JP2008209880A - Photosensitive resin composition, photosensitive element, resist pattern forming method, and method for manufacturing printed wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new photosensitive resin composition which enables removal of the photosensitive resin composition cured by irradiation with an actinic ray from a substrate in a short period of time, and to improve productivity in the formation of a resist pattern and in the manufacture of a printed wiring board. <P>SOLUTION: The photosensitive resin composition comprises (A) a binder polymer, (B) a photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond within a molecule, and (C) a photopolymerization initiator, wherein the component (B) comprises a compound represented by general formula (1), wherein R<SP>1</SP>denotes a hydrogen atom or a methyl group; R<SP>2</SP>denotes a 1-6C alkylene group; n denotes an integer of 1-30; R<SP>3</SP>and R<SP>4</SP>each independently denote a 1-20C hydrocarbon group, a 1-5C alkoxy group, a halogen atom or a hydroxyl group; p denotes an integer of 0-4; and q denotes an integer of 0-5. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a photosensitive resin composition, a photosensitive element, a resist pattern forming method, and a printed wiring board manufacturing method.

  In the field of manufacturing printed wiring boards, photosensitive resin compositions and photosensitive elements that are laminated on a support and covered with a protective film are widely used as resist materials used for etching or plating.

  The printed wiring board is manufactured by laminating a photosensitive element on a substrate, pattern exposure, removing the unexposed portion of the photosensitive element to form a resist pattern, and etching or plating the substrate on which the resist pattern is formed. The treatment is performed by removing the cured photosensitive resin composition of the exposed portion from the substrate.

  Recently, in order to improve productivity in resist pattern formation and printed wiring board production, it is required to further shorten the process of removing the cured photosensitive resin composition from the substrate, and the cured photosensitivity. Search of the photosensitive resin composition which can remove a resin composition in a short time is performed.

  For example, it contains a photosensitive resin composition (Patent Documents 1 to 4) containing a photopolymerizable compound having a structure capable of shortening the peeling time from the substrate, or a compound having no polymerizable ethylenically unsaturated bond. A photosensitive resin composition (Patent Document 5) has been reported.

Japanese Patent Laid-Open No. 11-133595 Japanese Patent No. 37958872 JP 2005-031647 A JP 2005-134808 A JP 2004-219660 A

  However, the photosensitive resin compositions described in the above Patent Documents 1 to 5 are not substantially shortened in the time required for removing the cured photosensitive resin composition from the substrate. It was not enough to improve. Further, the photosensitive resin composition described in Patent Document 5 has a new problem that the strength of the obtained cured film is lowered.

  Then, this invention aims at providing the new photosensitive resin composition which can remove the photosensitive resin composition hardened | cured by irradiation of actinic light from a board | substrate in a short time. Another object of the present invention is to improve productivity in forming a resist pattern and manufacturing a printed wiring board.

  In order to solve the above problems, the present invention provides (A) a binder polymer, (B) a photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond in the molecule, and (C) photopolymerization. It is the photosensitive resin composition containing an initiator, Comprising: The said (B) component provides the photosensitive resin composition containing the compound represented by following General formula (1).

（式中、Ｒ^１は水素原子又はメチル基を示し、Ｒ^２は炭素数１〜６のアルキレン基を示し、ｎは１〜３０の整数を示す。Ｒ^３及びＲ^４はそれぞれ独立に炭素数１〜２０の炭化水素基、炭素数１〜５のアルコキシ基、ハロゲン原子又は水酸基を示し、ｐは０〜４の整数を示し、ｑは０〜５の整数を示す。）

(In the formula, R ¹ represents a hydrogen atom or a methyl group, R ² represents an alkylene group having 1 to 6 carbon atoms, and n represents an integer of 1 to 30. R ³ and R ⁴ each independently represents the number of carbon atoms. A 1-20 hydrocarbon group, a C1-C5 alkoxy group, a halogen atom, or a hydroxyl group is shown, p shows the integer of 0-4, q shows the integer of 0-5.)

  In the photosensitive resin composition, the exposed portion can be sufficiently photocured by irradiation with actinic rays, but after the resist pattern is formed, the cured photosensitive resin composition can be removed from the substrate in a short time.

  Moreover, this invention provides a photosensitive element provided with a support body and the photosensitive layer containing the said photosensitive resin composition formed on this support body.

  The photosensitive element can sufficiently photo-cure the photosensitive layer in the exposed area by irradiation with actinic rays, but after the resist pattern is formed, the cured photosensitive layer can be removed from the substrate in a short time.

  The present invention also includes a step of laminating the photosensitive element on the substrate so that the photosensitive layer is in close contact with the substrate, a step of irradiating a predetermined portion of the photosensitive layer with an actinic ray and photocuring an exposed portion, And a step of removing the photosensitive layer other than the exposed portion.

  According to the resist pattern forming method, the cured photosensitive layer can be removed from the substrate in a short time, and the productivity in forming the resist pattern can be improved.

  The present invention further includes a step of laminating the photosensitive element on the substrate so that the photosensitive layer is in close contact with the substrate, a step of irradiating a predetermined portion of the photosensitive layer with an actinic ray and photocuring an exposed portion, There is provided a method for producing a printed wiring board, comprising: a step of removing the photosensitive layer other than the exposed portion to form a resist pattern; and a step of etching or plating the substrate on which the resist pattern is formed.

  According to the method for producing a printed wiring board, the cured photosensitive layer can be removed from the substrate in a short time, and the productivity in producing the printed wiring board can be improved.

  If the photosensitive resin composition of the present invention is used, the time required to remove the cured photosensitive layer from the substrate can be shortened. Moreover, if the method for forming a resist pattern or the method for producing a printed wiring board of the present invention is used, the productivity in forming the resist pattern and manufacturing the printed wiring board can be improved.

  Hereinafter, the best mode for carrying out the invention will be described in detail. In the present invention, (meth) acrylic acid means acrylic acid and methacrylic acid corresponding to it, (meth) acrylate means acrylate and methacrylate corresponding to it, and (meth) acryloyl group means An acryloyl group and its corresponding methacryloyl group are meant.

  The photosensitive resin composition of the present invention comprises (A) a binder polymer, (B) a photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond in the molecule, and (C) photopolymerization initiation. A photosensitive resin composition containing the agent, wherein the component (B) contains a compound represented by the general formula (1).

  Examples of the binder polymer of the component (A) include acrylic resins, styrene resins, epoxy resins, amide resins, amide epoxy resins, alkyd resins, and phenol resins. From the viewpoint of alkali developability, an acrylic resin is preferable. These can be used alone or in combination of two or more.

  The binder polymer can be produced, for example, by radical polymerization of a polymerizable monomer. Examples of the polymerizable monomer include polymerizable styrene derivatives substituted at the α-position or aromatic ring such as styrene, vinyl toluene, α-methylstyrene, acrylamide such as diacetone acrylamide, acrylonitrile, vinyl- Esters of vinyl alcohol such as n-butyl ether, (meth) acrylic acid alkyl ester, (meth) acrylic acid tetrahydrofurfuryl ester, (meth) acrylic acid dimethylaminoethyl ester, (meth) acrylic acid diethylaminoethyl ester, (meta ) Acrylic acid glycidyl ester, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, (meth) acrylic acid, α-bromo (meth) acrylic acid , Α-Chlor (meta Acrylic acid, 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 and the like.

（式中、Ｒ^３は水素原子又はメチル基を示し、Ｒ^４は炭素数１〜１２のアルキル基を示す。）で表される化合物、これらの化合物のアルキル基に水酸基、エポキシ基、ハロゲン基等が置換した化合物等が挙げられる。 As the (meth) acrylic acid alkyl ester, for example, the following general formula (2)

(Wherein R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents an alkyl group having 1 to 12 carbon atoms), the alkyl group of these compounds is a hydroxyl group, an epoxy group, or a halogen group. And the like are substituted.

Examples of the alkyl group having 1 to 12 carbon atoms represented by R ⁴ in the general formula (2) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and a nonyl group. Group, decyl group, undecyl group, dodecyl group and structural isomers thereof.

  As a monomer of the compound represented by the general formula (2), for example, (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 decyl ester, (meth) acrylic acid undecyl ester, (meth) acrylic acid dodecyl ester, and the like. These can be used alone or in combination of two or more.

  The binder polymer preferably contains a carboxyl group from the viewpoint of alkali developability. For example, the binder polymer can be produced by radical polymerization of a polymerizable monomer having a carboxyl group and another polymerizable monomer. it can. As the polymerizable monomer having a carboxyl group, methacrylic acid is preferable.

  The binder polymer preferably contains styrene or a styrene derivative as a polymerizable monomer from the viewpoint of flexibility.

  In order to improve both adhesiveness and peeling properties using styrene or a styrene derivative as a copolymerization component, it is preferable to include 0.1 to 30% by mass, more preferably 1 to 28% by mass. It is especially preferable to contain 5-27 mass%. If this content is less than 0.1% by mass, the adhesion tends to be inferior, and if it exceeds 30% by mass, the peel piece tends to be large and the peel time tends to be long.

  The above binder polymers can be used alone or in combination of two or more. As a binder polymer in the case of using two or more types in combination, for example, two or more types of binder polymers composed of different copolymerization components, two or more types of binder polymers having different mass average molecular weights, two or more types of binder polymers having different dispersities Examples include binder polymers, and examples thereof include acrylic resins, styrene resins, epoxy resins, amide resins, amide epoxy resins, alkyd resins, and phenol resins. From the viewpoint of alkali developability, an acrylic resin is preferable.

  The carboxyl group content (ratio of the polymerizable monomer having a carboxyl group to the total polymerizable monomer used) of the binder polymer of the component (A) is 12 from the viewpoint of the balance between alkali developability and alkali resistance. It is preferably -50% by mass, more preferably 12-40% by mass, particularly preferably 15-30% by mass, and particularly preferably 15-25% by mass. When the carboxyl group content is less than 12% by mass, the alkali developability tends to be inferior, and when it exceeds 50% by mass, the alkali resistance tends to be inferior.

  The weight average molecular weight of the binder polymer is preferably 20,000 to 300,000, more preferably 40,000 to 150,000, from the viewpoint of the balance between mechanical strength and alkali developability. When the mass average molecular weight is less than 20,000, the developer resistance tends to decrease, and when it exceeds 300,000, the development time tends to be long. The mass average molecular weight in the present invention is a value measured by a gel permeation chromatography method and converted by a calibration curve prepared using standard polystyrene.

Examples of the alkylene group having 1 to 6 carbon atoms of R ^{2 in} the compound represented by the general formula (1) included as an essential component in the photopolymerizable compound of the component (B) include, for example, a methylene group, an ethylene group, A propylene group, an isopropylene group, a butylene group, an isobutylene group, a pentylene group, a neopentylene group, a hexylene group, and the like are exemplified, and an ethylene group is preferable.

The isopropylene group is a group represented by —CH (CH ₃ ) CH ₂ —, and the bonding direction of — (R ² —O) — in the compound represented by the general formula (1) is a methylene group. May be bonded to oxygen and the methylene group may not be bonded to oxygen. However, the bonding direction may be one or two bonding directions may be mixed.

In addition, when each of the repeating units of — (R ² —O) — is 2 or more, the two or more R ^{2 s} may be the same or different, and R ² is different and two or more of them are different. In the case where it is composed of an alkylene group, two or more kinds of — (R ² —O) — may be present at random or may be present as a block.

In the compound represented by the general formula (1), n is an integer of 1 to 30, preferably 1 to 20, more preferably 1 to 10, more preferably 1 to 5 from the viewpoint of peelability. It is particularly preferred that Examples of the compound represented by the general formula (1) that can be obtained include CMP-3A (trade name, manufactured by Hitachi Chemical Co., Ltd.) in which R ¹ is a hydrogen atom, R ² is an ethylene group, and n = 3. Is mentioned. These can be used alone or in combination of two or more.

  Examples of the photopolymerizable compound of the component (B) other than the compound represented by the general formula (1) include a compound obtained by reacting a polyhydric alcohol with an α, β-unsaturated carboxylic acid, 2, 2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxypolypropoxy) phenyl) propane, 2,2-bis (4-(( (Meth) acryloxypolyethoxypolypropoxy) phenyl) propane-based bisphenol A-based (meth) acrylate compounds, compounds obtained by reacting glycidyl group-containing compounds with α, β-unsaturated carboxylic acids, having urethane bonds (meta ) Urethane monomers such as acrylate compounds, γ-chloro-β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthale , Β-hydroxyethyl-β ′-(meth) acryloyloxyethyl-o-phthalate, β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate, (meth) acrylic acid alkyl ester, etc. However, it is preferable to use a bisphenol A-based (meth) acrylate compound or a (meth) acrylate compound having a urethane bond as an essential component. These can be used alone or in combination of two or more.

  Examples of 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane include 2,2-bis (4-((meth) acryloxydiethoxy) phenyl) propane, 2,2- Bis (4-((meth) acryloxytriethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxytetraethoxy) phenyl) propane, 2,2-bis (4-((meth)) Acryloxypentaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyhexaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyheptaethoxy) phenyl) propane 2,2-bis (4-((meth) acryloxyoctaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxy nonaethoxy) ) Phenyl) propane, 2,2-bis (4-((meth) acryloxydecaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyundecaethoxy) phenyl) propane, 2, 2-bis (4-((meth) acryloxydodecaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxytridecaethoxy) phenyl) propane, 2,2-bis (4- ( (Meth) acryloxytetradecaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxypentadecaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyhexa) Decaethoxy) phenyl) propane and the like, and 2,2-bis (4- (methacryloxypentaethoxy) phenyl) propane is BPE-50. (Product name) manufactured by Shin-Nakamura Chemical Co., Ltd. is commercially available, and 2,2-bis (4- (methacryloxypentadecaethoxy) phenyl) propane is BPE-1300 (Shin-Nakamura Chemical Industry). It is commercially available as a product name. These can be used alone or in combination of two or more.

  Examples of 2,2-bis (4-((meth) acryloxypolypropoxy) phenyl) propane include 2,2-bis (4-((meth) acryloxydipropoxy) phenyl) propane, 2,2- Bis (4-((meth) acryloxytripropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxytetrapropoxy) phenyl) propane, 2,2-bis (4-((meth)) Acryloxypentapropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyhexapropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyheptapropoxy) phenyl) propane 2,2-bis (4-((meth) acryloxyoctapropoxy) phenyl) propane, 2,2-bis (4-((meth) acrylic) Xinonapropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxydecapropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyundecapropoxy) phenyl) propane 2,2-bis (4-((meth) acryloxydodecapropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxytridecapropoxy) phenyl) propane, 2,2-bis ( 4-((meth) acryloxytetradecapropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxypentadecapropoxy) phenyl) propane, 2,2-bis (4-((meth)) And acryloxyhexadecapropoxy) phenyl) propane. These can be used alone or in combination of two or more.

  Examples of 2,2-bis (4-((meth) acryloxypolyethoxypolypropoxy) phenyl) propane include 2,2-bis (4-((meth) acryloxydiethoxyoctapropoxy) phenyl) propane, Examples include 2,2-bis (4-((meth) acryloxytetraethoxytetrapropoxy) phenyl) propane and 2,2-bis (4-((meth) acryloxyhexaethoxyhexapropoxy) phenyl) propane. These can be used alone or in combination of two or more.

  Examples of the compound obtained by reacting a polyhydric alcohol with an α, β-unsaturated carboxylic acid include, for example, polyethylene glycol di (meth) acrylate having 2 to 14 ethylene groups and 2 to 14 propylene groups. Polypropylene glycol di (meth) acrylate, having 2 to 14 ethylene groups and 2 to 14 propylene groups, polypropylene polypropylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, tri Methylolpropane tri (meth) acrylate, trimethylolpropane ethoxytri (meth) acrylate, trimethylolpropane diethoxytri (meth) acrylate, trimethylolpropane triethoxytri (meth) acrylate, trimethylolpropane tetraethoxy Tri (meth) acrylate, trimethylolpropane pentaethoxytri (meth) acrylate, tetramethylolmethane tri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, polypropylene glycol di (meta) having 2 to 14 propylene groups ) Acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and the like.

  Examples of the urethane monomer include a (meth) acryl monomer having an OH group at the β-position and a diisocyanate compound such as isophorone diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate, and 1,6-hexamethylene diisocyanate. Addition reaction product, tris ((meth) acryloxytetraethylene glycol isocyanate) hexamethylene isocyanurate, EO-modified urethane di (meth) acrylate, EO, PO-modified urethane di (meth) acrylate, and the like. Note that EO represents ethylene oxide, and the EO-modified compound has a block structure of an ethylene oxide group.

  PO represents propylene oxide, and the PO-modified compound has a block structure of propylene oxide groups. Examples of the EO-modified urethane di (meth) acrylate include UA-11 (manufactured by Shin-Nakamura Chemical Co., Ltd.).

  Examples of EO and PO-modified urethane di (meth) acrylate include UA-13 (manufactured by Shin-Nakamura Chemical Co., Ltd.).

  Examples of the photopolymerization initiator of the component (C) include benzophenone, N, N′-tetramethyl-4,4′-diaminobenzophenone (Michler ketone), N, N′-tetraethyl-4,4′-diaminobenzophenone. 4-methoxy-4′-dimethylaminobenzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-methyl-1- [4- (methylthio) phenyl] -2 -Aromatic ketones such as morpholino-propanone-1, 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chromo Anthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenantharaquinone, quinones such as 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, benzoin methyl ether, benzoin ethyl ether, benzoin Benzoin ether compounds such as phenyl ether, benzoin compounds such as benzoin, methylbenzoin and ethylbenzoin, benzyl derivatives such as benzyldimethyl ketal, 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o -Chlorophenyl) -4,5-di (methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5- Diphenylimidazole , 2,4,5-triarylimidazole dimer such as 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, 9-phenylacridine, 1,7-bis (9,9 ′ -Acridinyl) heptane and other acridine derivatives, N-phenylglycine, N-phenylglycine derivatives, coumarin compounds, oxazole compounds and the like.

  The aryl group substituents of two 2,4,5-triarylimidazoles may give the same and interesting compounds, or differently give asymmetric compounds. Moreover, you may combine a thioxanthone type compound and a tertiary amine compound like the combination of diethyl thioxanthone and dimethylaminobenzoic acid. From the viewpoint of adhesion and sensitivity, 2,4,5-triarylimidazole dimer is more preferable. These can be used alone or in combination of two or more.

  The blending amount of the binder polymer of the component (A) is preferably 30 to 80 parts by mass, and 50 to 70 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B). More preferably. If the blending amount is less than 40 parts by mass, the photocured product tends to be brittle, and when used as a photosensitive element, the coating property tends to be inferior. There is a tendency to become brittle.

  The blending amount of the photopolymerizable compound of the component (B) is preferably 20 to 60 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B), and 30 to 55 parts. It is more preferable to set it as a mass part. If the blending amount is less than 20 parts by mass, the photosensitivity tends to be insufficient, and if it exceeds 60 parts by mass, the photocured product becomes brittle, and when used as a photosensitive element, the coating property tends to be inferior.

  The blending amount of the photopolymerization initiator of the component (C) is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B). More preferably, it is 2 to 5 parts by mass. If the blending amount is less than 0.01 parts by weight, the photosensitivity tends to be insufficient, and if it exceeds 20 parts by weight, the absorption at the surface of the composition increases during exposure and the internal photocuring is insufficient. Tend to be.

  The photosensitive resin composition may include a dye such as malachite green, a photochromic agent such as tribromophenylsulfone or leuco crystal violet, a thermochromic inhibitor, a plasticizer such as p-toluenesulfonamide, or a pigment, if necessary. , Fillers, antifoaming agents, flame retardants, stabilizers, adhesion-imparting agents, leveling agents, peeling accelerators, antioxidants, fragrances, imaging agents, thermal crosslinking agents, and the like (A) and (B ) About 0.01 to 20 parts by mass per 100 parts by mass of the total component. These can be used alone or in combination of two or more.

  The photosensitive resin composition is dissolved in a solvent such as methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N-dimethylformamide, propylene glycol monomethyl ether, or a mixed solvent thereof, if necessary. And it can apply | coat as a solution of about 30-60 mass% of solid content.

  The photosensitive resin composition is a liquid resist on a metal surface, for example, a surface of an iron-based alloy such as copper, a copper-based alloy, nickel, chromium, iron, or stainless steel, preferably copper, a copper-based alloy, or an iron-based alloy. After being applied and dried, it is preferably used by coating with a protective film, if necessary, or in the form of a photosensitive element.

  Moreover, the photosensitive element of this invention is equipped with a support body and the photosensitive layer containing the said photosensitive resin composition formed on this support body, It is characterized by the above-mentioned.

  FIG. 1 is a schematic cross-sectional view showing a preferred embodiment of a photosensitive element. The photosensitive element 1 shown in FIG. 1 has a structure in which a photosensitive layer 14 is laminated on a support 10. The photosensitive layer 14 is a layer containing a photosensitive resin composition.

  As the support 10, for example, a metal plate such as copper, a copper-based alloy, iron, or an iron-based alloy, or a polymer film such as polyethylene terephthalate, polypropylene, polyethylene, or polyester can be used. From the viewpoint of transparency, it is preferable to use a polyethylene terephthalate film. Moreover, it is preferable that the thickness of the support body 10 is 1-100 micrometers.

  The photosensitive layer 14 can be formed by applying the photosensitive resin composition as a liquid resist on the support 10.

  Although the thickness of the photosensitive layer 14 changes with uses, it is preferable that it is 1-200 micrometers in thickness after drying, and it is more preferable that it is 1-100 micrometers. If the thickness is less than 1 μm, it tends to be difficult to apply industrially, and if it exceeds 200 μm, the effect of the present invention is small, the sensitivity is insufficient, and the photocurability at the bottom of the resist tends to deteriorate.

  When the photosensitive resin composition is applied onto the support 10, if necessary, a coating solution prepared by dissolving the photosensitive resin composition in a predetermined solvent to obtain a solution having a solid content of 30 to 60% by mass. It may be used as Examples of such solvents include methanol, ethanol, propanol, ethylene glycol, propylene glycol, octane, decane, petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, solvent naphtha, acetone, methyl isobutyl ketone, methyl ethyl ketone, cyclohexanone, toluene, xylene. , Tetramethylbenzene, N, N-dimethylformamide, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether, propylene Glycol mono Chill ether, dipropylene glycol diethyl ether, triethylene glycol monoethyl ether, ethyl acetate, butyl acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate , Organic solvents such as dipropylene glycol monomethyl ether acetate, or a mixed solvent thereof.

  Examples of the coating method include a roll coater, a comma coater, a gravure coater, an air knife coater, a die coater, and a bar coater. The solvent can be removed, for example, by heating. In this case, the heating temperature is preferably about 70 to 150 ° C., and the heating time is preferably about 5 to about 30 minutes.

  The amount of the remaining organic solvent in the photosensitive layer 14 thus formed is preferably 2% by mass or less from the viewpoint of preventing the diffusion of the organic solvent in the subsequent step.

  Examples of the protective film include polymer films such as polyethylene and polypropylene. Further, the protective film is preferably a low fish eye film, and the adhesive force between the protective film and the photosensitive layer 14 is such that the protective film 14 and the support 10 are separated in order to easily peel the protective film from the photosensitive layer 14. It is preferable that it is smaller than the adhesive force between.

  Since the polymer film must be removable from the photosensitive layer 14 later, the polymer film has been subjected to a surface treatment that makes removal impossible, or a material that makes removal impossible. should not be done. The thickness of the polymer film is preferably 1 to 100 μm, and more preferably 1 to 30 μm. If this thickness is less than 1 μm, the mechanical strength tends to decrease and the polymer film tends to be broken at the time of coating. If it exceeds 30 μm, the resolution tends to decrease and the price tends to increase. There is.

  One of the polymer films may be laminated on both sides of the photosensitive layer 14 with one of them as a support film for the photosensitive layer 14 and the other as a protective film for the photosensitive resin composition. The protective film preferably has a smaller adhesive strength between the photosensitive layer 14 and the protective film than the adhesive strength between the photosensitive layer 14 and the support 10, and is preferably a low fisheye film.

  The photosensitive element 1 has an intermediate layer such as a cushion layer, an adhesive layer, a light absorption layer, a gas barrier layer, or a protective layer between the support 10 and the photosensitive layer 14 and / or between the photosensitive layer 14 and the protective film. A layer may be further provided.

  The photosensitive element 1 is, for example, in the form of a flat plate as it is or by laminating a protective film on one surface of the photosensitive layer 14 (on the surface that is not protected and exposed) to form a cylindrical core or the like. It can be wound and stored in roll form. The core is not particularly limited as long as it is conventionally used. For example, polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, ABS resin (acrylonitrile-butadiene-styrene copolymer), etc. Examples include plastics. At the time of storage, it is preferable to wind up so that the support body 10 may become the outermost side. Moreover, it is preferable to install an end face separator from the viewpoint of protecting the end face on the end face of the photosensitive element 1 (photosensitive element roll) wound in a roll shape. In addition, a moisture-proof end face separator is used from the viewpoint of edge fusion resistance. It is preferable to install. Moreover, when packaging the photosensitive element 1, it is preferable to wrap it in a black sheet with low moisture permeability.

  The resist pattern forming method of the present invention includes a step of laminating the photosensitive element on the substrate so that the photosensitive layer is in close contact with the substrate, and exposing a predetermined portion of the photosensitive layer by irradiating actinic rays. A step of photocuring a portion and a step of removing the photosensitive layer other than the exposed portion.

  When forming a resist pattern using the photosensitive element 1, if a protective film is present, after removing the protective film, the photosensitive layer 14 containing the photosensitive resin composition is heated on the circuit forming substrate. The method of laminating | stacking by crimping is mentioned, It is preferable to laminate | stack under reduced pressure from the viewpoint of adhesiveness and followable | trackability.

The surface to be laminated is usually a metal surface, but is not particularly limited. The heating temperature of the photosensitive layer 14 is preferably 70 to 130 ° C., and the pressing pressure is preferably about 0.1 to 1.0 MPa (about 1 to 10 kgf / cm ² ). There is no limit.

  Further, if the photosensitive layer 14 is heated to 70 to 130 ° C. as described above, it is not necessary to pre-heat the circuit forming substrate in advance. However, in order to further improve the stackability, the circuit forming substrate is preliminarily processed. Heat treatment can also be performed.

  The photosensitive layer 14 thus laminated is irradiated with actinic rays in an image form through a negative or positive mask pattern called an artwork. At this time, if the polymer film present on the photosensitive layer 14 is transparent, it may be irradiated with actinic rays as it is, but if it is opaque, it needs to be removed.

  As the light source of actinic light, a known light source such as a carbon arc lamp, a mercury vapor arc lamp, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, or a xenon lamp that emits ultraviolet rays effectively is used. Moreover, what emits visible light effectively, such as a photographic flood light bulb and a solar lamp, is also used.

  Next, after the exposure, when the support 10 is present on the photosensitive layer 14, the support 10 is removed, and then the unexposed portion is removed and developed by wet development, dry development or the like, and a resist pattern is formed. Form.

  In the case of wet development, development is performed by a known method such as spraying, rocking immersion, brushing, scraping, or the like, using a developer corresponding to the photosensitive resin composition such as an alkaline aqueous solution, an aqueous developer, or an organic solvent. To do. As the developing solution, a safe and stable solution having good operability such as an alkaline aqueous solution is used.

  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 Alkali metal phosphates such as alkali metal pyrophosphates such as sodium pyrophosphate and potassium pyrophosphate are used.

  Examples of the alkaline aqueous solution used for development include a dilute solution of 0.1 to 5% by mass of sodium carbonate, a dilute solution of 0.1 to 5% by mass of potassium carbonate, a dilute solution of 0.1 to 5% by mass of sodium hydroxide, A dilute solution of 1 to 5 mass% sodium tetraborate is preferred.

  The pH of the alkaline aqueous solution used for development is preferably in the range of 9 to 11, and the temperature is adjusted according to the developability of the photosensitive layer 14. Further, in the alkaline aqueous solution, a surfactant, an antifoaming agent, a small amount of an organic solvent for accelerating development, and the like may be mixed.

  The aqueous developer comprises water or an alkaline aqueous solution and one or more organic solvents. Examples of the alkaline substance include borax, sodium metasilicate, tetramethylammonium hydroxide, ethanolamine, ethylenediamine, diethylenetriamine, 2-amino-2-hydroxymethyl-1,3-propanediol, , 3-diaminopropanol-2, morpholine and the like. The pH of the developer is preferably as low as possible within a range where the resist can be sufficiently developed, preferably pH 8-12, and more preferably pH 9-10.

  Examples of the organic solvent include 3 acetone alcohol, 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, diethylene glycol monobutyl ether. Etc. These can be used alone or in combination of two or more.

  The concentration of the organic solvent is usually preferably 2 to 90% by mass, and the temperature can be adjusted according to the developability. Further, a small amount of a surfactant, an antifoaming agent and the like can be mixed in the aqueous developer.

  Examples of the organic solvent-based developer used alone include 1,1,1-trichloroethane, N-methylpyrrolidone, N, N-dimethylformamide, cyclohexanone, methyl isobutyl ketone, and γ-butyrolactone. These organic solvents preferably add water in the range of 1 to 20% by mass in order to prevent ignition. Moreover, you may use together 2 or more types of image development methods as needed.

Development methods include a dip method, a battle method, a spray method, brushing, and slapping, and the high pressure spray method is most suitable for improving the resolution. As the treatment after development, the resist pattern may be further cured and used by performing heating at about 60 to 250 ° C. or exposure at about 0.2 to 10 mJ / cm ² as necessary.

  For etching the metal surface after development, a cupric chloride solution, a ferric chloride solution, an alkaline etching solution, or a hydrogen peroxide-based etching solution can be used, but ferric chloride is used because of its good etch factor. It is desirable to use a solution.

  The printed wiring board manufacturing method of the present invention includes a step of laminating the photosensitive element on the substrate so that the photosensitive layer is in close contact with the substrate, and irradiating a predetermined portion of the photosensitive layer with actinic rays. The method includes a step of photocuring an exposed portion, a step of removing a photosensitive layer other than the exposed portion to form a resist pattern, and a step of etching or plating the substrate on which the resist pattern has been formed. Yes.

  When a printed wiring board is manufactured using the photosensitive element 1, the surface of the circuit forming substrate is treated by a known method such as etching or plating using the developed resist pattern as a mask.

  Examples of plating methods include copper plating such as copper sulfate plating and copper pyrophosphate plating, solder plating such as high-throw solder plating, nickel plating such as watt bath (nickel sulfate-nickel chloride) plating, nickel sulfamate plating, and hard gold. Examples thereof include gold plating such as plating and soft gold plating.

  Next, the resist pattern can be peeled 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 a dipping method and a spray method, and the dipping method and the spray method may be used alone or in combination. The printed wiring board on which the resist pattern is formed may be a multilayer printed wiring board or may have a small diameter through hole.

Hereinafter, the present invention will be described with reference to examples.
(Preparation of component (A))
To a flask equipped with a stirrer, reflux condenser, thermometer, dropping funnel and nitrogen gas inlet tube, 400 g of a mixture of methyl cellosolve and toluene having a mass ratio of 6: 4 was added, and stirred while blowing nitrogen gas. And heated to 80 ° C.

  Subsequently, a solution prepared by mixing 100 g of methacrylic acid, 250 g of methyl methacrylate, 100 g of ethyl acrylate, 50 g of styrene, and 0.8 g of azobisisobutyronitrile was dropped into the flask over 4 hours, and then at 80 ° C. for 2 hours. Keep warm while stirring.

  Further, a solution prepared by adding 1.2 g of azobisisobutyronitrile to 100 g of a mixture of methyl cellosolve and toluene having a mass ratio of 6: 4 was dropped into the flask over 10 minutes, and then at 80 ° C. The mixture was kept warm for 3 hours and then heated to 90 ° C. over 30 minutes.

  Then, the obtained solution was cooled, acetone was added so that a non-volatile component (solid content) might be 50 mass%, and the solution of the binder polymer used as (A) component was obtained. The weight average molecular weight of the binder polymer was 80,000. The mass average molecular weight was measured by gel permeation chromatography (GPC) method, and was derived by conversion using a standard polystyrene calibration curve.

The GPC conditions are as shown below.
・ Pump: Hitachi L-6000 type [manufactured by Hitachi, Ltd.]
Column: Gelpack GL-R420 + Gelpack GL-R430 +
・ Gelpack GL-R440 (three in total) [above, manufactured by Hitachi Chemical Co., Ltd.]
・ Eluent: Tetrahydrofuran ・ Measurement temperature: 25 ° C.
-Flow rate: 2.05 mL / min-Detector: Hitachi L-3300 type RI [manufactured by Hitachi, Ltd.]

５）ＦＡ−ＭＥＣＨ：γ−クロロ−β−ヒドロキシプロピル−β’−メタクリロイルオキシエチル-o-フタレート（日立化成工業（株）製）
６）ＵＡ−１１：ポリエチレングリコール変性ウレタンジ（メタ）アクリレート（新中村化学工業（株）製）
７）ＢＰＥ−５００：２，２−ビス（４−（メタクリロキシペンタデカエトキシ）フェニル）（新中村化学工業（株）製）
８）ＡＰＧ−４００：ポリプロピレングリコール＃４００ジアクリレート（新中村化学工業（株）製） ((B) component)
The photopolymerizable compound used as the component (B) is as follows.
1) CMP-1A: Compound represented by the following general formula (1): R ¹ is a hydrogen atom, R ² is an ethylene group, n = 1, p = 0, q = 0 (Hitachi Chemical Industry Co., Ltd.) ) Made)
2) CMP-3A: a compound represented by the following general formula (1), wherein R ¹ is a hydrogen atom, R ² is an ethylene group, n = 3, p = 0, q = 0 (Hitachi Chemical Industry Co., Ltd.) ) Made)
3) CMP-6A: Compound represented by the following general formula (1): R ¹ is a hydrogen atom, R ² is an ethylene group, n = 6, p = 0, q = 0 compound (Hitachi Chemical Co., Ltd.) ) Made)
4) CMP-3M: Compound represented by the following general formula (1): R ¹ is a methyl group, R ² is an ethylene group, n = 3, p = 0, q = 0 (Hitachi Chemical Industry Co., Ltd.) ) Made)

5) FA-MECH: γ-chloro-β-hydroxypropyl-β′-methacryloyloxyethyl-o-phthalate (manufactured by Hitachi Chemical Co., Ltd.)
6) UA-11: Polyethylene glycol-modified urethane di (meth) acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)
7) BPE-500: 2,2-bis (4- (methacryloxypentadecaethoxy) phenyl) (manufactured by Shin-Nakamura Chemical Co., Ltd.)
8) APG-400: Polypropylene glycol # 400 diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)

((C) component)
As the photopolymerization initiator of component (C), 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer and N, N′-tetraethyl-4,4′-diaminobenzophenone were used.

(Other ingredients)
Malachite green and leuco crystal violet were used as additives. As the solvent, acetone, toluene and methanol were used.

(Production of photosensitive resin composition)
In the blending amounts shown in Table 1 and Table 2, the (A) component, the (B) component, the (C) component, the additive and the solvent are blended, and the photosensitive properties of Examples 1 to 4 and Comparative Examples 1 to 3, respectively. A solution of the resin composition was obtained.

(Manufacture of photosensitive elements)
The above-mentioned photosensitive resin composition solution was uniformly applied onto a 16 μm thick polyethylene terephthalate film (trade name G2-16, manufactured by Teijin Limited), and dried for 10 minutes with a hot air convection dryer at 100 ° C. Then, it protected with the protective film made from polyethylene (Tamapoly Co., Ltd. brand name: NF-13). The film thickness of each photosensitive layer was 40 μm.

  It is a glass epoxy material in which copper foil (thickness 35 μmm) is laminated on both sides, and its surface is polished by a polishing machine (manufactured by Sankei Co., Ltd.) having a brush equivalent to # 600, washed with water and dried with an air flow. A copper-clad laminate (trade name: MCL-E-61, manufactured by Hitachi Chemical Co., Ltd.) is heated to 80 ° C. and made of the above polyethylene at a rate of 1.5 m / min using a 110 ° C. heat roll. While peeling off the protective film, the photosensitive layer was laminated on the surface of the copper clad laminate. In this way, the photosensitive element containing the photosensitive resin composition of Examples 1-4 or Comparative Examples 1-3 was manufactured. FIG. 1 is a schematic cross-sectional view showing a preferred embodiment of a photosensitive element.

(Formation of resist pattern)
As a negative, a Hitachi 41-step tablet was placed on the photosensitive element and exposed at 60 mJ / cm ² using an exposure machine (trade name HMW-201GX, manufactured by Oak Co., Ltd.) having a high-pressure mercury lamp lamp.

  Thereafter, the polyethylene terephthalate film was peeled off from each photosensitive element, and an unexposed portion was removed by spraying a 1.0% by mass aqueous sodium carbonate solution at 30 ° C. for 60 seconds to form a resist pattern.

(Evaluation of photosensitive resin composition)
1) Photosensitivity 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 copper-clad laminate of the photosensitive element. The photosensitivity is indicated by the number of steps of the step tablet, and the higher the number of steps of the step tablet, the higher the photosensitivity.

2) Adhesion Wiring with a line width / space width of 30/400 to 200/400 (unit: μm) as a phototool having a copper-clad laminate of photosensitive elements, a Hitachi 41-step tablet, and an adhesive evaluation negative A photo tool having a pattern is brought into close contact, and exposure is performed with an energy amount that the remaining number of steps after development of Hitachi 41-step tablet is 23.0, and the smallest line width value of the exposed portion after 60 seconds of development processing is measured. By doing so, the adhesiveness of the photosensitive resin composition was evaluated. The adhesion is indicated by the value of the line width, and the smaller the value, the better.

3) Resolution A copper-clad laminate of photosensitive elements, a photo tool having a Hitachi 41-step tablet, and a wiring pattern with a line width / space width of 400/30 to 400/200 (unit: μm) as a negative for resolution evaluation. A line width that allows the unexposed area to be removed cleanly after 60 seconds of development processing, with a photo tool that is in close contact, exposed with an energy amount of 23.0 steps after development of a Hitachi 41-step tablet. The resolution of the photosensitive resin composition was evaluated by measuring the smallest value of the space width between them. The resolution is indicated by the value of the space width, and the smaller the value, the better.

4) Peeling time The copper-clad laminate of the photosensitive element, a phototool having a Hitachi 41-step step tablet, and a phototool having a vertical / horizontal of 60/45 (unit: mm) as a negative for peeling time measurement, The evaluation substrate obtained by exposing the Hitachi 41-step tablet with an energy amount that the remaining step step after development is 23.0, developing the substrate for 60 seconds, and removing the unexposed portion is stirred with a stirrer. The immersion time of the photosensitive resin composition was evaluated by immersing it in an aqueous solution of sodium hydroxide at 50 ° C. and 3% (wt / wt) and measuring the time required for the exposed part to be peeled from the copper-clad laminate. did. It can be evaluated that the peeling time is better as the time is shorter.

5) Evaluation results Table 3 shows the results of examining the photosensitivity, adhesion, resolution, and peeling time of the photosensitive resin compositions of Examples 1 to 4 or Comparative Examples 1 to 3.

  As a result, it was revealed that the photosensitive resin compositions of Examples 1 to 4 were significantly shorter in peeling time than the photosensitive resin compositions of Comparative Examples 1 to 3. Therefore, if the photosensitive resin compositions of Examples 1 to 4 are used, the production efficiency in the peeling process can be sufficiently improved, and the productivity in the formation of resist patterns and the production of printed wiring boards can be greatly improved. Was suggested.

It is a schematic cross section which shows suitable one Embodiment of a photosensitive element.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Photosensitive element, 10 ... Support body, 14 ... Photosensitive layer, F1 ... Surface on the opposite side to support body side

Claims (4)

(A) a binder polymer;
(B) a photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond in the molecule;
(C) a photopolymerization initiator;
A photosensitive resin composition comprising:
The component (B) contains a compound represented by the following general formula (1).
Photosensitive resin composition.

(In the formula, R ¹ represents a hydrogen atom or a methyl group, R ² represents an alkylene group having 1 to 6 carbon atoms, and n represents an integer of 1 to 30. R ³ and R ⁴ each independently represents the number of carbon atoms. A 1-20 hydrocarbon group, a C1-C5 alkoxy group, a halogen atom, or a hydroxyl group is shown, p shows the integer of 0-4, q shows the integer of 0-5.)   A photosensitive element comprising: a support; and a photosensitive layer comprising the photosensitive resin composition according to claim 1 formed on the support. Laminating the photosensitive element according to claim 2 on the substrate such that the photosensitive layer is in close contact with the substrate;
Irradiating a predetermined portion of the photosensitive layer with actinic rays to photocure the exposed portion;
Removing the photosensitive layer other than the exposed portion;
A method for forming a resist pattern. Laminating the photosensitive element according to claim 2 on the substrate such that the photosensitive layer is in close contact with the substrate;
Irradiating a predetermined portion of the photosensitive layer with an actinic ray to photocuring an exposed portion;
Removing the photosensitive layer other than the exposed portion to form a resist pattern;
Etching or plating the substrate on which a resist pattern is formed; and
A method for manufacturing a printed wiring board, comprising:

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