JP2005221739A - Photosensitive resin composition, photosensitive element obtained by using same, method for producing photoresist pattern and method for producing printed wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive resin composition useful for densification and a higher yield of a printed wiring board produced using laser exposure; a photosensitive element obtained by using the same; a method for producing a photoresist pattern; and a method for producing a printed wiring board. <P>SOLUTION: The photosensitive resin composition contains a binder polymer, a photopolymerizable compound having an ethylenically unsaturated group, and a hexaarylbisimidazole compound and a hydrogen donor as a photopolymerization initiator, and has the following properties (a)-(c); (a) an absorbance of a photosensitive resin composition layer to monochromatic light within the range of 340-410 nm is 0.2-0.8, (b) an aspect ratio of a pattern of a photoresist produced by developing the photosensitive resin composition layer formed on a substrate after exposure with monochromatic light is ≥0.7, (c) when the photosensitive resin composition layer is formed on a substrate having 24 holes of 6 mm diameter, the layer is exposed in such a way that the number of residual steps after a prescribed development becomes 20, and development is carried out 3 times, a hole-break ratio is ≤10%. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a photosensitive resin composition, a photosensitive element using the same, a method for producing a photoresist pattern, and a method for producing a printed wiring board.

  Conventionally, as a method for forming an electric circuit (wiring pattern) on a printed wiring board, a tenting method and a plating method are known. This tenting method is a method in which a copper through hole for chip mounting is protected with a photoresist, and an electric circuit is formed through etching and photoresist stripping. The plating method is a method in which copper is deposited in a through hole by electroplating, protected by solder plating, and an electric circuit is formed by removing a photoresist and etching.

  With the recent increase in the density of printed wiring boards, photosensitive elements are increasingly demanded for high resolution and high adhesion as compared to conventional photosensitive elements. At the same time, there is a growing demand for higher photosensitivity in terms of throughput.

  On the other hand, with the rapid generation change of electronic devices such as mobile phones, there is a concern that the cost of a mask for a single substrate increases in a conventional method of forming a photoresist pattern using a phototool (photomask). ing. Therefore, a method of directly drawing a circuit created by CAD without using a mask with laser light using monochromatic light as a light source (Laser Direct Imaging, hereinafter referred to as LDI) has been reviewed. As mentioned above, LDI can efficiently produce a small variety of products, and since it does not use a photomask, the alignment process can be omitted and scaling can be easily corrected. It is characterized by having many advantages such as no need for management. However, the conventional visible light laser using visible light requires an operation in a dark room or under a red light for handling.

  With recent advances in laser technology, diversification of laser light sources has progressed, and UV (ultraviolet light) laser exposure apparatuses have been developed. In order to cope with UV (ultraviolet light) laser exposure, a photosensitive element with very high sensitivity and excellent resolution is required, and the current photosensitive element cannot cope with it, and UV (ultraviolet light) laser exposure. A special photosensitive element has been newly developed. However, since the throughput is still inadequate, the spread of UV (ultraviolet light) laser exposure apparatuses has been delayed compared to expectations. Although the throughput depends on the scanning speed of the laser, the current problem is that the scanning speed cannot be increased because the sensitivity of the photosensitive element is not mechanical and the sensitivity of the photosensitive element is insufficient. In addition, LDI is often used mainly in the tenting method, and high tenting properties are required.

  Although printed wiring board manufacturing using UV (ultraviolet light) laser exposure is very advantageous for manufacturing small quantities and other types, it has been slow to spread due to low throughput. In order to improve the throughput, a highly sensitive photosensitive element is required. A photoimage-forming composition using a hexaarylbisimidazole compound (hereinafter abbreviated as HABI) in a mixture of a leuco dye and other additives is known (for example, see Patent Document 1). Further, 2,2 ′, 5-tris- (o-chlorophenyl) -4- (3,4-dimethoxyphenyl) -4 ′, 5′-diphenylbiimidazole (hereinafter abbreviated as TCDM-HABI) and the like 2- A combination of a HABI derivative and a leuco dye that is more sensitive than (o-chlorophenyl) -4,5-diphenylimidazole dimer (hereinafter abbreviated as Cl-HABI) is also known (for example, see Patent Document 2). Furthermore, in order to achieve high sensitivity, a hydrogen donor is used together with HABI and a leuco dye (see, for example, Patent Document 3). As these hydrogen donors, organic thiols such as 2-mercaptobenzothiazole, tertiary amines, N-phenylglycine (hereinafter abbreviated as NPG) and the like are used, and N-phenylglycine is used from the viewpoint of increasing sensitivity. Particularly preferred. As a result of such efforts to increase sensitivity, sensitivity has improved and has reached a practical level in laser exposure. However, in actual use, the tenting property is not sufficient, so that a decrease in yield has been a problem.

  For improving tenting properties, for example, a photosensitive resin composition containing a high molecular weight binder polymer (see, for example, Patent Document 4) and a photosensitive resin composition containing a polyfunctional monomer (for example, Patent Document 5). See). However, in these methods, although the tenting property is improved in the batch exposure used for the normal mask exposure, the tenting property is low in the laser exposure even when compared with the same surface hardening condition by the step tablet. was there. Therefore, in the laser exposure, since the tenting is low at an exposure amount for obtaining a desired resolution, it is unavoidable to increase the exposure amount and improve the tenting property. As a result, throughput has been reduced with increasing exposure.

US Pat. No. 4,311,783

JP 62-66254 A U.S. Pat. No. 3,390,996 Japanese Patent No. 3252801 JP 2001-117225 A

  An object of the present invention is to provide a photosensitive resin composition useful for increasing the density and yield of a printed wiring board manufactured using laser exposure, a photosensitive element using the same, a method for manufacturing a photoresist pattern, and printing It is to provide a method for manufacturing a wiring board.

In order to solve the above problems, the present invention provides an ethylenically unsaturated group comprising (A) a binder polymer and (B) a photopolymerizable compound having 3 or more ethylenically unsaturated groups in one molecule as essential components. In the photosensitive resin composition containing (C1) a hexaarylbisimidazole compound and (C2) a hydrogen donor as a photopolymerization initiator (C) and (C) a photopolymerization initiator, The present invention relates to a photosensitive resin composition having the characteristics shown in a) to (c).
(A) The photosensitive resin composition layer coated using the photosensitive resin composition exhibits an absorbance of 0.2 to 0.8 with respect to monochromatic light used for exposure in the range of 340 to 410 nm.
(B) The photosensitive resin composition layer formed on the substrate is exposed to the monochromatic light and then developed with a developing solution, and the photoresist pattern has an aspect ratio of 0.7 or more.
(C) After forming the photosensitive resin composition layer on a substrate having 24 holes with a diameter of 6 mm and exposing with a light exposure amount of 20 steps after development of the 41-step tablet, exposure is performed. When the development process is performed three times, the hole breakage rate is 10% or less.

  Moreover, in the photosensitive resin composition layer coated using the photosensitive resin composition, it is preferable to exhibit an absorbance of 0.3 to 0.6 with respect to monochromatic light used for exposure in the range of 340 to 410 nm. .

  The component (C3) preferably contains a diaminobenzophenone compound represented by the general formula (1) or a coumarin compound represented by the general formula (2).

  Moreover, in this invention, the compounding quantity of (A) component and (B) component is 40-80 weight part of (A) component with respect to 100 weight part of total amounts of (A) component and (B) component, (B ) The component is preferably 20 to 60 parts by weight. Moreover, it is preferable that the compounding quantity of (C) component is 0.1-20 weight part with respect to 100 weight part of total amounts of (A) component and (B) component.

The present invention also includes (A) a binder polymer and (B) a photopolymerizable compound having 3 or more ethylenically unsaturated groups in one molecule as an essential component. A photosensitive resin composition containing at least one photopolymerizable compound and (C) a hexaarylbisimidazole compound and (C2) a hydrogen donor as a photopolymerization initiator is coated on a support and dried. The present invention relates to a photosensitive element having the following characteristics (a) to (c).
(A) The photosensitive resin composition layer of the photosensitive element exhibits an absorbance of 0.2 to 0.8 for monochromatic light used for exposure in the range of 340 to 410 nm.
(B) The photosensitive resin composition layer formed on the substrate using the photosensitive element is exposed to the monochromatic light, and then developed with a developer, and the photoresist pattern has an aspect ratio of 0. 7 or more.
(C) After forming the photosensitive resin composition layer on a substrate having 24 holes with a diameter of 6 mm and exposing with a light exposure amount of 20 steps after development of the 41-step tablet, exposure is performed. When the development process is performed three times, the hole breakage rate is 10% or less.
The photosensitive element of the present invention is preferably a photosensitive element formed by laminating a protective film so as to be in contact with the photosensitive resin composition layer.

The present invention also includes (A) a binder polymer and (B) a photopolymerizable compound having 3 or more ethylenically unsaturated groups in one molecule as an essential component. A photopolymerizable compound having at least one, and (C) a photopolymerization initiator comprising (C1) a hexaarylbisimidazole compound and (C2) a hydrogen donor, and having the characteristics shown in the following (a) to (c) The present invention relates to a method for producing a photoresist pattern, wherein a photosensitive resin composition layer is formed on a substrate using a photosensitive resin composition, followed by scanning exposure with an ultraviolet laser and a development process.
(A) The photosensitive resin composition layer coated using the photosensitive resin composition exhibits an absorbance of 0.2 to 0.8 with respect to monochromatic light used for exposure in the range of 340 to 410 nm.
(B) The photosensitive resin composition layer formed on the substrate is exposed to the monochromatic light and then developed with a developing solution, and the photoresist pattern has an aspect ratio of 0.7 or more.
(C) After forming the photosensitive resin composition layer on a substrate having 24 holes with a diameter of 6 mm and exposing with a light exposure amount of 20 steps after development of the 41-step tablet, exposure is performed. When the development process is performed three times, the hole breakage rate is 10% or less.

The present invention also includes (A) a binder polymer and (B) a photopolymerizable compound having 3 or more ethylenically unsaturated groups in one molecule as an essential component. A photopolymerizable compound having at least one, and (C) a photopolymerization initiator comprising (C1) a hexaarylbisimidazole compound and (C2) a hydrogen donor, and having the characteristics shown in the following (a) to (c) The photosensitive resin composition is used to form a photosensitive resin composition layer on the substrate, scan exposure with an ultraviolet laser, and a photoresist pattern through a development process, and then etch the layer to be processed of the substrate or the substrate The present invention relates to a method for manufacturing a printed wiring board, wherein a layer to be processed is selectively plated.
(A) The photosensitive resin composition layer coated using the photosensitive resin composition exhibits an absorbance of 0.2 to 0.8 with respect to monochromatic light used for exposure in the range of 340 to 410 nm.
(B) The photosensitive resin composition layer formed on the substrate is exposed to the monochromatic light and then developed with a developing solution, and the photoresist pattern has an aspect ratio of 0.7 or more.
(C) After forming the photosensitive resin composition layer on a substrate having 24 holes with a diameter of 6 mm and exposing with a light exposure amount of 20 steps after development of the 41-step tablet, exposure is performed. When the development process is performed three times, the hole breakage rate is 10% or less.

  As described above, the photosensitive resin composition of the present invention, the photosensitive element using the same, the method for producing a photoresist pattern, and the method for producing a printed wiring board have improved photosensitivity, resolution, and tenting in laser exposure. It has an excellent effect of increasing the density of printed wiring boards and improving the yield.

  Hereinafter, the present invention will be described in detail.

  The photosensitive resin composition of the present invention comprises at least (A) a binder polymer and (B) an ethylenically unsaturated group having an essential component a photopolymerizable compound having three or more ethylenically unsaturated groups in one molecule. A photopolymerizable compound having one or more in one molecule and (C) a photopolymerization initiator are contained.

  As the binder polymer of component (A), for example, one or more of acrylic resins, styrene resins, epoxy resins, amide resins, amide epoxy resins, alkyd resins, phenol resins, and the like can be used. . From the standpoint of alkali developability, it is preferable to use an acrylic resin. If necessary, the binder polymer may have a photosensitive group. These are used alone or in combination of two or more.

  This component (A) can be produced, for example, by radical polymerization of a polymerizable monomer. Examples of the polymerizable monomer include styrene, polymerizable styrene derivatives, acrylamide, acrylonitrile, esters of vinyl alcohol, (meth) acrylic acid alkyl ester, (meth) acrylic acid tetrahydrofurfuryl ester, (meth) acrylic. Acid dimethylaminoethyl ester, (meth) acrylic acid diethylaminoethyl ester, (meth) acrylic acid glycidyl ester, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meta) ) Acrylate, (meth) acrylic acid, α-bromo (meth) acrylic acid, α-chloro (meth) acrylic acid, β-furyl (meth) acrylic acid, β-styryl (meth) acrylic acid, maleic acid, maleic acid Anhydride, maleic acid monoester, fumaric acid, Lee cinnamic acid, alpha-cyanocinnamic acid, itaconic acid, crotonic acid, propiolic acid. These are used alone or in combination of two or more.

  As the polymerizable styrene derivative, vinyl toluene, α-methyl styrene, p-methyl styrene, p-ethyl styrene, or the like can be used. As the esters of vinyl alcohol, vinyl-n-butyl ether or the like can be used. Examples of the (meth) acrylic acid alkyl ester include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, (meth ) Hexyl acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and structural isomers thereof. Examples of the maleic acid monoester include monomethyl maleate, monoethyl maleate, monoisopropyl maleate and the like. Any of these may be used alone or in combinations of two or more.

  The component (A) preferably contains a carboxyl group because it is desirable that the component (A) is soluble or swellable in an alkaline aqueous solution from the viewpoints of peeling properties and environmental conservation. Such a binder polymer can be produced, for example, by radical polymerization of a polymerizable monomer having a carboxyl group and another polymerizable monomer. As the polymerizable monomer having a carboxyl group, methacrylic acid is preferable. The acid value of the binder polymer is preferably 100 mgKOH / g or more so that the development time does not become too long, and from the viewpoint of developer resistance of the photocured photosensitive resin composition, it should be 500 mgKOH / g or less. Preferably, it is 100-300 mgKOH / g.

  The component (A) preferably contains styrene and / or a styrene derivative as a polymerizable monomer from the viewpoint of adhesion and release characteristics. In order to contain styrene and / or a styrene derivative as a copolymerization component and to improve both the adhesion and the release characteristics, the proportion of styrene and / or styrene derivative in the copolymer is 3% by weight from the viewpoint of adhesion. From the viewpoint of the size of the peeled piece and the peel time, it is preferably 30% by weight or less, more preferably 4 to 28% by weight, and particularly preferably 5 to 27% by weight.

  The weight average molecular weight of the component (A) (measured by gel permeation chromatography (GPC) and converted by a calibration curve using standard polystyrene) is preferably 20,000 or more from the viewpoint of developer resistance. The development time is preferably 300,000 or less, more preferably 25,000 to 150,000 so that the development time does not become too long.

  These binder polymers are all 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 comprising different copolymerization components, two or more types of binder polymers having different weight average molecular weights, and two or more types of binder polymers having different degrees of dispersion are used. Examples thereof include a binder polymer. A polymer having a multimode molecular weight distribution described in JP-A No. 11-327137 can also be used.

  Although there is no restriction | limiting in particular as a photopolymerizable compound which has 3 or more of ethylenically unsaturated groups in 1 molecule which is an essential component of (B) component in this invention, The photopolymerizable compound which has a structure of (3) Is preferred. In the general formula (3), Z is not particularly limited as long as it is a trivalent or higher valent organic group, but for example, a group containing an aliphatic hydrocarbon having 3 to 10 carbon atoms, or a group having 3 to 10 carbon atoms having a hetero atom. Examples include a group containing an aliphatic hydrocarbon, a group containing a melamine skeleton, and a group containing an isocyanuric acid skeleton.

Among these, a group containing an isocyanuric acid skeleton is preferable from the viewpoint of high resolution. R ¹ represents a hydrogen atom or a methyl group, R ² represents an ethylene group or a propylene group, R ³ represents an ethylene group or a propylene group, and R ² and R ³ on the same chain are necessarily different groups. . In the general formula (3), l is an integer of 3 or more, preferably 3 to 10, more preferably 3 to 6, and particularly preferably 3. M and n represent the number of repeating units, and are an integer of 0 or more that satisfies m + n ≧ 1, m + n is preferably 1 to 20, more preferably 1 to 10, and 1 to 5 It is particularly preferred that

In addition, when the number of repeating units of — (R ² —O) — and — (R ³ —O) — is 2 or more, two or more R ² and two or more R ³ are the same or different. In the case where R ² and R ³ are composed of two or more alkylene groups, two or more of — (R ² —O) — and — (R ³ —O) — are present at random. Or may exist in blocks.

  Examples of the photopolymerizable compound having the structure of the general formula (3) include trimethylolpropane polyethoxytri (meth) acrylate, trimethylolpropane polypropoxytri (meth) acrylate, and glyceryl polyethoxypolypropoxytri (meth) acrylate. , Trimethylolpropane polyethoxypolypropoxytri (meth) acrylate, pentaerythritol polyethoxypolypropoxytri (meth) acrylate, pentaerythritol polyethoxypolypropoxytetra (meth) acrylate, trimethylolethane polyethoxypolypropoxytri (meth) acrylate , Dipentaerythritol polyethoxypolypropoxytri (meth) acrylate, dipentaerythritol polyethoxypolypropoxytetra (meth) Acrylate, dipentaerythritol polyethoxy propoxy penta (meth) acrylate, dipentaerythritol polyethoxy propoxy hexa (meth) acrylate, tris ((meth) acryloxy tetraethylene glycol isocyanate) hexamethylene isocyanurate. Of these, tris (methacryloyloxytetraethylene glycol isocyanate hexamethylene) isocyanurate (UA-21: manufactured by Shin-Nakamura Chemical Co., Ltd., product name) is preferable from the viewpoint of high resolution.

  Examples of the photopolymerizable compound having three or more ethylenically unsaturated groups in one molecule other than the photopolymerizable compound having the structure of the general formula (3) include trimethylolpropane tri (meth) acrylate and tetramethylol. Examples include methanetri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, and dipentaerythritol hexa (meth) acrylate. These photopolymerizable compounds having three or more ethylenically unsaturated groups in one molecule are used alone or in combination of two or more.

  The photosensitive resin composition of the present invention has a photopolymerizable compound having three or more ethylenically unsaturated groups in one molecule and at least one polymerizable ethylenically unsaturated group in the other molecule. A photopolymerizable compound can be used in combination. The photopolymerizable compound having at least one polymerizable ethylenically unsaturated group in the molecule other than the photopolymerizable compound having three or more ethylenically unsaturated groups in one molecule is not particularly limited, For example, it is obtained by reacting α, β-unsaturated carboxylic acid with a compound obtained by reacting α, β-unsaturated carboxylic acid with polyhydric alcohol, bisphenol A (meth) acrylate compound, or glycidyl group-containing compound. Compounds, urethane monomers such as (meth) acrylate compounds having a urethane bond in the molecule, nonylphenoxypolyethyleneoxyacrylate, phthalic acid compounds, (meth) acrylic acid alkyl esters, and the like. These are used alone or in combination of two or more.

  From the viewpoint of plating resistance and adhesion, it is preferable that the component (B) contains a bisphenol A (meth) acrylate compound or a (meth) acrylate compound having a urethane bond in the molecule. In addition, a photopolymerizable compound having three or more ethylenically unsaturated groups in one molecule, a photopolymerizable compound having one polymerizable ethylenically unsaturated bond in the molecule, and two or more polymerizations in the molecule. It can be used in combination with a photopolymerizable compound having a possible ethylenically unsaturated bond.

  Examples of the compound obtained by reacting the 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 2 propylene groups. 14 polypropylene glycol di (meth) acrylate, polyethylene / polypropylene glycol di (meth) acrylate having 2 to 14 ethylene groups and 2 to 14 propylene groups, trimethylolpropane di (meth) acrylate, etc. Is mentioned. These are used alone or in combination of two or more.

  Examples of the bisphenol A-based (meth) acrylate compound include 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane and 2,2-bis (4-((meth) acryloxypolypropoxy). Phenyl) propane, 2,2-bis (4-((meth) acryloxypolybutoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxypolyethoxypolypropoxy) phenyl) propane and the like It is done. Examples of the 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-((meta ) 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) acryloxynonane) Xyl) 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) acryloxy) Hexadecaethoxy) phenyl) propane and the like, and 2,2-bis (4- (methacryloxypentaethoxy) phenyl) propane is BPE- 00 (made by Shin-Nakamura Chemical Co., Ltd., product name) and 2,2-bis (4- (methacryloxypentadecaethoxy) phenyl) propane is BPE-1300 (Shin-Nakamura Chemical) It is commercially available as a product name manufactured by Kogyo Co., Ltd. The number of ethylene oxide groups in one molecule of the 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane is preferably 4-20, and more preferably 8-15. These are used alone or in combination of two or more.

  Examples of the (meth) acrylate compound having a urethane bond in the molecule include a (meth) acryl monomer having an OH group at the β-position and a diisocyanate compound (isophorone diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate). , 1,6-hexamethylene diisocyanate, etc.), tris ((meth) acryloxytetraethylene glycol isocyanate) hexamethylene isocyanurate, EO-modified urethane di (meth) acrylate, EO, PO-modified urethane di (meth) acrylate Etc. Examples of the EO-modified urethane di (meth) acrylate include UA-11 (manufactured by Shin-Nakamura Chemical Co., Ltd., product name). Examples of EO, PO-modified urethane di (meth) acrylate include UA-13 (manufactured by Shin-Nakamura Chemical Co., Ltd., product name). These are used alone or in combination of two or more. In the above, EO represents ethylene oxide, and the EO-modified compound has an ethylene oxide group block structure. PO represents propylene oxide, and the PO-modified compound has a block structure of propylene oxide groups.

  Examples of the nonylphenoxypolyethyleneoxyacrylate include nonylphenoxytetraethyleneoxyacrylate, nonylphenoxypentaethyleneoxyacrylate, nonylphenoxyhexaethyleneoxyacrylate, nonylphenoxyheptaethyleneoxyacrylate, nonylphenoxyoctaethyleneoxyacrylate, nonylphenoxynonaethylene Examples include oxyacrylate, nonylphenoxydecaethyleneoxyacrylate, and nonylphenoxyundecaethyleneoxyacrylate. These are used alone or in combination of two or more.

  Examples of the phthalic acid compounds include γ-chloro-β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate, β-hydroxyalkyl-β ′-(meth) acryloloxyalkyl-o. -A phthalate etc. are mentioned. These are used alone or in combination of two or more.

In the present invention, (meth) acrylic acid means acrylic acid and methacrylic acid corresponding thereto, (meth) acrylate means acrylate and methacrylate corresponding thereto, and (meth) acryloyl group means acryloyl. Means a group and the corresponding methacryloyl group.
(C) As a photoinitiator of a component, it is normally used in multiple combinations. Examples of the (C1) hexaarylbisimidazole compound include 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (2,6-difluorophenyl) -4,5-di (m- Methoxyphenyl) imidazole dimer, 2- (o-chlorophenyl) -4,5-di (methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2 2,4,5-triarylimidazole dimers such as-(o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer 2,2 ′, 5-tris- (o-chlorophenyl) -4- (3,4-dimethoxyphenyl) -4 ′, 5′-diphenylbiimidazole, 2,2 ′ 4,4′-tetra- (o-chlorophenyl) -5,5′-bis- (3,4-dimethoxyphenyl) -biimidazole and the like. These are used alone or in combination of two or more. In particular, 2,2 ′, 5-tris- (o-chlorophenyl) -4- (3,4-dimethoxyphenyl) -4 ′, 5′-diphenylbiimidazole is preferable from the viewpoint of plating resistance and high sensitivity. .

  Examples of the (C2) hydrogen donor include organic thiols such as 2-mercaptobenzothiazole, tertiary amines, and N-phenylglycine derivatives. From the viewpoint of increasing sensitivity, N-phenylglycine is preferable. preferable.

Moreover, the photopolymerization initiator of (C3) component other than the said (C1) component and (C2) component can be contained in the photosensitive resin composition of this invention. Examples thereof include, for example, benzophenone, N, N′-tetramethyl-4,4′-diaminobenzophenone (Michler ketone), N, N′-tetraethyl-4,4′-diaminobenzophenone (hereinafter abbreviated as EAB). N, N′-tetraalkyl-4,4′-ginzoin compounds, benzyl derivatives such as benzyldimethyl ketal, iodonium salt compounds, diphenyliodonium salts such as 4,4′-bis (tert-butyl) phenyliodonium triflate, Acridine derivatives such as 9-phenylacridine, 1,7-bis (9,9′-acridinyl) heptane, 7-aminobenzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 2-methyl-1- [4- (methylthio) phenyl] -2-morpholine -Coumarins such as aromatic ketones such as propanone-1, quinones such as alkyl anthraquinones, benzoin ether compounds such as benzoin alkyl ether, bediethylamino-4-methylcoumarin (hereinafter abbreviated as DAMC) such as benzoin and alkylbenzoin Compound etc. are mentioned. Among these, from the viewpoint of increasing sensitivity, the compound represented by (1) or the general formula (2) is preferable, and EAB or DAMC is particularly preferable. These may be used alone or in combination of two or more. In (1), R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. In general formula (2), R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. Examples of the alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and an isobutyl group.

  Next, the preferable compounding quantity of each component is demonstrated. The blending amount of the component (A) is based on the hardness (brittleness) of the photocured product and the coating property when used as a photosensitive element with respect to 100 parts by weight of the total amount of the components (A) and (B). To 40 parts by weight or more, preferably 80 parts by weight or less, more preferably 40 to 60 parts by weight from the viewpoint of increasing sensitivity.

  The blending amount of the component (B) is preferably 20 parts by weight or more from the viewpoint of high sensitivity with respect to 100 parts by weight of the total amount of the component (A) and the component (B), and the hardness (brittleness of the photocured product) From the viewpoint of (a), it is preferably 60 parts by weight or less, and more preferably 40 to 60 parts by weight.

  The blending ratio of the photopolymerizable compound having 3 or more ethylenically unsaturated groups in the component (B) per molecule is 5% by weight or more from the viewpoint of tenting properties with respect to the total amount of the component (B). It is preferable that it is 70% by weight or less from the viewpoint of peelability, and it is particularly preferably 10 to 50% by weight.

  The content of the component (C) is preferably 0.1 parts by weight or more from the viewpoint of increasing sensitivity with respect to 100 parts by weight of the total amount of the components (A) and (B), and from the viewpoint of the photocuring degree It is preferably 20 parts by weight or less, particularly preferably 0.2 to 10 parts by weight. If this amount exceeds 20 parts by weight, absorption on the surface of the photosensitive composition layer increases during exposure, and the internal photocured product tends to be insufficient.

  The content of the component (C1) is preferably 0.1 parts by weight or more from the viewpoint of high sensitivity, and is preferably 4 parts by weight or less in order to obtain a favorable photoresist shape in monochromatic light exposure. 1 to 3 parts by weight is particularly preferable. The content of the component (C2) is preferably 0.05 parts by weight or more from the viewpoint of increasing sensitivity, and is preferably 1 part by weight or less from the viewpoint of obtaining good storage stability. -0.5 parts by weight are particularly preferred.

  Moreover, it is preferable to contain EAB or DAMC as described above for further enhancement of sensitivity. The content of EAB or DAMC is preferably 0.005 parts by weight or more from the viewpoint of increasing sensitivity, and preferably 0.3 parts by weight or less from the viewpoint of obtaining a good photoresist shape. It is particularly preferable that the amount be 01 to 0.12 parts by weight.

  In addition to the above components, the photosensitive resin composition of the present invention includes, as necessary, thermal coloring inhibitors such as dyes, color formers and glycidyl ether compounds, plasticizers, pigments, fillers, antifoaming agents, Imaging agents such as flame retardants, stabilizers, adhesion-imparting agents, leveling agents, peeling accelerators, antioxidants, fragrances, leuco dyes, etc. are each 0 for 100 parts by weight of the total amount of component (A) and component (B). About 0.01 to 20 parts by weight can be contained.

  The photosensitive resin composition of the present invention is, for example, a solvent such as methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N-dimethylformamide, propylene glycol monomethyl ether, or the like as necessary. It can melt | dissolve in a mixed solvent and can apply | coat as a solution of solid content about 30 to 60 weight%. This photosensitive resin composition is applied on a metal surface such as copper, copper-based alloy, iron, iron-based alloy and dried, and then used with a protective film as required, or in the form of a photosensitive element. It is preferable to be used.

  The photosensitive resin composition layer in the present invention is formed, for example, by applying a solution of the photosensitive resin composition containing the above components on a support and drying it. The formed photosensitive resin composition layer has an absorbance at an exposure wavelength of 0.2 to 0.8, preferably 0.3 to 0.6. The tenting property is good when the absorbance is 0.8 or less, but when it exceeds 0.8, the photocuring degree at the bottom of the photosensitive resin composition layer is lowered and the tenting property is lowered. If it is less than 0.2, the light irradiated at the time of exposure is excessively transmitted, whereby the cross-sectional shape of the line after development becomes trapezoidal. The absorbance can be measured by, for example, a UV spectrometer. The photopolymerization rate at the surface and bottom of the photoresist can be measured by the FT-IR ATR method or the like.

  In addition, the formed photosensitive resin composition layer has an aspect ratio of 0.7 or more of a photoresist pattern generated by developing with a developer after being exposed to the monochromatic light. When the aspect ratio is 0.7 or more, the resolution is excellent, and thus it is useful for increasing the density of the printed wiring board. If the aspect ratio is less than 0.7, the resolution is inferior, and it is difficult to increase the density of the printed wiring board.

  Further, the photosensitive resin composition layer is formed on a substrate having 24 holes with a diameter of 6 mm, and after exposure with an exposure amount of 20 steps after development of the 41-step tablet, the development is performed. When the process is performed three times, the hole breakage rate is 10% or less. When the hole breakage rate is 10% or less, the adhesive property between the photoresist and the substrate is excellent, which is useful for improving the yield of the printed wiring board. If the hole tear rate exceeds 10%, the adhesion between the photoresist and the substrate is inferior. Therefore, there is a possibility that the entire or partial photoresist pattern may be peeled off during development. It causes the yield to decrease.

  Next, the photosensitive element according to the present invention, that is, the photosensitive element in which the above-described photosensitive resin composition layer according to the present invention is formed on a support will be described with reference to the drawings.

  FIG. 1 schematically shows an embodiment of a photosensitive element. The photosensitive element 1 includes a support 11 and a photosensitive resin composition layer 12 formed thereon. .

  As the support 11, for example, a polymer film having heat resistance and solvent resistance such as polyethylene terephthalate, polypropylene, polyethylene, and polyester can be preferably used. The thickness of the polymer film serving as a support is preferably 1 to 100 μm.

  Although the formation method of the photosensitive resin composition layer 12 on the support body 11 is not specifically limited, For example, it can obtain preferably by apply | coating and drying the solution of the photosensitive resin composition. The thickness of the photosensitive resin composition layer to be applied is adjusted so that the absorbance is 0.2 to 0.8, and the thickness after drying is preferably about 1 to 100 μm. Therefore, it is preferably 20 μm or more, and preferably 50 μm or less from the viewpoint of increasing sensitivity. From the viewpoint of a balance between the two, 25 μm to 40 μm is particularly preferable. The coating can be performed by a known method such as a roll coater, a comma coater, a gravure coater, an air knife coater, a die coater, or a bar coater. Drying can be performed at 70 to 150 ° C. for about 5 to 30 minutes. In addition, the amount of the remaining organic solvent in the photosensitive resin composition layer 12 is preferably 2% by weight or less from the viewpoint of preventing diffusion of the organic solvent in the subsequent step.

  The surface of the photosensitive resin composition layer of the photosensitive element 1 is preferably covered with a protective film (not shown) made of a polymer film such as polyethylene or polypropylene. The thickness of the protective film is preferably 5 μm or more from the viewpoint of strength, and preferably 30 μm or less from the viewpoint of inexpensiveness. As the protective film, it is preferable to select one having a smaller adhesive force between the photosensitive resin composition layer and the protective film than the adhesive force between the photosensitive resin composition layer and the support, but the same polymer film One of the above may be used as a support and the other as a protective film may be laminated on both sides of the photosensitive resin composition layer. Moreover, it is preferable to use a protective film having a low fish eye.

  Since these support and protective film must be removable later from the photosensitive resin composition layer, they should not be subjected to surface treatment that makes removal impossible, but if necessary And surface treatment may be performed. For example, these supports and protective films may be subjected to antistatic treatment as necessary.

  The photosensitive element having a two-layer or three-layer structure composed of a support, a photosensitive resin composition layer, and, if necessary, a protective film is not shown in the drawing, but is not shown in the figure. You may have intermediate | middle layers, such as an absorption layer and a gas barrier layer, and protective layers.

  The photosensitive element thus obtained is stored, for example, as it is or by laminating a protective film on the surface of the photosensitive resin composition layer and winding it around a cylindrical core in a roll shape. In that case, it is preferable to wind up so that a support body may become the 1st outer side. An end face separator is preferably installed on the end face of the wound photosensitive element roll from the viewpoint of end face protection, and a moisture-proof end face separator is preferably installed from the viewpoint of edge fusion resistance. Further, as a packing method, it is preferable to wrap and package in a moisture-permeable black sheet. Examples of the core include plastics such as polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, ABS resin (acrylonitrile-butadiene-styrene copolymer).

  Next, a method for producing a photoresist pattern according to the present invention will be described with reference to FIG. 2 schematically showing an example of the process.

First, as the step (i), the above-described photosensitive resin composition layer of the present invention is laminated on a substrate (circuit forming substrate) 2. Although the lamination method is arbitrary, for example, as shown in FIG. 2A, the photosensitive element 1 is placed on the substrate 2 so that the photosensitive resin composition layer 12 is in close contact with the surface of the substrate 2. And stack. Prior to lamination, when a protective film (not shown) is present on the photosensitive resin composition layer 12 of the photosensitive element 1, the protective film is removed. As this lamination method, for example, the photosensitive resin composition layer 12 is pressure-bonded to the substrate 2 at a pressure of about 0.1 to 1 MPa (about 1 to 10 kgf / cm ² ) while being heated to about 70 to 130 ° C. The method of laminating is mentioned. It is also possible to laminate under reduced pressure. In addition, although the surface of the board | substrate 2 laminated | stacked is a metal surface normally, there is no restriction | limiting in particular. In addition, if the photosensitive resin composition layer is heated to 70 to 130 ° C. as described above, it is not necessary to pre-heat the substrate in advance, but the substrate is pre-heated in order to further improve the stackability. You can also

  After the lamination of the photosensitive resin composition layer is completed, as the step (ii), the photosensitive resin composition layer in the exposed portion is photocured by irradiating an actinic ray in an image form. As a method of irradiating actinic rays in an image form, for example, as shown in FIG. 2 (b), actinic rays are imaged on the photosensitive resin composition layer 12 through a negative or positive mask pattern 3 called an artwork. The photosensitive resin composition layer 12 in the exposed area can be photocured. As the active light source, a known light source, for example, a carbon arc lamp, a mercury vapor arc lamp, an ultra-high pressure mercury lamp, a high-pressure mercury lamp, a xenon lamp, or the like that effectively emits ultraviolet rays, visible rays, or the like is used.

  Further, laser direct drawing or DLP (Digital Light Processing) exposure can be performed without using a mask pattern. The present invention is particularly effective in an exposure method using actinic rays using monochromatic light as a light source. Here, the monochromatic light means that only light having a specific wavelength is extracted from a light source having a full wavelength or a plurality of oscillation wavelengths such as an Ar ion laser, a solid state laser, a semiconductor laser, or a lamp of a mercury lamp by an interference filter. Means something. The wavelength region of monochromatic light is generally 340 nm to 410 nm. In addition, the exposure of process (ii) can be performed in the state in which the support body 11 existed, unless the light irradiation to the photosensitive resin composition layer 12 was prevented (when the support body is transparent etc.).

  After exposure, when a support is present on the photosensitive resin composition layer, after removing the support, as a step (iii), the photosensitive resin composition layer in the unexposed area is selectively developed by development. As a result, the photoresist pattern 121 is formed as shown in FIG. Development is performed by, for example, wet development, dry development, or the like. In the case of wet development, for example, using a developer corresponding to the composition of the photosensitive resin composition layer such as an alkaline aqueous solution, aqueous developer, organic solvent, etc., for example, dip method, spray method, brushing, slapping, etc. This is performed by a known method. If necessary, two or more developing methods may be used in combination.

  Examples of the alkaline aqueous solution include a dilute solution of 0.1 to 5 wt% sodium carbonate, a dilute solution of 0.1 to 5 wt% potassium carbonate, a dilute solution of 0.1 to 5 wt% sodium hydroxide, and the like. It is done. The pH of the alkaline aqueous solution is preferably in the range of 9 to 11, and the temperature is adjusted according to the developability of the photosensitive resin composition layer. Further, a surfactant, an antifoaming agent, an organic solvent, or the like may be mixed in the alkaline aqueous solution.

The development time is a state in which the photosensitive resin composition layer is laminated on the substrate and is not exposed, and when the support is present on the photosensitive resin composition layer, after removing the support, When developing by the above method, the minimum development time is the minimum time for removing the photosensitive resin composition layer, and the normal development time is twice the minimum development time. However, it does not necessarily have to be doubled, and development can be performed in a range of 1 to 6 times depending on differences in materials and processes. As a treatment after development, the formed photoresist pattern may be further cured by performing heating at 60 to 250 ° C. or exposure at about 0.2 to 10 J / cm ² as necessary.

  Next, a method for manufacturing a printed wiring board according to the present invention will be described with reference to FIGS. 3 and 4 schematically showing an example of the process.

  The steps until the photoresist pattern is formed are the same as those described in the above-described photoresist pattern manufacturing method including the (i) stacking step, (ii) exposure step, and (iii) development step. Regarding the subsequent circuit formation step (iv), FIG. 3 shows a subtractive method using etching, and FIG. 4 shows a semi-additive method using plating.

  After the photoresist pattern 121 is formed, as a step (iv), as shown in FIG. 3B, a substrate (for circuit formation) having the layer 21 to be processed on the surface using the formed photoresist pattern 121 as a mask. Substrate) 2 to be processed 21 or, as shown in FIG. 4 (b), selective plating is performed on processed layer 21 to form, for example, a plating layer 22 made of copper or the like. To do. For example, a cupric chloride solution, a ferric chloride solution, an alkali etching solution, or the like can be used for etching the processing layer 21 formed of a metal surface in FIG. Moreover, as a plating method in FIG.4 (b), copper plating, solder plating, nickel plating, gold plating etc. are mentioned, for example.

  Finally, as shown in FIGS. 3 (c) and 4 (c), the photoresist pattern 121 remaining on the substrate 2 is peeled off with, for example, a stronger alkaline aqueous solution than the alkaline aqueous solution used for development. The printed wiring board 4 on which the circuit 211 is formed can be obtained. In the case of the semi-additive method, as shown in FIG. 4D, after the photoresist pattern 121 is peeled off, the layer 21 to be processed is also removed by, for example, a quick etching method. As said strong alkaline aqueous solution, 1-10 weight% sodium hydroxide aqueous solution, 1-10 weight% potassium hydroxide aqueous solution, etc. are used, for example. Examples of the peeling method include an immersion method and a spray method. The printed wiring board on which the photoresist 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 in more detail with reference to examples. However, the present invention is not limited to these examples without departing from the technical idea of the present invention.
(Examples 1-3 and Comparative Examples 1-3)
Each component shown in Table 1 was mixed and dissolved at a weight ratio shown in the same table to obtain a solution of a photosensitive resin composition.

  Next, each obtained photosensitive resin composition solution was uniformly applied onto a 16 μm-thick polyethylene terephthalate film (trade name GS type, manufactured by Teijin Limited), and dried for 10 minutes with a 100 ° C. hot air convection dryer. Thus, a photosensitive element was obtained. The film thickness after drying of the photosensitive resin composition layer was 40 μm.

  On the other hand, the copper surface of a copper-clad laminate (trade name MCL-E-67 manufactured by Hitachi Chemical Co., Ltd.), which is a glass epoxy material in which copper foil (thickness 35 μm) is laminated on both sides, has a brush equivalent to # 600. Polishing was performed using a polishing machine (manufactured by Sankei Co., Ltd.), washed with water, and then dried with an air stream. Next, after heating the copper clad laminate to 80 ° C., the photosensitive element obtained above was 0.4 MPa at 120 ° C. so that the photosensitive resin composition layer was in close contact with the copper surface. Laminate under pressure.

  When the copper-clad laminate with the photosensitive elements laminated is cooled to 23 ° C., the polyethylene terephthalate surface has a concentration region of 0.00 to 2.00, a concentration step of 0.05, and a tablet size of 20 mm × 187 mm. Using a direct measure DI-2050 manufactured by Pentax Co., Ltd., which is a laser exposure machine using a UV solid-state laser with a wavelength of 355 nm as a light source, which is in close contact with a photo tool having a 41-step tablet with a size of 3 mm × 12 mm for each step. And exposed. Next, the polyethylene terephthalate film was removed, and an unexposed portion was removed by spraying a 1.0 wt% sodium carbonate aqueous solution at 30 ° C. for 60 seconds (twice the minimum development time of 30 seconds). The exposure amount at which the number of remaining step steps after development of the 41-step tablet was 20 was defined as sensitivity.

  The absorbance of the photosensitive resin composition layer with respect to the exposure wavelength was determined by using a UV spectrometer (U-3310 spectrophotometer manufactured by Hitachi, Ltd.), a photosensitive resin first prepared to have a support film and a thickness of 40 μm on the measurement side. The photosensitive element which consists of a composition layer was set | placed, the support film was set | placed on the reference side, 550-300 nm was continuously measured by the absorbance mode, and it measured by reading the value of the light absorbency in exposure wavelength = 355nm.

  The resolution is a test pattern of direct measure DI-2050, the line width / space width is 30/30 to 100/100 (unit: μm), and the exposure is performed with the above-mentioned sensitivity exposure amount. The evaluation was based on the smallest value of the space width between the line widths where the unexposed part could be removed cleanly.

The aspect ratio is a pattern having the same line width / space width, and is exposed at the exposure amount having the sensitivity described above, and the smallest value of the space width between the line widths in which the unexposed portion can be removed cleanly by the development process ( a) and the film thickness of the photoresist (b) (ie, b / a). The larger this value, the higher the resolution of the thick photoresist. Is shown.
Moreover, the cross-sectional shape of the obtained photoresist pattern line was evaluated by confirming with a scanning electron microscope (S-2100A manufactured by Hitachi, Ltd.). The sensitivity and resolution are both evaluated better as the numerical value is smaller, and as the cross-sectional shape of the photoresist pattern line is rectangular, the shape is better.

For the tenting property, a 1.6 mm thick copper clad laminate having 24 holes with a diameter of 6 mm was used. The copper-clad laminate has a diameter of a copper-clad laminate (trade name MCL-E-67, manufactured by Hitachi Chemical Co., Ltd.), which is a glass epoxy material in which copper foil (thickness 35 μm) is laminated on both sides with a die cutter. Twenty-four 6 mm holes were made, and burrs generated when the holes were made were removed using a polishing machine having a brush equivalent to # 600 (manufactured by Sankei Co., Ltd.), which was used as a tenting evaluation substrate. . The photosensitive elements of Examples 1 to 3 and Comparative Examples 1 to 3 were laminated on both surfaces of the tenting evaluation substrate, and the entire surface was exposed with an exposure amount of 12 mJ / cm ² using the laser exposure machine. After removing the polyethylene terephthalate film, development for 60 seconds (twice the minimum development time of 30 seconds) was performed three times. At this time, a spray nozzle having an inner diameter of 1.2 mm (manufactured by Spraying System Japan Co., Ltd., square full cone type spray nozzle) is located at the point closest to the photoresist of the spray nozzle (tip of the spray nozzle) and the photoresist. Was used by spraying a 1.0 wt% sodium carbonate aqueous solution at a spray pressure of 0.18 MPa so as to sufficiently hit the entire surface of the photoresist. In addition, six spray nozzles were arranged side by side at intervals of 30 mm so that the 1.0 wt% sodium carbonate aqueous solution was sufficiently applied to the 24 holes. After development, the number of hole breaks was visually measured and evaluated as a tent tear rate, which was defined as tenting property. The lower the tent tear rate, the higher the tenting property, and it is desirable that the tent tear rate is zero.

  Tables 2 and 3 show the absorbance of each film, the sensitivity in laser exposure, the number of remaining ST steps, and the tent tear rate.

From Table 2 and Table 3, it can be seen that the films of Examples 1 to 3 have an aspect ratio of 0.7 or more and good tenting properties. It can also be seen that the resolution is good and the photoresist shape also shows an ideal rectangle. In addition, the absorbance is in the range of 0.2 to 0.8. On the other hand, when the absorbance is too low as in the film of Comparative Example 1, the tenting property is excellent, but the aspect ratio is less than 0.7, and the sensitivity is lowered and the photoresist shape is trapezoidal, which is practical. I understand that it is not. When the absorbance is too high as in the film of Comparative Example 2, the number of remaining ST steps is large and surface hardening is good, but the tenting property is poor and the aspect ratio is less than 0.7. Furthermore, it turns out that a photoresist shape becomes an inverted trapezoid and is not practical. In addition, even if the absorbance is in the range of 0.2 to 0.8 as compared with Comparative Example 3, the tenting property is poor when an ethylenically unsaturated compound having 3 or more unsaturated groups in one molecule is not included. I understand.
(Measurement of polymerization rate)
In order to examine in detail the influence of the absorbance of the film on the tenting properties, the sample of Comparative Example 2 was exposed with the exposure amount equivalent to 20 steps of the step tablet with the laser exposure machine with the polyethylene terephthalate film attached without laminating. Next, the polyethylene terephthalate film is removed, only the photosensitive resin composition layer of the film is taken out, and the FT-IR (infrared microscope AIM8000R manufactured by Shimadzu Corporation) is measured by the ATR method on the front and back surfaces of the exposed surface. did. The peak intensity in the vicinity of 1650 cm ⁻¹ derived from the unsaturated group of methacrylate was compared with the exposed and exposed surfaces of the photosensitive resin composition layer and the unexposed film photosensitive resin composition layer. The results are shown in FIG.

From FIG. 5, on the surface of the exposed surface, the peak intensity near 1650 cm ⁻¹ is greatly reduced compared to the unexposed peak intensity. This is presumably because the photopolymerizable compound is sufficiently cured. However, on the back surface of the exposed surface, the decrease rate with respect to the unexposed peak intensity was smaller than the peak intensity of the exposed surface. This result is considered to be because in photoexposure using monochromatic light such as laser exposure, there is a large difference in the photocuring degree between the front surface and the back surface of the exposed surface. For this reason, in order to obtain sufficient tenting in a monochromatic light exposure film such as laser exposure, it is necessary to cure the back surface of the exposure surface firmly. To that end, the absorbance of the film must be lowered. It is important that the light is sufficiently transmitted to the back surface to cause curing.

It is a schematic diagram which shows one Embodiment of the photosensitive element which concerns on this invention. It is a schematic diagram which shows one process example of the manufacturing method of the photoresist pattern which concerns on this invention. It is a schematic diagram which shows one process example (subtractive method using etching) of the manufacturing method of the printed wiring board which concerns on this invention. It is a schematic diagram which shows one process example (semi-additive method using plating) of the manufacturing method of the printed wiring board which concerns on this invention. It is a chart of FT-IR by ATR method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Photosensitive element, 11 ... Support body, 12 ... Photosensitive resin composition layer, 2 ... Board | substrate (circuit formation board | substrate), 121 ... Photoresist pattern, 21 ... Processed layer, 211 ... Circuit, 4 ... Printed wiring Board.

Claims (9)

(A) Binder polymer, (B) Photopolymerizability having at least one ethylenically unsaturated group per molecule, comprising as an essential component a photopolymerizable compound having at least 3 ethylenically unsaturated groups per molecule. A photosensitive resin composition containing a compound and (C) a hexaarylbisimidazole compound and (C2) a hydrogen donor as (C) a photopolymerization initiator, the characteristics shown in the following (a) to (c) A photosensitive resin composition having:
(A) The photosensitive resin composition layer coated using the photosensitive resin composition exhibits an absorbance of 0.2 to 0.8 with respect to monochromatic light used for exposure in the range of 340 to 410 nm.
(B) The photosensitive resin composition layer formed on the substrate is exposed to the monochromatic light and then developed with a developing solution, and the photoresist pattern has an aspect ratio of 0.7 or more.
(C) After forming the photosensitive resin composition layer on a substrate having 24 holes with a diameter of 6 mm and exposing with a light exposure amount of 20 steps after development of the 41-step tablet, exposure is performed. When the development process is performed three times, the hole breakage rate is 10% or less.   The photosensitive resin according to claim 1, wherein the photosensitive resin composition layer coated with the photosensitive resin composition exhibits an absorbance of 0.3 to 0.6 for monochromatic light used for exposure in a range of 340 to 410 nm. Resin composition. The photosensitive resin composition according to claim 1 or 2, comprising (C3) a diaminobenzophenone compound represented by (1) or a coumarin compound represented by formula (2).

  The blending amount of the component (A) and the component (B) is 40 to 80 parts by weight of the component (A) and 20 to 20 parts of the component (B) with respect to 100 parts by weight of the total amount of the component (A) and the component (B). It is 60 weight part, The photosensitive resin composition of any one of Claims 1-3 characterized by the above-mentioned.   The blending amount of (C) is 0.1 to 20 parts by weight with respect to 100 parts by weight of the total amount of component (A) and component (B). The photosensitive resin composition as described. (A) Binder polymer, (B) Photopolymerizability having at least one ethylenically unsaturated group per molecule, comprising as an essential component a photopolymerizable compound having at least 3 ethylenically unsaturated groups per molecule. A photosensitive element formed by coating and drying a photosensitive resin composition containing a compound and (C) a hexaarylbisimidazole compound and (C2) a hydrogen donor as a photopolymerization initiator on a support. A photosensitive element having the following characteristics (a) to (c):
(A) The photosensitive resin composition layer of the photosensitive element exhibits an absorbance of 0.2 to 0.8 for monochromatic light used for exposure in the range of 340 to 410 nm.
(B) The photosensitive resin composition layer formed on the substrate using the photosensitive element is exposed to the monochromatic light, and then developed with a developer, and the photoresist pattern has an aspect ratio of 0. 7 or more.
(C) After forming the photosensitive resin composition layer on a substrate having 24 holes with a diameter of 6 mm and exposing with a light exposure amount of 20 steps after development of the 41-step tablet, exposure is performed. When the development process is performed three times, the hole breakage rate is 10% or less.   The photosensitive element of Claim 6 formed by laminating | stacking a protective film so that the photosensitive resin composition layer may be contact | connected. (A) Binder polymer, (B) Photopolymerizability having at least one ethylenically unsaturated group per molecule, comprising as an essential component a photopolymerizable compound having at least 3 ethylenically unsaturated groups per molecule. The photosensitive resin composition having the characteristics shown in the following (a) to (c), including the compound and (C) a hexaarylbisimidazole compound and (C2) a hydrogen donor as a photopolymerization initiator (C) A method for producing a photoresist pattern, comprising forming a photosensitive resin composition layer on a substrate, followed by scanning exposure with an ultraviolet laser and a development step.
(A) The photosensitive resin composition layer coated using the photosensitive resin composition exhibits an absorbance of 0.2 to 0.8 with respect to monochromatic light used for exposure in the range of 340 to 410 nm.
(B) The photosensitive resin composition layer formed on the substrate is exposed to the monochromatic light and then developed with a developing solution, and the photoresist pattern has an aspect ratio of 0.7 or more.
(C) After forming the photosensitive resin composition layer on a substrate having 24 holes with a diameter of 6 mm and exposing with a light exposure amount of 20 steps after development of the 41-step tablet, exposure is performed. When the development process is performed three times, the hole breakage rate is 10% or less. (A) Binder polymer, (B) Photopolymerizability having at least one ethylenically unsaturated group per molecule, comprising as an essential component a photopolymerizable compound having at least 3 ethylenically unsaturated groups per molecule. The photosensitive resin composition having the characteristics shown in the following (a) to (c), including the compound and (C) a hexaarylbisimidazole compound and (C2) a hydrogen donor as a photopolymerization initiator (C) Then, after forming a photosensitive resin composition layer on the substrate, scanning exposure with an ultraviolet laser, and forming a photoresist pattern through a development process, the layer to be processed on the substrate is selectively etched, or the layer to be processed on the substrate A method for producing a printed wiring board, characterized by selectively plating a substrate.
(A) The photosensitive resin composition layer coated using the photosensitive resin composition exhibits an absorbance of 0.2 to 0.8 with respect to monochromatic light used for exposure in the range of 340 to 410 nm.
(B) The photosensitive resin composition layer formed on the substrate is exposed to the monochromatic light and then developed with a developing solution, and the photoresist pattern has an aspect ratio of 0.7 or more.
(C) After forming the photosensitive resin composition layer on a substrate having 24 holes with a diameter of 6 mm and exposing with a light exposure amount of 20 steps after development of the 41-step tablet, exposure is performed. When the development process is performed three times, the hole breakage rate is 10% or less.

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