being 90 mass% or less.
In the photosensitive resin composition of the present embodiment, (A) the binder polymer may be a photosensitive polymer having at least one unsaturated double bond in the molecule. As such a polymer, for example, there is an acid-modified vinyl group-containing epoxy resin. A resin obtained by modifying an epoxy resin with a vinyl group-containing monocarboxylic acid by a known method can be used. Examples of the epoxy resin include phenol novolac type epoxy resin, cresol novolac type epoxy resin, bis A type epoxy resin, bis F type epoxy resin, bis F type novolac epoxy resin, and salicylaldehyde type epoxy resin.

((B) component: photopolymerizable compound)
Subsequently, (B) the photopolymerizable compound will be described.
The photopolymerizable compound of this embodiment has at least one ethylenically unsaturated bond and is not particularly limited as long as it is a photopolymerizable compound, but improves alkali developability, resolution, and release characteristics after curing. From the viewpoint of making it, it is preferable to include at least one bisphenol A type (meth) acrylate compound.
Specific examples of bisphenol A-based (meth) acrylate compounds include 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane and 2,2-bis (4-((meth) acryloxypoly). Propoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxypolybutoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxypolyethoxypolypropoxy) phenyl) propane, etc. Is mentioned. Among these, 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane is preferable from the viewpoint of further improving the resolution and peeling properties.
Of these, 2,2-bis (4-((meth) acryloxydipropoxy) phenyl) propane is commercially available as BPE-200 (manufactured by Shin-Nakamura Chemical Co., Ltd., product name). 2,2-bis (4- (methacryloxypentaethoxy) phenyl) propane is either BPE-500 (manufactured by Shin-Nakamura Chemical Co., Ltd., product name) or FA-321M (Hitachi Chemical Co., Ltd.). It is commercially available as a product name manufactured by Kogyo Co., Ltd.
These bisphenol A-based (meth) acrylate compounds are used singly or in combination of two or more.

The content of the bisphenol A-based (meth) acrylate compound in the photopolymerizable compound is preferably 30 to 100% by mass, and 50 to 90% by mass in the total mass of the (B) photopolymerizable compound. It is more preferable. The resolution of a resist improves more because the content rate is in such a range.
The content of the photopolymerizable compound in the photosensitive resin composition is preferably 3 to 70% by mass, more preferably 10 to 60% by mass, and still more preferably 25 to 55% by mass. .
There exists a tendency for a sensitivity and a resolution to be excellent in the content rate of a photopolymerizable compound being 3 mass% or more. Moreover, there exists a tendency which is excellent in the moldability of a film as it is 70 mass% or less.

As (B) photopolymerizable compounds other than bisphenol A-based (meth) acrylate compounds, polyalkylene glycol di (meth) acrylate having at least one of (poly) oxyethylene chain and (poly) oxypropylene chain in the molecule is used. A cured product (cured film) further comprising at least one kind, and further comprising a polyalkylene glycol di (meth) acrylate having both a (poly) oxyethylene chain and a (poly) oxypropylene chain in the molecule. It is preferable for improving the flexibility.
Moreover, nonyl phenoxy polyethylene oxyacrylate, a phthalic acid type compound, (meth) acrylic acid polyol ester, (meth) acrylic acid alkyl ester, etc. are mentioned. Especially, it is preferable that it is at least 1 sort (s) chosen from nonyl phenoxy polyethylene oxyacrylate and a phthalic acid type compound from a viewpoint which improves resolution, adhesiveness, a resist shape, and the peeling characteristic after hardening with sufficient balance.
However, since the refractive index of these compounds is relatively low, a smaller content is preferable.
Polyalkylene glycol di (meth) acrylates include FA-023M (trade name, manufactured by Hitachi Chemical Co., Ltd.), FA-024M (trade name, manufactured by Hitachi Chemical Co., Ltd.), NK ester HEMA-9P (Shin Nakamura Chemical Co., Ltd.) Company name, sample name) and the like. These can be used alone or in combination of two or more.

  Nonylphenoxypolyethyleneoxyacrylate includes, for example, nonylphenoxytriethyleneoxyacrylate, nonylphenoxytetraethyleneoxyacrylate, nonylphenoxypentaethyleneoxyacrylate, nonylphenoxyhexaethyleneoxyacrylate, nonylphenoxyheptaethyleneoxyacrylate, nonylphenoxyoctaethyleneoxy Examples thereof include acrylate, nonylphenoxynonaethyleneoxyacrylate, nonylphenoxydecaethyleneoxyacrylate, and nonylphenoxyundecaethyleneoxyacrylate.

  Examples of phthalic acid compounds include γ-chloro-β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate, β-hydroxyethyl-β ′-(meth) acryloyloxyethyl-o. -Phthalate and [beta] -hydroxypropyl- [beta] '-(meth) acryloyloxyethyl-o-phthalate, among which [gamma] -chloro- [beta] -hydroxypropyl- [beta]'-(meth) acryloyloxyethyl-o-phthalate Is preferred. γ-Chloro-β-hydroxypropyl-β′-methacryloyloxyethyl-o-phthalate is commercially available as FA-MECH (manufactured by Hitachi Chemical Co., Ltd., product name).

  Examples of the (meth) acrylic acid polyol ester include trimethylolpropane polyethoxytri (meth) acrylate, trimethylolpropane polypropoxytri (meth) acrylate, trimethylolpropane polybutoxytri (meth) acrylate, and trimethylolpropane polyethoxy. Polypropoxytri (meth) acrylate, trimethylolethane polyethoxytri (meth) acrylate, trimethylolethane polypropoxytri (meth) acrylate, trimethylolethanepolybutoxytri (meth) acrylate, trimethylolethane polyethoxypolypropoxytri ( (Meth) acrylate, pentaerythritol polyethoxytri (meth) acrylate, pentaerythritol polypropoxytri (meth) acrylate Rate, pentaerythritol polybutoxytri (meth) acrylate, pentaerythritol polyethoxypolypropoxytri (meth) acrylate, glyceryl polyethoxytri (meth) acrylate, glyceryl polypropoxytri (meth) acrylate, glyceryl polybutoxytri (meth) acrylate And glyceryl polyethoxypolypropoxy tri (meth) acrylate.

((C) component: photopolymerization initiator)
Next, (C) the photopolymerization initiator of this embodiment will be described.
Examples of the photopolymerization initiator as component (C) include hexaarylbiimidazole derivatives and acridine compounds having one or more acridinyl groups.
Examples of hexaarylbiimidazole derivatives 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, 2- (o-chlorophenyl) -bis-4,5- (3,4-dimethoxyphenyl) -biimidazole, 2,2′-bis- (2-fluorophenyl) -4,4 ', 5,5'-tetrakis- (3-methoxyphenyl) -biimidazole, 2,2'-bis- (2,3-difluoromethylphenyl) -4,4', 5 5'-tetrakis- (3-methoxyphenyl) -biimidazole, 2,2'-bis- (2,4-difluorophenyl) -4,4 ', 5,5'-tetrakis- (3-methoxyphenyl)- Biimidazole, 2,2′-bis- (2,5-difluorophenyl) -4,4 ′, 5,5′-tetrakis- (3-methoxyphenyl) -biimidazole and the like can be mentioned. Among these, 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer is preferable from the viewpoint of sensitivity and resolution.

  Examples of the acridine compound 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-acridinyl) ethane, 1,4-bis (9-acridinyl) butane, 1,6- Bis (9-acridinyl) hexane, 1,8-bis (9-acridinyl) octane, 1,10-bis (9-acridinyl) decane, 1,12-bis (9-acridinyl) dodecane, 1,14-bis ( 9-Acridinyl) tetradecane, 1,16-bis (9-acridinyl) hexadecane 1,18-bis (9-acridinyl) octadecane, bis (9-acridinyl) alkanes such as 1,20-bis (9-acridinyl) eicosane, 1,3-bis (9-acridinyl) -2-oxapropane, , 3-bis (9-acridinyl) -2-thiapropane, 1,5-bis (9-acridinyl) -3-thiapentane and the like. These are used alone or in combination of two or more.

  Examples of other photopolymerization initiators include acetophenone compounds, acylphosphine oxide compounds, benzophenones, benzophenones such as 4,4′-bis (diethylamino) benzophenone, 2-benzyl-2-dimethylamino-1- (4 -Morpholinophenyl) -butanone-1,2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propanone-1 and other aromatic ketones, quinones such as alkylanthraquinones, and benzoins such as benzoin alkyl ethers Ether compounds, benzoin compounds such as benzoin and alkylbenzoin, benzyl derivatives such as benzyldimethyl ketal, N-phenylglycine, N-phenylglycine derivatives, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, Acylphosphine oxide photopolymerization initiators such as bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O— Benzoyloxime)], ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime) and the like. . These can be used by mixing with a hexaarylbiimidazole derivative or an acridine compound.

The content of the photopolymerization initiator is preferably 0.1 to 10% by mass, more preferably 1 to 5% by mass, and still more preferably 2 to 4.5% by mass.
When this content rate is within the above range, both photosensitivity and resolution can be achieved at a higher level.

  (E) component: As a thermosetting agent, thermosetting compounds, such as an epoxy compound, a melamine compound, a urea compound, an oxazoline compound, block type isocyanate, are mentioned, for example. Examples of the epoxy compound include bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, novolac type epoxy resin, bisphenol S type epoxy resin, and biphenyl type epoxy resin. , Naphthalene type epoxy resin, dicyclo type epoxy resin, hydantoin type epoxy resin, heterocyclic epoxy resin such as triglycidyl isocyanurate, and bixylenol type epoxy resin. Examples of the melamine compound include triaminotriazine, hexamethoxymelamine, hexabutoxylated melamine and the like. Examples of the urea compound include dimethylol urea.

The photosensitive resin composition preferably further contains a sensitizer. Thereby, the curing sensitivity of the photosensitive resin composition is further improved.
Examples of the sensitizer include, for example, dialkylaminobenzophenones, pyrazolines, anthracene, coumarins, xanthones, oxazoles, benzoxazoles, thiazoles, benzothiazoles, triazoles, stilbenes, triazines, thiophenes , Naphthalimides, and triarylamines. These are used individually by 1 type or in combination of 2 or more types.
In particular, when the photosensitive layer is exposed using an actinic ray of 390 to 420 nm, the sensitizer is a group consisting of pyrazolines, anthracenes, coumarins and triarylamines from the viewpoint of sensitivity and adhesion. It is preferable to include at least one selected from the group consisting of pyrazolines, anthracenes, and triarylamines, and it is more preferable to include at least one selected from the group consisting of triarylamines.
The content of the sensitizer is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, and still more preferably 0.1 to 3% by mass.
Sensitivity and resolution are further improved when the content of the sensitizer is 0.01% by mass or more. Moreover, it is suppressed that a resist shape turns into an inverted trapezoid because it is 10 mass% or less, and adhesiveness improves.

It is preferable that the photosensitive resin composition further contains an amine compound. Thereby, the sensitivity of the photosensitive resin composition is further improved.
Examples of the amine compound include bis [4- (dimethylamino) phenyl] methane, bis [4- (diethylamino) phenyl] methane, and leucocrystal violet. These are used individually by 1 type or in combination of 2 or more types.
When the photosensitive resin composition contains an amine compound component, the content is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, More preferably, the content is 2% by mass.
Sensitivity improves more because content of an amine compound is 0.01 mass% or more. Moreover, it is suppressed that an excess amine compound component precipitates as a foreign material after film formation because it is 10 mass% or less.

The photosensitive resin composition can contain other components as needed in addition to the above components. Examples of other components include cationic polymerization initiators, dyes such as malachite green, tribromophenyl sulfone, photochromic agents, thermochromic inhibitors, plasticizers such as p-toluenesulfonamide, pigments, fillers, and antifoaming agents. , Flame retardants, stabilizers, adhesion-imparting agents, leveling agents, peeling accelerators, antioxidants, fragrances, imaging agents, and thermal crosslinking agents.
These are used individually by 1 type or in combination of 2 or more types.
Moreover, it is preferable that content of these other components shall be about 0.01-20 mass%, respectively.

The photosensitive resin composition can contain at least one organic solvent. As the organic solvent, a commonly used organic solvent can be used without any particular limitation. Specific examples include methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N-dimethylformamide, propylene glycol monomethyl ether, and mixed solvents thereof.
For example, (A) a binder polymer, (B) a photopolymerizable compound, (C) a photopolymerization initiator and other components of a photosensitive resin composition are dissolved in an organic solvent, and a solid content of about 30 to 60% by mass (Hereinafter referred to as “coating liquid”).
In addition, solid content means the remaining component remove | excluding the volatile component from the solution (photosensitive resin composition).

(Photosensitive element)
<Supporting film and protective film>
The photosensitive resin composition of this embodiment can be used also as a photosensitive element provided with a support body and the photosensitive layer containing the photosensitive resin composition formed on this support body.
When using the photosensitive element of this embodiment, generally, after laminating a photosensitive layer on a substrate, exposure is performed without peeling off the support (support film).
As the support film, a polymer film having heat resistance and solvent resistance such as polyester such as polyethylene terephthalate, polypropylene, and polyethylene can be used, but polyethylene terephthalate (PET) is preferably used from the viewpoint of versatility.
In the present embodiment, particles having a diameter of 5 μm or more contained in the support film are adjusted to 5 particles / mm ² or less, the haze is set to 0.01 to 1.0%, and at the same time, the resin layer containing fine particles is formed. A multilayer support film provided is particularly suitable. As a result, the slipperiness of the surface of the support film is improved, and the suppression of light scattering during exposure can be achieved at a higher level in a balanced manner. The average particle diameter of the fine particles is 5 μm or less, preferably 1 μm or less, particularly preferably 0.1 μm or less, and the lower limit is not particularly limited, but is preferably 0.001 μm or more.
As a commercially available general industrial film that can be used as such a support film, for example, “QS-48” (manufactured by Toray Industries, Inc., which is a biaxially oriented PET film having a three-layer structure in which the outermost layer contains fine particles). (Trade name), "HTF-01" (manufactured by Teijin DuPont Films, Inc., trade name), biaxially oriented PET film "A-1517" (Toyobo Co., Ltd.) having a layer containing fine particles on one side Product name).

The thickness of the support film is preferably 1 to 100 μm, more preferably 5 to 50 μm, and still more preferably 5 to 30 μm. When the thickness of the support film is 1 μm or more, the support film is hardly broken when the support film is peeled off. Moreover, the fall of the resolution can be suppressed because it is 100 micrometers or less.
The photosensitive element may further include a protective film as necessary. As the protective film, it is preferable to use a film in which the adhesive force between the photosensitive layer and the protective film is smaller than the adhesive force between the photosensitive layer and the support film. It is preferable to use it. Specific examples include inert polyolefin films such as polyethylene and polypropylene. From the viewpoint of peelability from the photosensitive layer, a polyethylene film is preferred. Although the thickness of a protective film changes with uses, it is preferable that it is about 1-100 micrometers.

<Photosensitive element manufacturing method>
The photosensitive element can be manufactured as follows, for example. Components of the photosensitive resin composition such as (A) binder polymer, (B) photopolymerizable compound, and (C) photopolymerization initiator are dissolved in an organic solvent, and a coating solution having a solid content of about 30 to 60% by mass is obtained. It can be manufactured by a manufacturing method including preparing, coating a coating solution on a support film to form a coating layer, and drying the coating layer to form a photosensitive layer.
Application of the coating liquid onto the support can be performed by a known method such as a roll coater, comma coater, gravure coater, air knife coater, die coater, or bar coater.
The drying of the coating layer is not particularly limited as long as at least a part of the organic solvent can be removed from the coating layer. For example, it is preferably performed at 70 to 150 ° C. for about 5 to 30 minutes. After drying, the amount of the remaining organic solvent in the photosensitive layer is preferably 2% by mass or less from the viewpoint of preventing the diffusion of the organic solvent in the subsequent step.
Although the thickness of the photosensitive resin layer (photosensitive layer) in the photosensitive element can be appropriately selected depending on the application, it is preferably 1 to 100 μm, more preferably 1 to 50 μm in terms of the thickness after drying, More preferably, it is 5-40 micrometers.
Industrial coating becomes easy and productivity improves because the thickness of a photosensitive layer is 1 micrometer or more. Moreover, adhesiveness and resolution improve by being 100 micrometers or less.
The transmittance of the photosensitive layer with respect to ultraviolet rays is preferably 5 to 75%, more preferably 10 to 65%, and still more preferably 15 to 55% with respect to ultraviolet rays having a wavelength of 365 nm.
Adhesiveness improves more because this transmittance | permeability is 5% or more. Further, when the transmittance is 75% or less, the resolution is further improved. The transmittance can be measured with a UV spectrometer. Examples of the UV spectrometer include a 228A type W beam spectrophotometer manufactured by Hitachi, Ltd.

The form of the photosensitive element is not particularly limited. For example, it may be in the form of a sheet, or may be in a state of being wound up in a roll shape around a core.
When it winds up in roll shape, it is preferable to wind up so that a support film may become an outer side. Examples of the winding core include plastics such as polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, and ABS resin (acrylonitrile-butadiene-styrene copolymer). From the viewpoint of end face protection, it is preferable to install an end face separator on the end face of the roll-shaped photosensitive element roll thus obtained, and it is preferable to install a moisture-proof end face separator from the standpoint of edge fusion resistance. Moreover, as a packaging method, it is preferable to wrap and package in a black sheet with low moisture permeability.
The photosensitive element can be suitably used, for example, in a resist pattern manufacturing method described later. Especially, it is suitable for the application to the manufacturing method which forms a circuit by plating processing.

<Resist pattern manufacturing method>
The resist pattern manufacturing method of this embodiment includes (i) a photosensitive layer forming step of forming a photosensitive layer which is a coating film of a photosensitive resin composition on a substrate, and (ii) an actinic ray on at least a part of the photosensitive layer. Irradiation and photocuring, and (iii) a development step of removing a non-cured portion of the photosensitive layer from the substrate to form a resist pattern made of a cured product derived from the photosensitive layer, and necessary Depending on the configuration, other steps are included.

(I) Photosensitive layer forming step In the photosensitive layer forming step, a photosensitive layer that is a coating film of a photosensitive resin composition is formed on a substrate. Although it does not restrict | limit especially as a board | substrate, Usually, die pads (base material for lead frames), such as a circuit formation board | substrate provided with the insulating layer and the conductor layer formed on the insulating layer, or an alloy base material are used.
The method for forming the photosensitive layer on the substrate can be performed, for example, by removing the protective film from the photosensitive element and then pressing the photosensitive layer of the photosensitive element to the substrate while heating. Thereby, a laminate comprising the substrate, the photosensitive layer and the support, and these are sequentially laminated is obtained.
This photosensitive layer forming step is preferably performed under reduced pressure from the viewpoint of adhesion and followability. The photosensitive layer or the substrate is preferably heated at a temperature of 70 to 130 ° C. during the pressure bonding. The pressure bonding is preferably performed at a pressure of about 0.1 to 1.0 MPa (about 1 to 10 kgf / cm ² ), but these conditions are appropriately selected as necessary. If the photosensitive layer is heated to 70 to 130 ° C., it is not necessary to preheat the substrate in advance, but the substrate can be preheated in order to further improve the adhesion and followability.

(Ii) Exposure Step In the exposure step, at least a part of the photosensitive layer formed on the substrate is irradiated with actinic rays, so that the portion irradiated with actinic rays is photocured to form a latent image. .
Examples of the exposure method include a method of irradiating an actinic ray in an image form through a negative or positive mask pattern called an artwork (mask exposure method). Alternatively, a method of irradiating actinic rays in the form of an image by a direct drawing exposure method such as an LDI (Laser Direct Imaging) exposure method or a DLP (Digital Light Processing) exposure method may be employed.
As the actinic ray light source, a known light source can be used. 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, a semiconductor laser, etc. Those that effectively emit ultraviolet light and visible light are used.

(Iii) Development Step In the development step, a resist pattern made of a cured product obtained by photocuring the photosensitive layer is formed on the substrate by removing an uncured portion of the photosensitive layer from the substrate.
When a support film is present on the photosensitive layer, the support film is removed, and then unexposed portions other than the exposed portions are removed (developed). Development methods include wet development and dry development, but wet development is widely used.
In the case of wet development, development is performed by a known development method using a developer corresponding to the photosensitive resin composition. Examples of the developing method include a method using a dipping method, a paddle method, a spray method, brushing, slapping, scrubbing, rocking immersion, and the like. From the viewpoint of improving resolution, the high pressure spray method is most suitable. You may develop by combining these 2 or more types of methods.
The configuration of the developer is appropriately selected according to the configuration of the photosensitive resin composition. For example, an alkaline aqueous solution, an aqueous developer, and an organic solvent developer can be used.
The alkaline aqueous solution is safe and stable when used as a developer, and has good operability. Examples of the base of the alkaline aqueous solution include alkali hydroxides such as lithium, sodium, or potassium hydroxide; alkali carbonates such as lithium, sodium, potassium, or ammonium carbonate or bicarbonate; potassium phosphate, sodium phosphate, and the like. Alkali metal phosphates; alkali metal pyrophosphates such as sodium pyrophosphate and potassium pyrophosphate are used.

As alkaline aqueous solution, 0.1-5 mass% dilute solution of sodium carbonate, 0.1-5 mass% dilute solution of potassium carbonate, 0.1-5 mass% dilute solution of sodium hydroxide, 0.1-5 A dilute solution of mass% sodium tetraborate is preferred.
The pH of the alkaline aqueous solution is preferably in the range of 9 to 11, and the temperature is adjusted according to the alkali developability of the photosensitive layer. In the alkaline aqueous solution, a surfactant, an antifoaming agent, a small amount of an organic solvent for promoting development, and the like may be mixed.

The aqueous developer is, for example, a developer composed of water or an alkaline aqueous solution and one or more organic solvents. Here, as the base of the alkaline aqueous solution, in addition to the substances described above, for example, borax, sodium metasilicate, tetramethylammonium hydroxide, ethanolamine, ethylenediamine, diethylenetriamine, 2-amino-2-hydroxymethyl-1 , 3-propanediol, 1,3-diaminopropanol-2, morpholine and the like.
The pH of the aqueous developer is preferably as low as possible within a range where development is sufficiently performed, preferably 8 to 12, and more preferably 9 to 10.
Examples of the organic solvent used in the aqueous developer include acetone, ethyl acetate, alkoxyethanol having an alkoxy group having 1 to 4 carbon atoms, ethyl alcohol, isopropyl alcohol, butyl alcohol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl ether. Etc. These are used alone or in combination of two or more. In general, the concentration of the organic solvent in the aqueous developer is preferably 2 to 90% by mass, and the temperature can be adjusted according to alkali developability. A small amount of a surfactant, an antifoaming agent or the like can be mixed in the aqueous developer.

Examples of the organic solvent developer include organic solvents such as 1,1,1-trichloroethane, N-methylpyrrolidone, N, N-dimethylformamide, cyclohexanone, methyl isobutyl ketone, and γ-butyrolactone. It is preferable to add water to these organic solvents in the range of 1 to 20% by mass in order to prevent ignition.
In this embodiment, after removing an unexposed portion in the development step, the resist pattern is further cured by heating at about 60 to 250 ° C. or exposure at about 0.2 to 10 J / cm ² as necessary. May be.

<Method for manufacturing printed wiring board>
The printed wiring board manufacturing method of the present embodiment forms a conductor pattern by etching or plating a circuit forming substrate on which a resist pattern is formed by the above-described resist pattern forming method.

Etching and plating of the circuit forming substrate are performed on the conductor layer of the circuit forming substrate and the like using the formed resist pattern as a mask. Etching solutions used for etching include cupric chloride solution, ferric chloride solution, alkaline etching solution, and hydrogen peroxide etching solution. It is preferable to use an iron solution.
Moreover, as a plating method in the case of plating, for example, copper plating such as copper sulfate plating and copper pyrophosphate plating, solder plating such as high-throw solder plating, watt bath (nickel sulfate-nickel chloride) plating, nickel sulfamate, etc. And nickel plating, hard gold plating, and gold plating such as soft gold plating.

After completion of etching or plating, the resist pattern can be peeled off with a stronger alkaline aqueous solution than the alkaline aqueous solution used for development, for example. As this strongly alkaline aqueous solution, for example, a 1 to 10% by mass sodium hydroxide aqueous solution, a 1 to 10% by mass potassium hydroxide aqueous solution and the like are used. Examples of the peeling method include an immersion method and a spray method, and the immersion method and the spray method may be used alone or in combination. A printed wiring board is obtained as described above.
The printed wiring board manufactured by the method for manufacturing a printed wiring board of the present embodiment may be a multilayer printed wiring board or may have a small diameter through hole.

  Hereinafter, the present disclosure will be specifically described by way of examples. However, the present disclosure is not limited to these examples. Unless otherwise specified, “part” and “%” are based on mass.

<Synthesis example>
(Synthesis of binder polymer (A-1))
A polymerizable monomer (monomer) 135 g of methacrylic acid, 225 g of styrene, 115 g of benzyl methacrylate, and 25 g of reactive ionic liquid JI-62C01 (non-volatile content 50%) (mass ratio 27/45/23/5) A solution was prepared by mixing 3.5 g of azobisisobutyronitrile. Further, a solution b was prepared by mixing 2.0 g of azobisisobutyronitrile with a mixed solution (mass ratio 3: 2) of 45 g of methyl cellosolve and 30 g of toluene. A solution c was prepared in the same manner as the preparation of the solution b.
Into a flask equipped with a stirrer, reflux condenser, thermometer, dropping funnel and nitrogen gas introduction tube, 500 g of a mixed solution of 300 g of methyl cellosolve and 200 g of toluene (mass ratio 3: 2) was added, and nitrogen gas was introduced into the flask. While stirring, the mixture was stirred and heated to 80 ° C.
The solution a was added dropwise to the mixed solution in the flask over 4 hours, and then kept at 80 ° C. for 2 hours with stirring. Next, after the solution b was dropped into the solution in the flask over 10 minutes, the solution in the flask was kept at 80 ° C. for 2 hours while stirring. Further, the temperature of the solution in the flask was raised to 90 ° C. over 30 minutes, and the solution c was added dropwise over 10 minutes, then kept at 90 ° C. for 2 hours, and then cooled to obtain a binder polymer (A-1). Solution was obtained.
The binder polymer (A-1) had a non-volatile content (solid content) of 43.8% by mass and a weight average molecular weight of 48,000. The weight average molecular weight was measured by gel permeation chromatography (GPC) and derived by conversion using a standard polystyrene calibration curve. The GPC conditions are shown below.

GPC condition pump: Hitachi L-6000 type (manufactured by Hitachi, Ltd.)
Column: The following three total Gelpack GL-R420
Gelpack GL-R430
Gelpack GL-R440 (Hitachi Chemical Co., Ltd., trade name)
Eluent: Tetrahydrofuran Measurement temperature: 40 ° C
Flow rate: 2.05 mL / min Detector: Hitachi L-3300 type RI (manufactured by Hitachi, Ltd.)

(Synthesis of binder polymer (A-2))
The polymerizable monomer (monomer) was changed to 135 g of methacrylic acid, 225 g of styrene, 90 g of benzyl methacrylate, and 50 g of reactive ionic liquid JI-62C01 (non-volatile content 50%) (mass ratio 27/45/18/10). The binder polymer (A-2) solution was obtained under the same conditions as the binder polymer (A-1).

(Synthesis of binder polymer (A-3))
Other than changing the polymerizable monomer (monomer) to 135 g of methacrylic acid, 25 g of methyl methacrylate, 225 g of styrene, and 115 g of benzyl methacrylate (mass ratio 27/5/45/23), the binder polymer (A-1 ) To obtain a binder polymer (A-3) solution.

(Synthesis of binder polymer (A-4))
A binder polymer under the same conditions as the binder polymer (A-1) except that the polymerizable monomer (monomer) was changed to 125 g of methacrylic acid, 190 g of methyl methacrylate, and 185 g of styrene (mass ratio 25/38/37). A solution of (A-4) was obtained.

<Examples 1-4 and Comparative Examples 1-2>
[Preparation of photosensitive resin composition]
(A) A-1 to A-4 obtained above as a binder polymer, (B) B-1 shown below as a photopolymerizable compound, (C) C-1 shown below as a photopolymerization initiator (D) D-1 or D-2 shown below as an ionic liquid containing no fluorine atom in the molecule, and the components shown below as the other components, respectively, The photosensitive resin compositions of Examples 1 to 4 and Comparative Examples 1 to 2 were prepared by mixing in (number of blending parts). In addition, the compounding quantity (number of compounding parts) of (A) binder polymer shown in Table 1 is the mass (solid content) of non-volatile matter.

(B) Photopolymerizable compound B-1: 2,2-bis (4- (methacryloxypentaethoxy) phenyl) propane (10 mol EO modified product)
[FA-321M (product name) manufactured by Hitachi Chemical Co., Ltd.]
(C) Photopolymerization initiator C-1: 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenylbisimidazole [B-CIM (manufactured by Hampton, product name)]
(D) Ionic liquid D-1 containing no fluorine atom in the molecule: Non-fluorine-based reactive ionic liquid JI-62C01 (manufactured by Nippon Emulsifier Co., Ltd., sample name)
D-2: Non-fluorinated ionic liquid AS-300 (manufactured by Nippon Emulsifier Co., Ltd., sample name)
(Other)
Sensitizer: 9,10 dibutoxyanthracene [DBA (manufactured by Kawasaki Kasei Kogyo Co., Ltd., product name)]
Amine compound: leuco crystal violet [LCV (manufactured by Yamada Chemical Co., Ltd., product name)]
Dye: Malachite Green [MKG (Osaka Organic Chemical Co., Ltd., product name)]
Polymerization inhibitor: tert-butylcatechol [TBC (product name) manufactured by Wako Pure Chemical Industries, Ltd.]
Additive: N-phenylglycine [NPG (manufactured by Tokyo Chemical Industry Co., Ltd., product name)]
Additive: Tribromomethylphenylsulfone [TPS (Changzhou Power Electronics New Materials Co., Ltd., product name)]
Additive: p-Toluenesulfonamide [PTSA (Wako Pure Chemical Industries, Ltd., product name)]
Additive: Benzotriazole derivative [SF-808H (manufactured by Sanwa Kasei Kogyo Co., Ltd., product name)]

<Production of photosensitive element>
The photosensitive resin composition obtained above is uniformly coated on the support film shown below, dried by a hot air convection dryer at 70 ° C. and 110 ° C., and the film thickness after drying is 25 μm. A layer was formed.
As the support film, FB-40: polyethylene terephthalate, thickness 16 μm, (product name, manufactured by Toray Industries, Inc.) was used. A protective film (manufactured by Tamapoly Co., Ltd., product name “NF-15”) is laminated on the photosensitive layer, and a photosensitive element in which a polyethylene terephthalate film (support film), a photosensitive layer, and a protective film are sequentially laminated. I got each.

<Production of laminate>
A copper-clad laminate (substrate, manufactured by Hitachi Chemical Co., Ltd., trade name “MCL-E-679”), which is a glass epoxy material in which copper foil (thickness: 35 μm) is laminated on both sides, is subjected to surface roughening treatment liquid “MEC”. Surface treatment was performed using “Hetch Bond CZ-8100” (trade name, manufactured by MEC Co., Ltd.), followed by water washing, pickling and water washing, followed by drying with an air stream. The surface-treated copper clad laminate was heated to 80 ° C., and the photosensitive element obtained above was laminated so that the photosensitive layer was in contact with the copper surface while peeling off the protective film. In this way, the laminated body laminated | stacked in order of the copper clad laminated board, the photosensitive layer, and the support film was obtained for every Example.
Lamination was performed using a 110 ° C. heat roll at a pressure of 0.4 MPa and a roll speed of 1.0 m / min.

<Evaluation>
Using the laminate obtained above as a test piece, the following tests were conducted. The results are shown in Table 2.

(Photosensitivity measurement test)
On the support film of the test piece obtained above, as a negative mask, a density region of 0.00 to 2.00, a density step of 0.05, a tablet size of 20 mm × 187 mm, and a size of each step of 3 mm × 12 mm. Using a DLP exposure machine (product name “DE-1UH” manufactured by Via Mechanics Co., Ltd.) with a phototool having a 41-step step tablet and a 405 nm laser as a light source, with a predetermined amount of energy The photosensitive layer was exposed.
After the development treatment, the photosensitivity of the photosensitive resin composition was evaluated by measuring the number of steps of the step tablet of the photocured film formed on the substrate. The amount of energy (mJ / cm ² ) at which the number of remaining steps after development was 14.0 was determined, and the photosensitivity of the photosensitive resin composition was evaluated. Evaluation "1" what sensitivity is less than ^{30mJ / cm 2, 30J / cm} 2 or more 100 mJ / cm ² the following are "2" and those greater than 100 mJ / cm ² is "3". The lower the photosensitivity, the better.

(Resolution and adhesion measurement test)
As a resolution evaluation pattern, a DLP exposure machine (Via Mechanics Co., Ltd.) using drawing data having a wiring pattern with a line width / space width of n / n (n = 10 to 120 (unit: μm)) as a light source of 405 nm laser The product obtained above was exposed from the support film side using a product name “DE-1UH” manufactured by Co., Ltd. The exposure was performed with an exposure amount at which the number of remaining step steps after development of Hitachi 41-step tablet was 14.0. After the exposure, the same development processing as in the photosensitivity measurement test was performed.
After the current processed image, the space part (unexposed part) is removed neatly, and the line part (exposed part) is the smallest line width / space width value among the resist patterns formed without meandering or chipping. The resolution was evaluated. The smaller this value, the better the resolution.
Adhesion is evaluated based on the line width of the portion where the pattern remains with the smallest line width, using a pattern having a line width: space width ratio of 1: 3 and forming a pattern in the same manner as the resolution evaluation. did. The smaller this value, the better the adhesion.

As is clear from Table 2, the photosensitive elements prepared from the photosensitive resin compositions of Examples 1 to 4 were excellent in resolution and adhesion and excellent in electrostatic characteristics. Moreover, it is thought that the contact angle of water is small and it is excellent also in adhesiveness with a sealing material.
On the other hand, although the photosensitive element produced from the photosensitive resin composition of Comparative Examples 1-2 was excellent in resolution and adhesiveness, an electrostatic characteristic was not different from the past, and the subject remained. The contact angle with water was high, and there was concern about the adhesion of the sealing material.

Claims (9)

(A) component: binder polymer, (B) component: photopolymerizable compound, (C) component: a photosensitive resin composition containing a photopolymerization initiator,
The photosensitive resin composition in which the said binder polymer contains the structural unit derived from the ionic liquid which does not contain a fluorine atom in a molecule | numerator.   (A) component: binder polymer, (B) component: photopolymerizable compound, (C) component: photopolymerization initiator, and (D) component: an ionic liquid containing no fluorine atom in the molecule, Photosensitive resin composition.   The photosensitive resin composition of Claim 1 or 2 whose said ionic liquid is an ionic liquid which has a (meth) acryloyl group in a molecule | numerator. The photosensitive resin composition as described in any one of Claims 1-3 in which the said ionic liquid has a cation of the structure shown by the following general formula (I).

[R ₁ represents an organic group containing a hydrogen atom, a carbon atom, and an oxygen atom. R ₂ represents a hydroxyl group or an organic group containing a (meth) acryloyl group. ]   The photopolymerization initiator contains at least one selected from the group consisting of a hexaarylbiimidazole derivative, an acridine compound, an acetophenone compound, an acylphosphine oxide compound, and an oxime ester compound. The photosensitive resin composition according to item.   The photosensitive resin composition as described in any one of Claims 1-5 whose said binder polymer is a photosensitive polymer which has an at least 1 unsaturated double bond in a molecule | numerator.   (E) component: The photosensitive resin composition as described in any one of Claims 1-6 which further contains a thermosetting agent.   A photosensitive element provided with a support body and the photosensitive layer containing the photosensitive resin composition as described in any one of Claims 1-7 formed on this support body.   A photosensitive layer forming step of laminating a photosensitive layer comprising the photosensitive resin composition according to claim 1 or a photosensitive layer of the photosensitive element according to claim 8 on a substrate, and the photosensitive layer A resist pattern forming method comprising: an exposure step of irradiating a predetermined portion of a layer with actinic rays to form a photocured portion; and a developing step of removing a region other than the predetermined portion of the photosensitive layer from the substrate.