JP5600903B2 - Photosensitive resin composition, photosensitive element using the same, resist pattern forming method, and printed wiring board manufacturing method - Google Patents

Description

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

  A photosensitive resin composition is widely used as a material for forming a resist pattern of a printed wiring board. The photosensitive resin composition is used as a photosensitive element including a support film and a layer (hereinafter referred to as “photosensitive resin layer”) formed using the photosensitive resin composition formed on the support film. It is often done.

  The resist pattern of the printed wiring board is formed as follows, for example. First, the photosensitive resin layer of the photosensitive element is laminated (laminated) on the substrate. Next, after peeling off and removing the support film, the predetermined portion of the photosensitive resin layer is irradiated with actinic rays to expose and cure the predetermined portion. Thereafter, a portion other than the predetermined portion (unexposed / uncured portion) is removed (developed) from the substrate, whereby a resist pattern made of a cured product of the photosensitive resin composition is formed on the substrate.

  As the exposure method, conventionally, a method of exposing through a photomask using a mercury lamp as a light source is known, but in recent years, an exposure method called DLP (Digital Light Processing) has also been proposed ( For example, refer nonpatent literature 1). DLP is a method of directly drawing digital data of an exposure pattern on a photosensitive resin layer (hereinafter referred to as “direct drawing exposure method”).

  The direct drawing exposure method is being introduced into the production of high-density package substrates and the like in order to enable highly accurate pattern formation. However, since the direct drawing exposure method tends to require a longer exposure time than the conventional method, it is not desirable in terms of production efficiency. In order to shorten the exposure time and increase the production efficiency, it is necessary to improve the sensitivity of the photosensitive resin composition.

  In addition, with the recent increase in the density of package substrates, there is an increasing demand for a photosensitive resin composition that forms a good resist shape (resist pattern cross-sectional shape). Specifically, when the resist shape is trapezoidal or inverted trapezoidal, or when there is a tailing of the resist, short circuits and disconnections may occur in the formed circuit, and the resist shape should be rectangular. Is desirable.

  Furthermore, the photosensitive resin composition for forming a resist pattern is desired to have excellent peeling characteristics after curing. That is, it is desired that the cured product (resist) has a short stripping time and a small strip size. By shortening the peeling time as described above, the resist pattern forming efficiency is improved, and by reducing the size of the peeling piece, the resist peeling residue is reduced and the yield of resist pattern formation is improved.

  Other properties required for the photosensitive resin composition for forming a resist pattern include resolution (removal accuracy of unexposed portions) and adhesion to a substrate (developer resistance of exposed portions).

  Here, Patent Document 1 discloses a photosensitive resin composition using a specific binder polymer, a sensitizing dye, or the like as a photosensitive resin composition having good sensitivity that can be applied to a direct drawing exposure method. Yes.

  Patent Documents 2 to 4 disclose photosensitive resin compositions in which a polyfunctional acrylate compound is introduced to increase the number of crosslinking points in order to improve adhesion (developer resistance).

  Patent Document 5 discloses a photosensitive resin composition using a polymerization inhibitor such as catechol or hydroquinone in order to improve the contrast (imaging property) between an exposed portion and an unexposed portion.

  Patent Document 6 discloses a photosensitive resin composition using a specific binder polymer, a pyrazoline compound, or the like in order to improve the resolution.

JP 2005-122123 A JP 2003-215799 A JP 2003-215797 A JP 2003-202667 A JP 2000-162767 A JP 2007-101941 A

“Electronic Packaging Technology”, June 2002, p. 74-79

  However, although the photosensitive resin composition of Patent Document 1 is good in terms of sensitivity and peeling characteristics, it is not necessarily sufficient in terms of resolution and adhesion.

  Although the photosensitive resin composition of patent documents 2-4 has favorable adhesiveness, it is not enough at the point of peeling characteristics, and there exists a tendency for hardened | cured material to be hard to peel and remove from a board | substrate.

  The photosensitive resin composition of Patent Document 5 is good in terms of resolution, adhesion, and imaging properties, but is not sufficient in terms of sensitivity, and requires a lot of exposure time when using a direct drawing exposure method.

  Although the photosensitive resin composition of Patent Document 6 is good in terms of resolution, it is not necessarily sufficient in terms of resist shape and peeling characteristics after curing.

  As described above, none of the conventional photosensitive resin compositions sufficiently satisfy the characteristics required for the photosensitive resin composition for forming a resist pattern.

  Accordingly, the present invention provides a photosensitive resin composition having good sensitivity, resolution, adhesion, resist shape, and release characteristics after curing, a photosensitive element using the same, a method for forming a resist pattern, and printed wiring It aims at providing the manufacturing method of a board.

  As a result of intensive studies to solve the above problems, the present inventors can obtain a photosensitive resin composition satisfying any of the above characteristics by using a photopolymerizable compound having a specific structure. As a result, the present invention has been completed.

  That is, the present invention is a photosensitive resin composition containing (A) a binder polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator, and (B) the photopolymerizable compound is represented by the following general formula: It is the photosensitive resin composition containing the compound represented by Formula (1). By providing such a configuration, the photosensitive resin composition of the present invention has good sensitivity, resolution, adhesion, resist shape and release characteristics after curing.

  In the general formula (1), each R1 independently represents a hydrogen atom or a methyl group, each X independently represents a divalent organic group, each Y independently represents a monovalent organic group, and m represents 0. An integer of -4 is shown, and n is an integer of 0-10.

  Among the compounds represented by the general formula (1), those having a bonding position on the aromatic ring are preferred, such as the compounds represented by the following general formula (1-1). The symbol in the following general formula (1-1) means the same as the above general formula (1).

From the viewpoint of further improving the effects of the present invention, the compound represented by the general formula (1) preferably includes a compound represented by the following general formula (2).

  In the general formula (2), each R1 independently represents a hydrogen atom or a methyl group, each X independently represents a divalent organic group, and each R2 independently represents a hydrogen atom, a phenyl group, or one carbon atom. 10 represents an alkyl group or a cycloalkyl group, and n represents an integer of 0 to 10.

  Among the compounds represented by the general formula (2), those having a bonding position on the aromatic ring like the compounds represented by the following general formula (2-1) are preferable. The symbol in the following general formula (2-1) means the same as the above general formula (2).

  The (C) photopolymerization initiator preferably contains a hexaarylbiimidazole derivative from the viewpoint of improving sensitivity and adhesion.

  The photosensitive resin composition preferably contains (D) a sensitizing dye from the viewpoint of improving sensitivity, resolution, and adhesion.

  The photosensitive resin composition preferably contains (E) an amine compound from the viewpoint of improving sensitivity.

  Moreover, this invention relates to the photosensitive element provided with a support film and the photosensitive resin layer formed using the said photosensitive resin composition formed on this support film.

  In addition, the present invention provides a laminating step of laminating a photosensitive resin layer formed using the photosensitive resin composition on a substrate, and irradiating a predetermined portion of the photosensitive resin layer with actinic rays to the predetermined portion. A resist pattern comprising a cured product of the photosensitive resin composition on the substrate by removing a portion other than the predetermined portion of the photosensitive resin layer from the substrate by exposing and curing the photosensitive resin layer. And a developing process for forming a resist pattern.

  In the exposure step, it is preferable that the predetermined portion is exposed and cured by directly irradiating the photosensitive resin layer with a laser beam having a predetermined pattern. According to such a direct drawing exposure method, a highly accurate pattern can be formed.

  Furthermore, this invention relates to the manufacturing method of a printed wiring board including etching or plating the board | substrate with which the resist pattern was formed by the said method.

  According to the present invention, a photosensitive resin composition having good sensitivity, resolution, adhesion, resist shape, and release property after curing, a photosensitive element using the same, a method for forming a resist pattern, and printed wiring A method for manufacturing a plate can be provided.

It is an end view which shows one Embodiment of the photosensitive element of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings as necessary. However, the present invention is not limited to the following embodiments. In addition, the dimensional ratio of drawing is not restricted to the ratio of illustration. In this specification, (meth) acrylic acid means acrylic acid or methacrylic acid, (meth) acrylate means acrylate or methacrylate, and (meth) acryloyl group means acryloyl group or methacryloyl. Means a group.

(Photosensitive resin composition)
The photosensitive resin composition of the present embodiment includes (A) a binder polymer (hereinafter also referred to as “(A) component”), (B) a photopolymerizable compound (hereinafter also referred to as “(B) component”). And (C) a photopolymerization initiator (hereinafter also referred to as “component (C)”).

<(B) component: photopolymerizable compound>
The photopolymerizable compound as the component (B) includes a compound represented by the following general formula (1).

  In the general formula (1), each R1 independently represents a hydrogen atom or a methyl group, each X independently represents a divalent organic group, each Y independently represents a monovalent organic group, and m represents 0. An integer of -4 is shown, and n is an integer of 0-10.

  The monovalent organic group represented by Y is not particularly limited, and may be a linear or branched alkyl group having 1 to 5 carbon atoms, an alkoxy group, a hydroxyalkyl group, or the like, or a hydroxyl group.

The compound represented by the general formula (1) preferably includes a compound represented by the following general formula (2).

  In the general formula (2), each R1 independently represents a hydrogen atom or a methyl group, each X independently represents a divalent organic group, and each R2 independently represents a hydrogen atom, a phenyl group, or one carbon atom. 10 represents a linear or branched alkyl group or cycloalkyl group, and n represents an integer of 0 to 10.

The compound represented by the general formula (2) may also include a compound represented by the following general formula (3).

  In the compound represented by the general formula (3), R2s of the general formula (2) are bonded to each other to form an alicyclic structure. In the general formula (3), Z represents a linear or branched alkylene group having 2 to 10 carbon atoms.

  The divalent organic group represented by X in the general formula (1), (2) or (3) is not particularly limited, and includes a phenylene chain, a linear or branched (poly) alkylene chain, a cyclo Examples include an alkylene chain or a (poly) oxyalkylene chain, an ester bond, an amide bond, a urethane bond, or an acetal bond.

  Examples of the (poly) alkylene chain include a methylene chain, an ethylene chain, a trimethylene chain, a tetramethylene chain, a pentamethylene chain, a hexamethylene chain, a heptamethylene chain, an octamethylene chain, a nonamethylene chain, and a decamethylene chain. Examples of the cycloalkylene chain include those having a structure such as cyclohexane, cycloheptane, and cyclooctane.

  As the (poly) oxyalkylene chain, those having both a (poly) oxyethylene chain and a (poly) oxypropylene chain ((poly) oxy-n-propylene chain or (poly) oxyisopropylene chain) are preferable. In addition, (poly) oxy-n-butylene chain, (poly) oxyisobutylene chain, (poly) oxy-n-pentylene chain, (poly) oxyhexylene chain, and the structural isomers thereof have 4 carbon atoms. A (poly) oxyalkylene chain of about -10 is mentioned. Each of the (poly) oxyethylene chain and the (poly) oxypropylene chain may be continuously present in blocks or randomly. In the (poly) oxyisopropylene chain, the secondary carbon of the propylene group may be bonded to an oxygen atom, or the primary carbon may be bonded to an oxygen atom.

  As a method for obtaining a compound having an ester bond, an amide bond, a urethane bond or an acetal bond, a phenol novolac type epoxy compound, a cresol novolak type epoxy compound, a bisphenol A type phenol novolak type epoxy compound, a bisphenol F type phenol novolak type epoxy compound, etc. (Meth) acrylic acid ester having a vinyl ether group, an isocyanate group or an epoxy group is added to the phenolic OH group. Moreover, the method of adding the (meth) acrylic acid ester which has a vinyl ether group or an epoxy group to the carboxylic acid produced after adding an acid anhydride to the said phenolic OH group is mentioned. Furthermore, a method of adding (meth) acrylic acid or a (meth) acrylic acid ester having an OH group to the epoxy-modified structure of the phenolic OH group, or an OH group of the epoxy-modified structure ( The method of adding the carboxylic acid produced by the addition reaction of a (meth) acrylic acid ester and an acid anhydride is mentioned.

  As the organic group represented by [CH2 = C (R1) COO-X-] in the compound represented by the above general formula (1), (2) or (3) obtained by the above method, the following formula (a ) To (o).

  The molecular weight of the compound represented by the general formula (1) is preferably 300 to 4000, more preferably 400 to 3500, and more preferably 500 to 2800 from the viewpoints of sensitivity, resolution, and plating resistance. It is particularly preferred.

  The content of the compound represented by the general formula (1) is 1 to 15 parts by mass with respect to 100 parts by mass of the total amount of the component (A) (binder polymer) and the component (B) (photopolymerizable compound). It is preferable that the content is 5 to 15 parts by mass. If this content is less than 1 part by mass, sufficient sensitivity and resolution tend to be difficult to obtain, and if it exceeds 15 parts by mass, it tends to be difficult to form a film and a good resist shape is obtained. There is a tendency to become difficult.

  In the photosensitive resin composition of the present embodiment, as the component (B) (photopolymerizable compound), a photopolymerizable unsaturated compound having one polymerizable ethylenically unsaturated bond in the molecule (hereinafter referred to as “(B ') Component')) and a photopolymerizable unsaturated compound having two or more polymerizable ethylenically unsaturated bonds in the molecule (hereinafter referred to as "component (B") ") It is preferable from the viewpoint of obtaining the effect of the present invention more reliably.

  Examples of the component (B ′) (photopolymerizable unsaturated compound having one polymerizable ethylenically unsaturated bond in the molecule) include phthalic acid compounds represented by the following general formula (4).

  In the general formula (4), R3 represents a hydrogen atom or a methyl group, R4 represents a hydrogen atom, a methyl group or a halogenated methyl group, and Q represents a halogen atom, a hydroxyl group or an alkyl group having 1 to 6 carbon atoms. K represents an integer of 0 to 4. Note that when k is an integer of 2 or more, a plurality of Qs may be the same or different.

  Examples of the phthalic acid compound represented by the general formula (4) include γ-chloro-β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate, β-hydroxyalkyl-β ′-(meta ) Acryloloxyalkyl-o-phthalate and the like. These may be used alone or in combination of two or more. The above γ-chloro-β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate is commercially available as “FA-MECH” (trade name, manufactured by Hitachi Chemical Co., Ltd.). .

  Other examples of the component (B ′) (photopolymerizable unsaturated compound having one polymerizable ethylenically unsaturated bond in the molecule) include nonylphenoxypolyethyleneoxyacrylate and alkyl (meth) acrylate. .

  Nonylphenoxypolyethyleneoxyacrylate includes nonylphenoxytetraethyleneoxyacrylate, nonylphenoxypentaethyleneoxyacrylate, nonylphenoxyhexaethyleneoxyacrylate, nonylphenoxyheptaethyleneoxyacrylate, nonylphenoxyoctaethyleneoxyacrylate, nonylphenoxynonaethyleneoxyacrylate, Nonylphenoxydecaethyleneoxyacrylate, nonylphenoxyundecaethyleneoxyacrylate, etc. are mentioned. These may be used alone or in combination of two or more.

  Among these components (B ′), from the viewpoint of shortening the resist stripping time, it is preferable to use the phthalic acid compound represented by the above general formula (4) or nonylphenoxypolyethyleneoxyacrylate. From the viewpoint of improvement, it is particularly preferable to use the phthalic acid compound represented by the general formula (4).

  The content of the component (B ′) is preferably 1 to 15 parts by mass, and more preferably 2 to 10 parts by mass with respect to 100 parts by mass of the total amount of the components (A) and (B). If this content exceeds 15 parts by mass, the resolution and adhesion tend to decrease.

On the other hand, as the component (B ″) (photopolymerizable unsaturated compound having two or more polymerizable ethylenically unsaturated bonds in the molecule), in addition to the compound represented by the general formula (1) And a bisphenol A-based (meth) acrylate compound represented by the following general formula (5).

  In the general formula (5), R5 independently represents a hydrogen atom or a methyl group, AO, BO, OD and OG each independently represent an oxyalkylene group having 1 to 6 carbon atoms, p, q, r And s each independently represents an integer of 0 to 20, and the sum of p, q, r and s is an integer of 0 to 40.

  Examples of the bisphenol A-based (meth) acrylate compound represented by the general formula (5) include 2,2-bis (4-((meth) acryloxyethoxy) phenyl) propane, 2,2-bis (4- ( (Meth) acryloxypolyethoxy) phenyl) propane, 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.

  Examples of the 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane include 2,2-bis (4-((meth) acryloxydiethoxy) phenyl) propane and 2,2-bis. (4-((meth) acryloxytriethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxytetraethoxy) phenyl) propane, 2,2-bis (4-((meth) acrylic) Loxypentaethoxy) 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) acryloxynononaethoxy) Enyl) 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) acryloxyhexadeca) And ethoxy) phenyl) propane.

  Of these, 2,2-bis (4- (methacryloxyethoxy) phenyl) propane (EO 2.6 mol) is commercially available as “BPE-100” (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.). 2,2-bis (4- (methacryloxypentaethoxy) phenyl) propane is “BPE-500” (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.) or “FA-321M” (Hitachi Chemical). It is commercially available as a trade name, manufactured by Kogyo Co., Ltd., and 2,2-bis (4- (methacryloxypentadecaethoxy) phenyl) propane is “BPE-1300” (Shin Nakamura Chemical Co., Ltd.) ), Product name) and commercially available.

  From the viewpoint of the flexibility, resolution and adhesion of the cured product, the compound represented by the general formula (5) contains a compound in which the sum of p, q, r and s is an integer of 4 to 40. It is preferable. The total is more preferably an integer of 4 to 20, and further preferably an integer of 8 to 15.

  When the compound represented by the general formula (5) includes a compound in which the sum of p, q, r, and s is an integer of 4 to 40, the content thereof is (A) component (binder polymer) and It is preferable that it is 1-20 mass parts with respect to 100 mass parts of total amounts of (B) component (photopolymerizable compound), and it is more preferable that it is 5-15 mass parts.

  Among the compounds represented by the general formula (5), as a compound in which the sum of p, q, r and s is an integer of 4 to 40, 2,2-bis (4- (methacryloxypentaethoxy) phenyl ) Propane, 2,2-bis (4- (methacryloxypentadecaethoxy) phenyl) propane, and the like.

  From the viewpoint of improving resolution, adhesion and peelability, the compound represented by the general formula (5) may contain a compound in which the sum of p, q, r and s is an integer of 1 to 3. preferable. When such a compound is contained, the content is preferably 1 to 15 parts by mass, and 5 to 15 parts by mass with respect to 100 parts by mass of the total amount of component (A) and component (B). Is more preferable. When this content exceeds 20 parts by mass, the resist pattern tends to be chipped.

  Among the compounds represented by the general formula (5), the compound in which the sum of p, q, r and s is an integer of 1 to 3 is 2,2-bis (4- (methacryloxyethoxy) phenyl). Propane is mentioned.

  In addition, as the component (B ″) (photopolymerizable unsaturated compound having two or more polymerizable ethylenically unsaturated bonds in the molecule), α, β-unsaturated carboxylic acid is reacted with polyhydric alcohol. And a compound obtained by reacting a glycidyl group-containing compound with an α, β-unsaturated carboxylic acid, a urethane monomer such as a (meth) acrylate compound having a urethane bond in the molecule, and the like. These may be used alone or in combination of two or more.

  Examples of the compound obtained by reacting the polyhydric alcohol with an α, β-unsaturated carboxylic acid include polyethylene glycol di (meth) acrylate having 2 to 14 ethylene groups and 2 to 14 propylene groups. Polypropylene glycol di (meth) acrylates such as polyethylene / polypropylene glycol di (meth) acrylates having 2 to 14 ethylene groups and 2 to 14 propylene groups, Trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, EO modified trimethylolpropane tri (meth) acrylate, PO modified trimethylolpropane tri (meth) acrylate, EO, PO modified trimethylolpropane tri (meta) A) Examples thereof include acrylate, tetramethylolmethane tri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, and dipentaerythritol hexa (meth) acrylate. These may be used alone or in combination of two or more.

  Among these, EO-modified trimethylolpropane trimethacrylate is commercially available as “TMPT21” (trade name, manufactured by Hitachi Chemical Co., Ltd.). “EO-modified” means a compound having an oxyethylene group block structure (polyoxyethylenated compound), and “PO-modified” means a compound having an oxypropylene group block structure. It means that it is a (polyoxypropylenated compound).

  As the (meth) acrylate compound having a urethane bond in the molecule, 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. Is mentioned. These may be used alone or in combination of two or more.

  Of these, EO-modified urethane di (meth) acrylate is commercially available as “UA-11” (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.), and EO, PO-modified urethane di (meth) acrylate is , "UA-13" (manufactured by Shin-Nakamura Chemical Co., Ltd., product name).

  Among these (B ″) components, it is preferable to use a bisphenol A (meth) acrylate compound represented by the general formula (5) from the viewpoint of improving sensitivity, resolution, and adhesion. From the viewpoint of improving the flexibility of the cured product (cured film) of the photosensitive resin composition, among the compounds obtained by reacting the polyhydric alcohol with an α, β-unsaturated carboxylic acid, It is preferable to use a polyalkylene glycol di (meth) acrylate having a (poly) oxyethylene chain and a (poly) oxypropylene chain.

  As said polyalkylene glycol di (meth) acrylate, (poly) oxyethylene chain and (poly) oxypropylene chain ((poly) oxy-n-propylene chain or (poly) There is no particular limitation as long as it has any of) oxyisopropylene chain). In addition, the polyalkylene glycol di (meth) acrylate further includes (poly) oxy-n-butylene chain, (poly) oxyisobutylene chain, (poly) oxy-n-pentylene chain, (poly) oxyhexylene chain, These may have a (poly) oxyalkylene chain having about 4 to 6 carbon atoms, which is a structural isomer or the like.

  In the molecule of polyalkylene glycol di (meth) acrylate, the (poly) oxyethylene chain and the (poly) oxypropylene chain may be continuously present in blocks or randomly. In the (poly) oxyisopropylene chain, the secondary carbon of the propylene group may be bonded to an oxygen atom, or the primary carbon may be bonded to an oxygen atom.

  Examples of such polyalkylene glycol di (meth) acrylates include compounds represented by the following general formula (6a), (6b) or (6c). These may be used alone or in combination of two or more.

  In the above formulas (6a), (6b) and (6c), R6 independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. E represents an ethylene group, and P represents a propylene group. EO represents an oxyethylene group, and PO represents an oxypropylene group. m1, m2, m3 and m4 represent the number of repeating structural units composed of oxyethylene groups, n1, n2, n3 and n4 represent the number of repeating structural units composed of oxypropylene groups, each independently an integer of 1 to 30 Indicates. Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group.

  In the compound represented by the general formula (6a), (6b) or (6c), the total number of repeating units (m1 + m2, m3 or m4) of the structural unit (EO: oxyethylene group) of the (poly) oxyethylene chain is It is an integer of 1-30, Preferably it is an integer of 1-10, More preferably, it is an integer of 4-9, Most preferably, it is an integer of 5-8. If the total number of repetitions exceeds 30, sufficient tent reliability and resist shape tend to be difficult to obtain.

  The total number (n1, n2 + n3 or n4) of the number of repeating units (PO: oxypropylene group) of the (poly) oxypropylene chain is an integer of 1-30, preferably an integer of 5-20, more preferably It is an integer of 8 to 16, particularly preferably an integer of 10 to 14. When the total number of repetitions exceeds 30, it is difficult to obtain a sufficient resolution and sludge tends to be generated.

  As the compound represented by the general formula (6a), a vinyl compound in which R6 = methyl group, m1 + m2 = 6 (average value), and n1 = 12 (average value) (trade name FA, manufactured by Hitachi Chemical Co., Ltd.) -023M) and the like. The compound represented by the general formula (6b) is a vinyl compound (trade name FA manufactured by Hitachi Chemical Co., Ltd.) where R6 = methyl group, m3 = 6 (average value), and n2 + n3 = 12 (average value). -024M) and the like. As a compound represented by the general formula (6c), a vinyl compound (made by Shin-Nakamura Chemical Co., Ltd., sample name) in which R6 = hydrogen atom, m4 = 1 (average value), and n4 = 9 (average value) is used. NK ester HEMA-9P) and the like. These may be used alone or in combination of two or more.

  (B ′) component (photopolymerizable unsaturated compound having one polymerizable ethylenically unsaturated bond in the molecule) and (B ″) component (two or more polymerizable ethylenically unsaturated groups in the molecule) When using in combination with a photopolymerizable unsaturated compound having a saturated bond), the content ratio is (B ′) / (B ″) in terms of sensitivity, resolution, adhesion, peelability and resist shape. 5-30 / 95-70, preferably 10-25 / 90-75.

  The content of the component (B) (photopolymerizable compound) is preferably 30 to 70 parts by mass with respect to 100 parts by mass of the total amount of the component (A) (binder polymer) and the component (B). It is more preferable to set it as a mass part, and it is especially preferable to set it as 40-60 mass parts. When this content is less than 30 parts by mass, sufficient sensitivity and resolution tend to be difficult to obtain, and when it exceeds 70 parts by mass, it tends to be difficult to form a film and a good resist shape is obtained. There is a tendency to become difficult.

<(A) component: Binder polymer>
Examples of the (A) component binder polymer include acrylic resins, styrene resins, epoxy resins, amide resins, amide epoxy resins, alkyd resins, and phenol resins. These may be used alone or in combination of two or more. Among these, acrylic resins are preferable from the viewpoint of alkali developability and flexibility.

  The acrylic resin can be produced, for example, by radical polymerization of a polymerizable monomer (monomer). Examples of the polymerizable monomer include styrene; a polymerizable styrene derivative substituted at the α-position or aromatic ring such as α-methylstyrene and vinyltoluene; acrylamide such as diacetone acrylamide; acrylonitrile; vinyl-n- Ethers of vinyl alcohol such as butyl ether; (meth) acrylic acid alkyl ester, (meth) acrylic acid benzyl ester, (meth) acrylic acid cyclohexyl ester, (meth) acrylic acid phenoxyethyl ester, (meth) acrylic acid tetrahydrofurfuryl (Meth) acrylic acid esters such as esters, (meth) acrylic acid dimethylaminoethyl ester, (meth) acrylic acid diethylaminoethyl ester, (meth) acrylic acid glycidyl ester; 2,2,2-trifluoroethyl (meth) Acrylates, acrylates such as 2,2,3,3-tetrafluoropropyl (meth) acrylate; (meth) acrylic acid, α-bromo (meth) acrylic acid, α-chloro (meth) acrylic acid, β-furyl (meth) ) Acrylic acid, acrylic acid such as β-styryl (meth) acrylic acid; maleic acid; maleic anhydride; maleic acid monoesters such as monomethyl maleate, monoethyl maleate, monoisopropyl maleate; fumaric acid, cinnamic acid And acids such as α-cyanocinnamic acid, itaconic acid, crotonic acid, propiolic acid and the like. These may be used alone or in combination of two or more.

  As said (meth) acrylic-acid alkylester, the compound represented by following General formula (7) is mentioned.

In the general formula (7), R7 represents a hydrogen atom or a methyl group, and R8 represents an alkyl group having 1 to 12 carbon atoms.

  Examples of the alkyl group having 1 to 12 carbon atoms represented by R8 in the general formula (7) include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, and nonyl group. Decyl group, undecyl group, dodecyl group, and structural isomers thereof. From the viewpoint of further improving sensitivity and peeling properties, the alkyl group is preferably one having 4 or less carbon atoms. The alkyl group may be substituted with a hydroxyl group, an epoxy group, a halogen group, or the like.

  Examples of the compound (monomer) represented by the general formula (7) include (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid propyl ester, (meth) acrylic acid butyl ester, ( (Meth) acrylic acid pentyl ester, (meth) acrylic acid hexyl ester, (meth) acrylic acid heptyl ester, (meth) acrylic acid octyl ester, (meth) acrylic acid 2-ethylhexyl ester, (meth) acrylic acid nonyl ester, ( Examples include meth) acrylic acid decyl ester, (meth) acrylic acid undecyl ester, (meth) acrylic acid dodecyl ester, and the like. These may be used alone or in combination of two or more.

  From the viewpoint of alkali developability, the (A) binder polymer preferably has a carboxyl group. 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, (meth) acrylic acid is preferable, and methacrylic acid is more preferable.

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

  Further, from the viewpoint of adhesion and release characteristics, the (A) binder polymer preferably contains styrene or a styrene derivative as a polymerizable monomer. The content of the above styrene or styrene derivative as a copolymerization component (the ratio of styrene or styrene derivative to the total polymerizable monomer used) is 10 to 10 from the viewpoint of improving both adhesion and release characteristics. It is preferably 70% by mass, more preferably 20 to 65% by mass, and particularly preferably 30 to 50% by mass.

  From the standpoint of improving resolution, adhesion, resist shape, and release characteristics, (A) the binder polymer is a polymerizable monomer of (meth) acrylic acid benzyl ester or (meth) acrylic acid t-butyl ester. It is preferable to contain as a body.

  Content when the above (meth) acrylic acid benzyl ester or (meth) acrylic acid t-butyl ester is used as a copolymerization component ((meth) acrylic acid benzyl ester or (meth) relative to all polymerizable monomers used) The ratio of the acrylic acid t-butyl ester) is preferably 10 to 50% by mass, and preferably 15 to 45% by mass from the viewpoint of improving the resolution, adhesion, resist shape and release characteristics. More preferably, it is 20-40 mass%, and it is especially preferable.

  (A) As a binder polymer, one type of binder polymer may be used alone, or two or more types of binder polymers may be used in combination. When two or more types of binder polymers are used in combination, the two or more types of binder polymers may be dispersed regardless of whether the copolymerization component (repeating unit) is different or the weight average molecular weight is different. Different degrees may be used. A polymer having a multimode molecular weight distribution described in JP-A-11-327137 can also be used.

  (A) The weight average molecular weight (Mw) and number average molecular weight (Mn) of a binder polymer can be measured by gel permeation chromatography (GPC) (converted by a calibration curve using standard polystyrene).

  According to this measurement method, the weight average molecular weight (Mw) of the (A) binder polymer is usually 5,000 to 300,000, preferably 10,000 to 200,000, more preferably 15,000 to 80,000, and 20,000 to 70000. It is more preferable that it is 25000-60000. If Mw is less than 5000, the developer resistance tends to be insufficient, and if it exceeds 300,000, the development time tends to be longer.

  (A) The dispersion degree (Mw / Mn) of the binder polymer is preferably 1.0 to 3.0, and more preferably 1.0 to 2.0. If the degree of dispersion exceeds 3.0, the adhesion and resolution tend not to be obtained sufficiently.

  (A) The acid value of the binder polymer is preferably 100 to 300 mgKOH / g, more preferably 110 to 250 mgKOH / g, still more preferably 120 to 230 mgKOH / g, and 140 to 220 mgKOH / g. It is particularly preferable that it is 150 to 210 mgKOH / g. If the acid value is less than 30 mg KOH / g, the development time tends to be long, and if it exceeds 300 mg KOH / g, the developing solution resistance of the photocured resist tends to be insufficient. In addition, when performing solvent image development as a image development process, it is preferable to prepare the polymerizable monomer which has a carboxyl group in a small quantity.

  (A) The binder polymer may have a characteristic group having photosensitivity in the molecule as necessary.

  The content of the (A) binder polymer is preferably 30 to 70 parts by mass, more preferably 35 to 65 parts by mass, based on 100 parts by mass of the total amount of the components (A) and (B). Preferably, the amount is 40 to 60 parts by mass. If this content is less than 30 parts by mass, a sufficiently good resist shape tends to be not obtained, and if it exceeds 70 parts by mass, sufficiently good sensitivity and resolution tend not to be obtained.

<(C) Photopolymerization initiator>
As the photopolymerization initiator which is component (C), 4,4′-bis (diethylamino) benzophenone, benzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, 2- Aromatic ketones such as methyl-1- [4- (methylthio) phenyl] -2-morpholino-propanone-1; quinones such as alkylanthraquinones; benzoin ether compounds such as benzoin alkyl ether; benzoin compounds such as benzoin and alkylbenzoin 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-diphenyl 2,4,5 such as ruimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer -Triarylimidazole dimer; acridine derivatives such as 9-phenylacridine, 1,7-bis (9,9'-acridinyl) heptane, and the like. These may be used alone or in combination of two or more.

  Among these, from the viewpoint of adhesion and sensitivity, the (C) photopolymerization initiator preferably contains a 2,4,5-triarylimidazole dimer (hexaarylbiimidazole derivative). The aryl group substituents of two 2,4,5-triarylimidazoles may give the same and symmetrical compounds, or differently give asymmetric compounds.

  Among the hexaarylbiimidazole derivatives, 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenylbisimidazole is commercially available as “BCIM” (trade name, manufactured by Hampford). Are available.

  (C) As content of a photoinitiator, it is preferable to set it as 0.1-10 mass parts on the basis of 100 mass parts of total amounts of (A) component and (B) component, 2-6 mass parts It is more preferable to set it as 3.5 to 5 mass parts. If the content is less than 0.1 parts by mass, sufficiently good sensitivity and resolution tend not to be obtained, and if it exceeds 10 parts by mass, a sufficiently good resist shape tends to be not obtained.

<(D) component: sensitizing dye>
Furthermore, it is preferable that the photosensitive resin composition of this embodiment contains a sensitizing dye as (D) component from a viewpoint of improving a sensitivity and a resist shape. (D) As sensitizing dyes, pyrazolines, anthracenes, coumarins, xanthones, oxazoles, benzoxazoles, thiazoles, benzothiazoles, triazoles, stilbenes, triazines, thiophenes, naphthalimides And tertiary amines. These may be used alone or in combination of two or more.

  (D) It is preferable that the sensitizing dye is one that can effectively utilize the absorption wavelength of the active light to be used. For example, when exposure is performed using a 405 nm blue-violet laser diode as a light source, a compound having a maximum absorption wavelength (wavelength indicating an absorption maximum) of 370 nm to 420 nm is preferably used as a sensitizing dye. From the viewpoint of having a large extinction coefficient and improving the resolution and adhesion with a small content, it is preferable to use pyrazolines.

  By using such a sensitizing dye, it becomes possible to have a sufficiently high sensitivity to the exposure light of the direct drawing exposure method. If the maximum absorption wavelength of the sensitizing dye is less than 370 nm, the sensitivity to direct drawing exposure light tends to be insufficient, and if it is 420 nm or more, the stability tends to be insufficient even in a yellow light environment.

  (D) The content of the sensitizing dye is preferably 0.01 to 10 parts by mass, and 0.05 to 5 parts by mass with respect to 100 parts by mass of the total amount of the components (A) and (B). More preferably, the content is 0.1 to 2 parts by mass. If this amount is less than 0.01 parts by mass, sufficiently good sensitivity and resolution tend not to be obtained, and if it exceeds 10 parts by mass, a sufficiently good resist shape tends not to be obtained.

<(E) component: amine compound>
Furthermore, from the viewpoint of improving sensitivity, the photosensitive resin composition of the present embodiment preferably contains an amine compound as the component (E). Examples of (E) amine compounds include bis [4- (dimethylamino) phenyl] methane, bis [4- (diethylamino) phenyl] methane, and leucocrystal violet. These may be used alone or in combination of two or more.

  (E) The content of the amine compound is preferably 0.01 to 10 parts by mass, and 0.05 to 5 parts by mass with respect to 100 parts by mass of the total amount of the components (A) and (B). More preferably, the content is 0.1 to 2 parts by mass. If the blending amount is less than 0.01 parts by mass, a sufficiently good sensitivity tends not to be obtained, and if it exceeds 10 parts by mass, it tends to precipitate as a foreign substance after pattern formation.

<Other ingredients>
Furthermore, the photosensitive resin composition of the present embodiment includes, as necessary, a photopolymerizable compound (such as an oxetane compound) having at least one cationically polymerizable cyclic ether group in the molecule; a cationic polymerization initiator; and malachite green. Dyes such as tribromophenylsulfone and leucocrystal violet; thermochromic agents; plasticizers such as p-toluenesulfonamide; pigments, fillers, antifoaming agents, flame retardants, stabilizers, adhesion You may contain an imparting agent, a leveling agent, a peeling accelerator, antioxidant, a fragrance | flavor, an imaging agent, a thermal crosslinking agent, etc. These may be used alone or in combination of two or more. These contents are preferably about 0.01 to 20 parts by mass with respect to 100 parts by mass of the total amount of component (A) (binder polymer) and component (B) (photopolymerizable compound).

(Photosensitive resin composition solution)
The photosensitive resin composition of this embodiment can be dissolved in an organic solvent and used as a solution (coating solution) having a solid content of about 30 to 60% by mass. Examples of the organic solvent include methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N-dimethylformamide, propylene glycol monomethyl ether, or a mixed solvent thereof.

  The said coating liquid is apply | coated on surfaces, such as a metal plate, and the photosensitive resin layer formed using the photosensitive resin composition of this embodiment can be formed by making it dry. Examples of the metal plate include iron alloys such as copper, copper alloys, nickel, chromium, iron, and stainless steel, preferably copper, copper alloys, and iron alloys.

  The thickness of the photosensitive resin layer varies depending on the application, but is preferably about 1 to 100 μm in thickness after drying. The surface of the photosensitive resin layer opposite to the metal plate may be covered with a protective film. Examples of the protective film include polymer films such as polyethylene and polypropylene.

(Photosensitive element)
FIG. 1 shows an embodiment of the photosensitive element of the present invention. Forming the photosensitive resin layer 3 formed using the photosensitive resin composition on the support film 2 by applying the solution of the photosensitive resin composition on the support film 2 and drying it. it can. Next, the surface of the photosensitive resin layer 3 opposite to the supporting film 2 is covered with a protective film 4, thereby supporting the supporting film 2, the photosensitive resin layer 3 laminated on the supporting film 2, and the photosensitive film. The photosensitive element 1 of this embodiment provided with the protective film 4 laminated | stacked on the photosensitive resin layer 3 is obtained. The protective film 4 is not necessarily provided.

  As the support film 2, a polymer film having heat resistance and solvent resistance, such as polyethylene terephthalate, polypropylene, polyethylene, and polyester, can be used. The thickness of the support film 2 (polymer film) is preferably 1 to 100 μm, more preferably 5 to 50 μm, and still more preferably 5 to 30 μm. When the thickness is less than 1 μm, the support film 2 tends to be easily broken when the support film 2 is peeled off, and when it exceeds 100 μm, the resolution tends to be difficult to obtain sufficiently.

  The protective film 4 preferably has a lower adhesive force to the photosensitive resin layer 3 than the adhesive force of the support film 2 to the photosensitive resin layer 3 and is preferably a low fisheye film. Here, “fish eye” means that when a material is heat-melted, kneaded, extruded, biaxially stretched, casting method, etc., foreign materials, undissolved materials, oxidatively deteriorated materials, etc. are present in the film. It means what was taken in. That is, “low fish eye” means that the above-mentioned foreign matter or the like in the film is small.

  Specifically, as the protective film 4, a polymer film having heat resistance and solvent resistance such as polyethylene terephthalate, polypropylene, polyethylene, and polyester can be used. Examples of commercially available products include polypropylene films such as Alphan MA-410 and E-200C manufactured by Oji Paper Co., Ltd., Shin-Etsu Film Co., Ltd., and polyethylene terephthalate films such as PS series such as PS-25 manufactured by Teijin Limited. The protective film 4 may be the same as the support film 2.

  The thickness of the protective film 4 is preferably 1 to 100 μm, more preferably 5 to 50 μm, still more preferably 5 to 30 μm, and particularly preferably 15 to 30 μm. When the thickness is less than 1 μm, the protective film 4 tends to be easily broken when the photosensitive resin layer 3 and the protective film 4 are laminated (laminated) on the substrate, and when the thickness exceeds 100 μm, the cost is sufficiently low. Tend to disappear.

  Application of the solution of the photosensitive resin composition onto the support film 2 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.

  The solution is preferably dried at 70 to 150 ° C. for about 5 to 30 minutes. After drying, the amount of the remaining organic solvent in the photosensitive resin layer is preferably 2% by mass or less from the viewpoint of preventing diffusion of the organic solvent in the subsequent step.

  Although the thickness of the photosensitive resin layer 3 in the photosensitive element 1 varies depending on the use, it is preferably 1 to 100 μm, more preferably 1 to 50 μm, and more preferably 5 to 40 μm after drying. Further preferred. When this thickness is less than 1 μm, it tends to be difficult to apply industrially, and when it exceeds 100 μm, adhesion and resolution tend to be difficult to obtain sufficiently.

  The transmittance of the photosensitive resin layer with respect to ultraviolet rays is preferably 5 to 75%, more preferably 10 to 65%, and particularly preferably 15 to 55% with respect to ultraviolet rays having a wavelength of 405 nm. . If this transmittance is less than 5%, sufficient adhesion tends to be difficult to obtain, and if it exceeds 75%, sufficient resolution tends to be difficult to obtain. The transmittance can be measured with a UV spectrometer. An example of the UV spectrometer is a 228A type W beam spectrophotometer manufactured by Hitachi, Ltd.

  The photosensitive element 1 may further include an intermediate layer such as a cushion layer, an adhesive layer, a light absorption layer, and a gas barrier layer.

  The obtained photosensitive element 1 can be stored in the form of a sheet or a roll wound around a core. When winding in roll form, it is preferable to wind up so that the support film 2 may become an outer side. Examples of the winding core include plastics such as polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, and ABS resin (acrylonitrile-butadiene-styrene copolymer). From the viewpoint of end face protection, it is preferable to install an end face separator on the end face of the roll-shaped photosensitive element roll thus obtained, and it is preferable to install a moisture-proof end face separator from the standpoint of edge fusion resistance. As a packaging method, it is preferable to wrap and package in a black sheet with low moisture permeability.

(Method for forming resist pattern)
A resist pattern can be formed using the photosensitive resin composition. The resist pattern forming method according to the present embodiment includes (i) a lamination step of laminating a photosensitive resin layer formed using the photosensitive resin composition on a substrate, and (ii) a predetermined photosensitive resin layer. An exposure step of irradiating a portion with an actinic ray to expose and cure the predetermined portion; and (iii) removing a portion other than the predetermined portion of the photosensitive resin layer from the substrate, thereby exposing the photosensitive portion on the substrate. And a development step of forming a resist pattern made of a cured product of the resin composition.

(I) Lamination process First, the photosensitive resin layer formed using the photosensitive resin composition is laminated | stacked on a board | substrate. As the substrate, a substrate (circuit forming substrate) including an insulating layer and a conductor layer formed on the insulating layer can be used.

  Lamination of the photosensitive resin layer on the substrate is performed, for example, by removing the protective film 4 of the photosensitive element 1 and then pressing the photosensitive resin layer 3 of the photosensitive element 1 on the substrate while heating. Is called. Thereby, the laminated body which consists of a board | substrate, the photosensitive resin layer 3, and the support film 2, and these were laminated | stacked in order is obtained.

  This lamination operation is preferably performed under reduced pressure from the viewpoint of adhesion and followability. The photosensitive resin layer and / or the substrate is preferably heated at a temperature of 70 to 130 ° C. during the pressure bonding, and is pressure bonded at a pressure of about 0.1 to 1.0 MPa (about 1 to 10 kgf / cm 2). However, these conditions are not particularly limited. In addition, if the photosensitive resin layer is heated to 70 to 130 ° C., it is not necessary to pre-heat the substrate in advance, but the substrate can be pre-heated in order to further improve the stackability.

(Ii) Exposure Step Next, a predetermined portion of the photosensitive resin layer on the substrate is irradiated with actinic rays to expose and cure the predetermined portion. At this time, when the support film 2 existing on the photosensitive resin layer 3 is transparent to actinic rays, it can be irradiated with actinic rays through the support film 2, but the support film 2 is light-shielding. In some cases, the photosensitive resin layer is irradiated with actinic rays after the support film 2 is removed.

  Examples of the exposure method include a method (mask exposure method) of irradiating an image with active light through a negative or positive mask pattern called an artwork. Alternatively, a method of irradiating active rays in an image form by a direct drawing method such as a laser direct drawing exposure method or a DLP (Digital Light Processing) exposure method may be employed.

  As the actinic ray light source, a known light source can be used. For example, a carbon arc lamp, a mercury vapor arc lamp, a high pressure mercury lamp, a xenon lamp, a gas laser such as an argon laser, a solid laser such as a YAG laser, a semiconductor laser, etc. Those that effectively emit ultraviolet light, visible light, and the like are used.

  The wavelength of the actinic ray (exposure wavelength) is preferably in the range of 350 to 420 nm, more preferably in the range of 390 to 420 nm, from the viewpoint of obtaining the effects of the present invention more reliably.

(Iii) Development Step Further, a resist pattern made of a cured product of the photosensitive resin composition is formed on the substrate by removing portions other than the predetermined portion of the photosensitive resin layer from the substrate. When the support film is present on the photosensitive resin layer, after removing the support film, removal (development) of portions (unexposed portions) other than the predetermined portion (exposed portion) is performed. Development methods include wet development and dry development, but wet development is widely used.

  In the case of wet development, development is performed by a known development method using a developer corresponding to the photosensitive resin composition. Examples of the developing method include a method using a dip method, a battle method, a spray method, brushing, slapping, scraping, rocking immersion, and the like. From the viewpoint of improving the resolution, the high pressure spray method is most suitable. You may develop by combining these 2 or more types of methods.

  Examples of the developer include an alkaline aqueous solution, an aqueous developer, an organic solvent developer, and the like.

  The alkaline aqueous solution is safe and stable when used as a developer, and has good operability. Examples of the base of the alkaline aqueous solution include alkali hydroxides such as lithium, sodium, or potassium hydroxide; alkali carbonates such as lithium, sodium, potassium, or ammonium carbonate or bicarbonate; potassium phosphate, sodium phosphate, and the like. Alkali metal phosphates; alkali metal pyrophosphates such as sodium pyrophosphate and potassium pyrophosphate are used.

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

  The aqueous developer is, for example, a developer composed of water or an alkaline aqueous solution and one or more organic solvents. Here, as the base of the alkaline aqueous solution, in addition to the substances described above, for example, borax, sodium metasilicate, tetramethylammonium hydroxide, ethanolamine, ethylenediamine, diethylenetriamine, 2-amino-2-hydroxymethyl-1 , 3-propanediol, 1,3-diaminopropanol-2, morpholine and the like. The pH of the aqueous developer is preferably as low as possible within a range where development is sufficiently performed, preferably pH 8 to 12, and more preferably pH 9 to 10.

  Examples of the organic solvent used in the aqueous developer include acetone, ethyl acetate, alkoxyethanol having an alkoxy group having 1 to 4 carbon atoms, ethyl alcohol, isopropyl alcohol, butyl alcohol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether. Etc. These are used alone or in combination of two or more. In general, the concentration of the organic solvent in the aqueous developer is preferably 2 to 90% by mass, and the temperature can be adjusted according to alkali developability. A small amount of a surfactant, an antifoaming agent or the like can be mixed in the aqueous developer.

  Examples of the organic solvent developer include organic solvents such as 1,1,1-trichloroethane, N-methylpyrrolidone, N, N-dimethylformamide, cyclohexanone, methyl isobutyl ketone, and γ-butyrolactone. It is preferable to add water to these organic solvents in the range of 1 to 20% by mass in order to prevent ignition.

  After removing the unexposed portion, the resist pattern may be further cured by heating at about 60 to 250 ° C. or exposure at about 0.2 to 10 J / cm 2 as necessary.

(Printed wiring board manufacturing method)
A printed wiring board can be manufactured by etching or plating a substrate on which a resist pattern is formed by the above method. Etching or plating of the substrate is performed on the conductor layer of the substrate using the formed resist pattern as a mask.

  Etching solutions used for etching include cupric chloride solution, ferric chloride solution, alkaline etching solution, and hydrogen peroxide etching solution. It is preferable to use an iron solution.

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

  After the etching or plating is completed, the resist pattern can be peeled off with a stronger alkaline aqueous solution than the alkaline aqueous solution used for development, for example. As this strongly alkaline aqueous solution, for example, a 1 to 10% by mass sodium hydroxide aqueous solution, a 1 to 10% by mass potassium hydroxide aqueous solution and the like are used. Especially, it is preferable to use 1-10 mass% sodium hydroxide aqueous solution or potassium hydroxide aqueous solution, and it is more preferable to use 1-5 mass% sodium hydroxide aqueous solution or potassium hydroxide aqueous solution.

  Examples of the resist pattern peeling method include an immersion method and a spray method, which 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 more specifically with reference to examples. However, the present invention is not limited to the following examples.

[Binder polymer (A-1)]
Preparation of Solution a 9.0 g of azobisisobutyronitrile, which is a radical reaction initiator, was dissolved in a mixed solution composed of polymerizable monomers (copolymerization monomers, monomers) shown in Table 1 to obtain “solution a "was prepared.

Preparation of Solution b 1.2 g of azobisisobutyronitrile as a radical reaction initiator was dissolved in 100 g of a mixed solution (mass ratio 3: 2) of 60 g of propylene glycol monomethyl ether as an organic solvent and 40 g of toluene. Solution b "was prepared.

Radical polymerization reaction In a flask equipped with a stirrer, reflux condenser, thermometer, dropping funnel and nitrogen gas introduction tube, 450 g of a mixed solution of propylene glycol monomethyl ether (180 g) and 180 g of toluene (mass ratio 3: 2) was added. I put it in. While the nitrogen gas was blown into the flask, the mixture was heated while stirring to raise the temperature to 80 ° C.

  The solution a was dropped into the mixed solution in the flask over 4 hours, and the solution in the flask was kept at 80 ° C. for 2 hours while stirring. Next, the solution b was added dropwise to the solution in the flask over 10 minutes, and then the solution in the flask was kept at 80 ° C. for 3 hours while stirring. Furthermore, the solution in the flask was heated to 90 ° C. over 30 minutes, kept at 90 ° C. for 2 hours, and then cooled to obtain a binder polymer (A-1) solution.

The binder polymer (A-1) had a non-volatile content (solid content) of 47.8% by mass, a weight average molecular weight of 30000, and an acid value of 196 mgKOH / g. The weight average molecular weight was measured by gel permeation chromatography (GPC) and derived by conversion using a standard polystyrene calibration curve. The conditions for GPC are as follows.
GPC condition pump: Hitachi L-6000 type (manufactured by Hitachi, Ltd.)
Column: Total of 3
Gelpack GL-R420
Gelpack GL-R430
Gelpack GL-R440 (above, manufactured by Hitachi Chemical Co., Ltd., trade name)
Eluent: Tetrahydrofuran Measurement temperature: 40 ° C
Flow rate: 2.05 mL / min Detector: Hitachi L-3300 type RI (manufactured by Hitachi, Ltd.)

[Binder polymer (A-2)]
A solution prepared by dissolving 9.0 g of azobisisobutyronitrile as a radical reaction initiator in a mixed solution composed of polymerizable monomers shown in Table 2 was prepared, and this solution was used in place of the solution a. Obtained a solution of the binder polymer (A-2) in the same manner as the solution of the binder polymer (A-1). The binder polymer (A-2) had a non-volatile content (solid content) of 40.0% by mass, a weight average molecular weight of 30000, and an acid value of 196 mgKOH / g.

[Photopolymerizable compound (B-1)]
In a three-necked flask equipped with a nitrogen gas inlet tube, 50 g (0.036 mol) of bisphenol A type phenol novolac type epoxy compound manufactured by Japan Chemtech Co., Ltd., 31.0 g (0.36 mol) of methacrylic acid, p-toluenesulfone 0.5 g of acid pyridinium salt and 100 g of THF as a solvent were added, and these were stirred at room temperature overnight to be reacted. After neutralizing the reaction solution with sodium carbonate, the organic solvent-soluble matter in the reaction solution was extracted with ethyl acetate. After the solvent in the extract was distilled off with an evaporator, recrystallization was performed using an ethyl acetate / hexane mixed solvent to obtain a photopolymerizable compound (B-1) represented by the following formula (B-1). .

[Solution of photosensitive resin composition]
By mixing the components shown in Table 3 below at a mass ratio shown in Table 3, solutions of the photosensitive resin compositions of Examples 1 to 5 and Comparative Example 1 were prepared. In addition, the mass ratio of (A) component (binder polymer) shown in Table 3 is a mass ratio with respect to a non-volatile content (solid content).

Details of each component shown in Table 3 are as follows.
(B) component: photopolymerizable compound (B ″) component: photopolymerizable unsaturated compound having two or more polymerizable ethylenically unsaturated bonds in the molecule, BPE-100 (Shin Nakamura Chemical Co., Ltd.) ) Product name:
2,2-bis (4- (methacryloxyethoxy) phenyl) propane (EO 2.6 mol): bisphenol A-based (meth) acrylate compound FA-321M (trade name, manufactured by Hitachi Chemical Co., Ltd.):
2,2-bis (4- (methacryloxypentaethoxy) phenyl) propane:
Bisphenol A-based (meth) acrylate compound / TMPT21 (trade name, manufactured by Hitachi Chemical Co., Ltd.):
EO-modified trimethylolpropane trimethacrylate (21 mol adduct with an average of ethylene oxide): Compound obtained by reacting polyhydric alcohol with α, β-unsaturated carboxylic acid. FA-024M (manufactured by Hitachi Chemical Co., Ltd., product) Name):
In the general formula (6b), R6 = methyl group, m3 = 6 (average value), n2 + n3 = 12 (average value): Polyalkylene glycol di (meth) acrylate (B ′) component: Photopolymerizable unsaturated compound having two polymerizable ethylenically unsaturated bonds, FA-MECH (trade name, manufactured by Hitachi Chemical Co., Ltd.):
γ-chloro-β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate: phthalic acid compound

Component (C): Photopolymerization initiator / BCIM (product name, manufactured by Hampford):
2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenylbisimidazole: hexaarylbiimidazole derivative

Component (D): Sensitizing dye, Nikka Flow MC (trade name, manufactured by Nippon Chemical Industry Co., Ltd.):
1-phenyl-3- (4-t-butylstyryl) -5- (4-t-butylphenyl) pyrazoline Wavelength [λn] = 387.2 nm showing the absorption maximum
DBA (manufactured by Kawasaki Kasei Kogyo Co., Ltd., trade name): 9,10-dibutoxyanthracene [λn] = 368 nm, 388 nm, 410 nm indicating the absorption maximum
(D-1): 1-phenyl-3- (4-isopropylstyryl) -5- (4-isopropylphenyl) pyrazoline wavelength [λn] = 386.2 nm showing absorption maximum
-(D-2): J205 (made by Nippon Distillation Industry Co., Ltd., trade name)
Triphenylamine derivative represented by the following formula (5) Wavelength [λn] = 410 nm showing absorption maximum

Component (E): amine compound (hydrogen donor)
LCV: Leuco Crystal Violet (Yamada Chemical Co., Ltd., trade name)

Dye: Malachite Green (trade name, manufactured by Osaka Organic Chemical Industry Co., Ltd.)

[Photosensitive element]
The solutions of the photosensitive resin compositions of Examples 1 to 5 and Comparative Example 1 were uniformly applied onto a polyethylene terephthalate film (product name “HTF-01” manufactured by Teijin Limited) with a thickness of 16 μm, It dried with the hot air convection type dryer of 70 degreeC and 110 degreeC, and formed the photosensitive resin layer whose film thickness after drying is 40 micrometers. A protective film (manufactured by Tamapoly Co., Ltd., product name “NF-15”) was laminated on the photosensitive resin layer by roll pressurization to form a polyethylene terephthalate film (supporting film) and the film thereon. The photosensitive element of Examples 1-5 and Comparative Example 1 which consist of each photosensitive resin layer and the protective film formed on it was obtained.

[Laminated substrate]
The copper surface of a copper-clad laminate (made by Hitachi Chemical Co., Ltd., product name MCL-E-67) consisting of a glass epoxy material and copper foil (thickness 35 μm) formed on both sides is equivalent to # 600 Polishing was performed using a polishing machine having a brush (manufactured by Sankei Co., Ltd.), washed with water, and dried with an air stream. After heating this copper clad laminate (hereinafter referred to as “substrate”) to 80 ° C., the photosensitive elements of Examples 1 to 5 and Comparative Example 1 were laminated on the copper surfaces on both sides of the substrate. (Laminated). Lamination was performed under conditions of a temperature of 120 ° C. and a pressure of 4 kgf / cm 2 so that the photosensitive resin layer of each photosensitive element was in close contact with each copper surface of the substrate while removing the protective film. Thus, the laminated substrate by which the photosensitive resin layer and the polyethylene terephthalate film were laminated | stacked on the copper surface of the both sides of a board | substrate was obtained.

(Evaluation of sensitivity)
The obtained multilayer substrate was allowed to cool and when the temperature reached 23 ° C., a phototool having a step tablet was brought into close contact with the polyethylene terephthalate film on the surface of the multilayer substrate. As the step tablet, a 41-step step tablet having a density region of 0.00 to 2.00, a density step of 0.05, a tablet size of 20 mm × 187 mm, and each step size of 3 mm × 12 mm was used. . The photosensitive resin layer was exposed (drawn) through a phototool having such a step tablet and a polyethylene terephthalate film. The exposure was performed using “EXM1201” (trade name) manufactured by Oak Manufacturing Co., Ltd.

  After the exposure, the polyethylene terephthalate film was peeled off from the laminated substrate to expose the photosensitive resin layer. The exposed photosensitive resin layer was sprayed (development treatment) with a 1% by mass aqueous sodium carbonate solution at 30 ° C. for 60 seconds to remove unexposed portions. Thus, the cured film which consists of hardened | cured material of the photosensitive resin composition was formed in the copper surface of a laminated substrate. The number of steps of the step tablet of the obtained cured film was measured, and the amount of exposure (mJ / cm 2) when the number of remaining step steps was 12 was determined, whereby the photosensitive resin compositions of Examples 1 to 5 and Comparative Example 1 were obtained. The sensitivity (photosensitivity) of the object and the photosensitive element was evaluated. The smaller the exposure value, the better the sensitivity. The results are shown in Table 4.

(Evaluation of resolution and adhesion)
Using the drawing pattern whose line width (L) / space width (S) is 5/5 to 30/30 (unit: μm), the photosensitive resin layer of the laminated substrate was exposed (drawn). . The exposure was performed with an energy amount such that the number of stages after development of the 41-step tablet was 12. After the exposure, the same development processing as in the sensitivity evaluation was performed.

  The minimum resolution of the line width or space width of the drawing pattern used when the space part (unexposed part) is removed cleanly and the line part (exposed part) is formed without meandering or chipping. Sex was evaluated. The smaller this minimum value, the better the resolution and adhesion. The results are shown in Table 4.

(Evaluation of resist shape)
In the evaluation of the resolution and adhesion, the obtained resist shape (cross-sectional shape of the resist pattern) was observed using a Hitachi scanning electron microscope S-500A. The results are shown in Table 4. When the resist shape is trapezoidal or inverted trapezoidal, or when there is a tailing of the resist, there is a tendency that a short circuit or disconnection tends to occur in a circuit formed by the subsequent etching process or plating process. Therefore, it is desirable that the resist shape is rectangular (rectangular) and the resist is not skirted.

(Evaluation of peeling properties)
Each photosensitive element was laminated on the copper-clad laminate (substrate) and exposed and developed under the following conditions to produce a test piece (40 mm × 50 mm) having a cured film formed on the substrate. .
<Exposure conditions>
Exposure machine: “EXM1201” (trade name) manufactured by Oak Manufacturing Co., Ltd.
Exposure amount: 60-70mJ / cm2
Size: 40mm x 50mm
<Development conditions>
Developer: 1% by weight Na2CO3
Liquid temperature: 30 ° C
Spray type

  The test piece was allowed to stand at room temperature for a whole day and night, then immersed (dip) in a 3 mass% sodium hydroxide aqueous solution (stripping solution) at 50 ° C., and stirred with a stirrer. The peeling characteristics were evaluated by the time from the start of stirring until the cured film was completely peeled off from the substrate (peeling time) and the size of the peeled pieces. It means that the shorter the peeling time is, and the smaller the peeling piece size is, the better the peeling properties are. In addition, the peeling piece size is L for sheet-like ones, M for 30 to 40 mm square, and S for 30 mm square or less. The results are shown in Table 4.

  As is clear from the results shown in Table 4, the photosensitive resin compositions of Examples 1 to 5 are more sensitive than the photosensitive resin composition of Comparative Example 1 that does not contain (B-1) as the component (B). , Resolution and adhesion, resist shape, and release properties after curing were all good.

  The photosensitive resin composition of this invention is applied as a material which forms the resist pattern of a printed wiring board. In particular, since the photosensitive resin composition has good sensitivity, resolution, adhesion, resist shape, and release characteristics after curing, the printed wiring board having high-density wiring such as a high-density package substrate. It is also suitably used for resist pattern formation.

  DESCRIPTION OF SYMBOLS 1 ... Photosensitive element, 2 ... Support film, 3 ... Photosensitive resin layer, 4 ... Protective film.

Claims (7)

(A) a binder polymer, (B) a photopolymerizable compound , (C) a photopolymerization initiator, and (D) a photosensitive resin composition containing a sensitizing dye , wherein (B) the photopolymerizable compound is: look containing a compound represented by the general formula (1),
The photosensitive resin composition in which the compound represented by the said General formula (1) contains the compound represented by the following general formula (2) .

[In the general formula (1), each R ¹ independently represents a hydrogen atom or a methyl group, each X independently represents a divalent organic group, each Y independently represents a monovalent organic group, m Represents an integer of 0 to 4, and n represents an integer of 0 to 10. ]

[In the general formula (2), each R ¹ independently represents a hydrogen atom or a methyl group, each X independently represents a divalent organic group, and each R ² independently represents a hydrogen atom, a phenyl group, or carbon. An alkyl group or cycloalkyl group having 1 to 10 atoms is shown, and n is an integer of 0 to 10. ] The photosensitive resin composition of Claim 1 in which the said (C) photoinitiator contains a hexaaryl biimidazole derivative. (E) The photosensitive resin composition of Claim 1 or 2 containing an amine compound. A photosensitive element comprising: a support film; and a photosensitive resin layer formed using the photosensitive resin composition according to any one of claims 1 to 3 formed on the support film. A laminating step of laminating a photosensitive resin layer formed using the photosensitive resin composition according to any one of claims 1 to 3 on a substrate;
An exposure step of irradiating the predetermined portion of the photosensitive resin layer with an actinic ray to expose and cure the predetermined portion;
A developing step of forming a resist pattern made of a cured product of the photosensitive resin composition on the substrate by removing portions other than the predetermined portion of the photosensitive resin layer from the substrate. Pattern formation method. The resist pattern forming method according to claim 5 , wherein, in the exposure step, the predetermined portion is exposed and cured by directly irradiating the photosensitive resin layer with a laser beam having a predetermined pattern. The manufacturing method of a printed wiring board including etching or plating the board | substrate with which the resist pattern was formed by the method of Claim 5 or 6 .