JPWO2006009076A1 - Photosensitive element, resist pattern forming method using the same, and printed wiring board manufacturing method - Google Patents

Abstract

The photosensitive element of the present invention includes a support film 10, a cushion layer 12 formed on the support film 10, and a photosensitive layer 14 formed on the cushion layer 12 and having a thickness of 10 μm or less. The photosensitive layer 14 includes a binder polymer having a weight average molecular weight of 10,000 to 100,000, a first photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond in the molecule, The cushion layer 12 includes a second photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond in the molecule, and a second photopolymerization. It is a layer comprising an initiator.

Description

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

  Conventionally, a photosensitive element in which a photosensitive layer is laminated on a support film has been widely used as a resist material used for etching, plating and the like in the field of manufacturing printed wiring boards and the field of precision metal processing. The photosensitive element generally has a form in which a protective film is laminated after forming a photosensitive layer on a support film.

  As a method of using the photosensitive element, the following methods are common. First, after the protective film is peeled off, the photosensitive layer is pressure-bonded (laminated) so as to directly touch the base material (copper substrate or the like). Next, a patterned photo tool is brought into close contact with the light transmissive film, and actinic rays such as ultraviolet rays are irradiated (exposed). Thereafter, a resist pattern is formed (developed) by spraying a developer to remove the unexposed portions.

  As the developer used for removing the unexposed portion, it can be used as long as it has an ability to dissolve or disperse the photosensitive layer to some extent. Currently, there is an alkali developing type using an aqueous sodium carbonate solution or an aqueous sodium hydrogen carbonate solution. It has become mainstream. At the time of development, the photosensitive resin composition forming the photosensitive layer is dissolved or dispersed in the developer.

  In many cases, irregularities due to dents or the like exist on the substrate of the printed wiring board. Therefore, the transition layer (photosensitive layer, support film, etc.) to be affixed to the substrate has sufficient followability to the unevenness of the substrate so that an unbonded portion does not occur between the photosensitive layer and the substrate when laminating. It is hoped that If there is an unbonded portion between the photosensitive layer and the substrate, an unbonded portion will be formed between the resist film and the substrate after exposure. For example, when etching is performed thereafter, the conductor may be broken or disconnected. The defect occurs.

  In recent years, the density of printed wiring boards has been increased, and high resolution is required. In order to increase the resolution of the photosensitive element for circuit formation, it is effective to reduce the thickness of the photosensitive layer. However, since the amount of the photosensitive layer that follows the unevenness on the surface of the substrate decreases, in the conventional photosensitive element, There is a problem that an unbonded portion between the substrate and the photosensitive layer increases, and a sufficient production yield cannot be obtained. Also, in the conventional photosensitive element, the flexibility and the entire transition layer becomes insufficient due to the thickness and hardness required of the support film, and it is difficult for the transition layer to follow the unevenness of the substrate surface. There is a problem that an unbonded portion between the layers increases and a sufficient production yield cannot be obtained.

  In order to improve such a problem, various methods have been proposed. For example, after applying water to a substrate, a method of laminating a photosensitive element (see, for example, Patent Documents 1 and 2), after laminating a liquid resin on a substrate to form an adhesive intermediate layer, the photosensitive element Have been proposed (for example, see Patent Document 3), a method of laminating photosensitive elements under reduced pressure using a vacuum laminator (for example, see Patent Documents 4 and 5), and the like.

  In addition, as a photosensitive element having followability with respect to the unevenness of the substrate surface, a photosensitive element having a thermoplastic resin layer, an intermediate layer, and a photosensitive layer on a support film has been proposed (see, for example, Patent Document 6). .

Furthermore, a photosensitive element having a cushion layer and a photosensitive layer on a support film has been disclosed as a photosensitive element that has followability with respect to irregularities on the substrate surface and can obtain high resolution (see, for example, Patent Document 7). ).
JP 57-21890 A JP-A-57-21891 JP-A-52-154363 Japanese Patent Publication No.53-31670 Japanese Patent Laid-Open No. 51-63702 JP-A-5-80503 JP 2003-5364 A

  However, in the methods described in Patent Documents 1 and 2, in order to uniformly deposit a thin layer of water, the surface of the substrate must be cleaned, and when a small-diameter through-hole is present, There is a problem in that the accumulated moisture and the photosensitive layer are liable to react and the developability is lowered.

  In the method described in Patent Document 3, there are problems in that the developability and releasability of the small-diameter through hole are lowered, and there are problems such as an increase in cost due to liquid resin application.

  In the methods described in Patent Documents 4 and 5, since the apparatus is expensive and it takes time to evacuate, it is rarely used for forming a normal circuit and is used as a laminate for a permanent mask used after forming a conductor. It ’s just that. Even when the permanent mask is laminated, further improvement in the followability to the conductor is desired.

  In the photosensitive element described in Patent Document 6, the followability to the unevenness of the substrate surface is improved. However, after laminating the transition layer on the substrate, the support film is peeled off and exposed to the thermoplastic resin layer and the intermediate layer. Since the layer exists between the photosensitive layer and the negative mask, there is a problem that high resolution is difficult to obtain.

  In the photosensitive element described in Patent Document 7, the problem that the photopolymerizable compound, photoinitiator, additive, and the like contained in the photosensitive resin composition layer easily transfer to the cushion layer depending on the use environment or storage environment of the film. was there. Usually, the photosensitive element is used and stored at room temperature. However, even in such an environment, the above problem occurs, and sufficient aging stability cannot be obtained. And when a part of material contained in a photosensitive layer transfers to a cushion layer, the suitable material ratio of a photosensitive layer changes. That is, since the characteristics of the photosensitive element change, there arises a problem that the manufacturing yield of circuit formation is lowered.

  The present invention has been made in view of the above-mentioned problems of the prior art, and has sufficient followability to the unevenness of the substrate surface to be laminated, and has excellent adhesion, resolution, and aging stability. The purpose is to provide sex elements. Another object of the present invention is to provide a method for forming a resist pattern using the photosensitive element and a method for producing a printed wiring board.

  In order to achieve the above object, the present invention includes a support film, a cushion layer formed on the support film, and a photosensitive layer having a thickness of 10 μm or less formed on the cushion layer. The layer comprises a binder polymer having a weight average molecular weight of 10,000 to 100,000, a first photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond in the molecule, and a first photopolymerization. An initiator, and the cushion layer includes a second photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond in the molecule and a second photopolymerizable compound. Provided is a photosensitive element, which is a layer containing a photopolymerization initiator.

  According to such a photosensitive element, by having the cushion layer, even when the photosensitive resin composition layer is thinned for high resolution, the photosensitive layer is formed during lamination due to the presence of the cushion layer. Can be adhered with good followability along the unevenness of the substrate surface, and generation of an unbonded portion between the substrate and the photosensitive layer can be sufficiently suppressed. Furthermore, since the cushion layer contains a photopolymerizable compound and a photopolymerization initiator, the photopolymerizable compound and the photopolymerization initiator contained in the photosensitive layer are sufficiently suppressed from moving to the cushion layer. Can be obtained, and sufficient aging stability can be obtained. Further, when the binder polymer contained in the photosensitive layer has a weight average molecular weight of 10,000 to 100,000, it is possible to reduce the residual thread-like development occurring at a portion where the space between the resist patterns is narrow, and to improve the resolution. Thereby, the side surface of the resist pattern can be made favorable. Therefore, according to the photosensitive element of the present invention, it is possible to achieve all of the uneven followability, adhesion, resolution, and aging stability at a high level, and a sufficient manufacturing yield can be obtained. In addition, since it has excellent unevenness followability, the photosensitive layer can be laminated on the substrate without increasing production costs and without causing transfer defects due to minute dust, bubbles, unevenness of the substrate surface, etc. .

  In the photosensitive element of the present invention, the support film preferably has a thickness of 5 to 20 μm. When the thickness of the support film is in the above range, more sufficient unevenness followability can be obtained.

  In the photosensitive element of the present invention, the binder polymer preferably contains styrene and / or a styrene derivative as a monomer unit. As a result, sufficient adhesion can be obtained, and excellent chemical resistance (plating resistance) can be obtained, which is useful for increasing the density and resolution of printed wiring.

  In the photosensitive element of the present invention, the binder polymer preferably contains methacrylic acid as a monomer unit. As a result, the effects of the present invention can be sufficiently obtained, and excellent alkali developer properties can be obtained, which is useful for increasing the density and resolution of printed wiring.

  In the photosensitive element of the present invention, the acid value of the binder polymer is preferably 30 to 200 mgKOH / g. As a result, the effects of the present invention can be sufficiently obtained, and excellent alkali developer properties can be obtained, which is useful for increasing the density and resolution of printed wiring.

  The photosensitive element of the present invention preferably contains a compound having 4 to 40 oxyalkylene groups having 2 to 6 carbon atoms in the molecule as the first photopolymerizable compound and the second photopolymerizable compound. . Thereby, the effects of the present invention can be sufficiently obtained, and excellent photosensitivity, chemical resistance and peelability can be obtained, which is useful for increasing the density and resolution of printed wiring.

  The photosensitive element of the present invention preferably contains a bisphenol A (meth) acrylate compound or a polyalkylene glycol di (meth) acrylate as the first photopolymerizable compound and the second photopolymerizable compound. Thereby, the effects of the present invention can be sufficiently obtained, and excellent photosensitivity, chemical resistance and peelability can be obtained, which is useful for increasing the density and resolution of printed wiring.

［式中、Ｒ^１及びＲ^２はそれぞれ独立に水素原子又はメチル基を示し、Ｘ^１及びＹ^１はそれぞれ独立に炭素数２〜６のアルキレン基を示し、ｐ及びｑはｐ＋ｑ＝４〜４０となるように選ばれる正の整数を示す。］Here, from the viewpoint of obtaining more excellent photosensitivity, chemical resistance, and peelability, the bisphenol A (meth) acrylate compound is preferably a compound represented by the following general formula (1).

[Wherein, R ¹ and R ² each independently represent a hydrogen atom or a methyl group, X ¹ and Y ¹ each independently represent an alkylene group having 2 to 6 carbon atoms, and p and q are p + q = 4 to 40 Indicates a positive integer chosen to be ]

［式中、Ｒ^３及びＲ^４はそれぞれ独立に水素原子又は炭素数１〜３のアルキル基を示し、Ｘ^２、Ｘ^３及びＹ^２はそれぞれ独立に炭素数２〜６のアルキレン基を示し、ｓ、ｔ及びｕはｓ＋ｔ＋ｕ＝４〜４０となるように選ばれる０〜３０の整数を示す。］Moreover, it is preferable that the said polyalkylene glycol di (meth) acrylate is a compound represented by following General formula (2) from a viewpoint of obtaining the more outstanding photosensitivity, chemical-resistance, and peelability.

[Wherein, R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, X ² , X ³ and Y ² each independently represent an alkylene group having 2 to 6 carbon atoms, s, t and u represent integers of 0 to 30 selected so that s + t + u = 4 to 40. ]

  The photosensitive element of the present invention preferably contains a 2,4,5-triarylimidazole dimer as the first photopolymerization initiator and the second photopolymerization initiator. Thereby, more sufficient resolution and adhesion can be obtained, which is useful for increasing the density and resolution of printed wiring.

  In the photosensitive layer in the photosensitive element of the present invention, the blending amount of the first photopolymerizable compound is 30 to 60 parts by mass with the total amount of the binder polymer and the first photopolymerizable compound being 100 parts by mass. In addition, the blending amount of the first photopolymerization initiator is preferably 0.1 to 20 parts by mass with respect to 100 parts by mass of the total amount of the binder polymer and the first photopolymerizable compound. As a result, sufficient resolution and adhesion can be obtained, and excellent photosensitivity, chemical resistance (plating resistance), mechanical strength and flexibility can be obtained. Densification and high resolution of printed wiring It is useful for conversion.

  In the photosensitive element of the present invention, the cushion layer preferably further contains a copolymer of ethylene and a monomer copolymerizable therewith. Thereby, more sufficient uneven | corrugated followable | trackability can be acquired and it is useful for the yield improvement of a printed wiring board.

  Here, from the viewpoint of obtaining more sufficient unevenness followability, the copolymer is an ethylene-vinyl acetate copolymer in which the proportion of the ethylene based on the total amount of monomers constituting the copolymer is 60 to 90% by mass. An ethylene-ethyl (meth) acrylate copolymer in which the proportion of the ethylene based on the total amount of monomers constituting the polymer or the copolymer is 60 to 90% by mass is preferable.

  In the photosensitive element of the present invention, the cushion layer preferably has a thickness of 1 to 100 μm. Thereby, more sufficient uneven | corrugated followable | trackability can be acquired and it is useful for the yield improvement of a printed wiring board.

  The photosensitive element of the present invention preferably further comprises a protective film for covering the photosensitive layer on the photosensitive layer. As a result, the effects of the present invention are sufficiently obtained, and handling and storage are facilitated.

  The present invention also includes a laminating step in which the above-described photosensitive element of the present invention is disposed such that the photosensitive layer, the cushion layer, and the support film are laminated in this order on a circuit forming substrate, and the support film and A peeling step for peeling the cushion layer from the photosensitive layer, an exposure step of irradiating a predetermined portion of the photosensitive layer with actinic rays to form a photocured portion on the photosensitive layer, and the above other than the photocured portion And a developing process for removing the photosensitive layer. A method for forming a resist pattern is provided.

  According to such a resist pattern forming method, since the photosensitive element of the present invention is used, all of the unevenness followability, adhesion, resolution and aging stability are achieved at a high level, and the printed wiring has a high density. It is possible to form a resist pattern useful for increasing the resolution and increasing the resolution.

  The present invention further provides a method for producing a printed wiring board, wherein the circuit forming substrate on which the resist pattern is formed by the resist pattern forming method is etched or plated.

  According to such a method for manufacturing a printed wiring board, since the resist pattern is formed by the method for forming a resist pattern of the present invention, a printed wiring board that achieves high density and high resolution at a high level is manufactured. can do.

  According to the present invention, a photosensitive element having sufficient followability to the unevenness of the substrate surface to be laminated and having excellent adhesion, resolution and aging stability, a method for forming a resist pattern using the photosensitive element, and A method for manufacturing a printed wiring board can be provided.

It is a schematic cross section which shows suitable one Embodiment of the photosensitive element of this invention. (A)-(e) is a series of process figures which show suitable one Embodiment of the formation method of the resist pattern of this invention. It is a schematic cross section which shows other suitable one Embodiment of the photosensitive element of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1, 2 ... Photosensitive element, 10 ... Support film, 12 ... Cushion layer, 14 ... Photosensitive layer, 16 ... Protective film, 18 ... Circuit formation board | substrate, 22 ... Pattern mask.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted. In the present invention, (meth) acrylic acid means acrylic acid and methacrylic acid corresponding to it, and (meth) acrylate means acrylate and methacrylate corresponding thereto.

  FIG. 1 is a schematic sectional view showing a preferred embodiment of the photosensitive element of the present invention. A circuit-forming photosensitive element (hereinafter simply referred to as a photosensitive element) 1 shown in FIG. 1 has a structure in which a cushion layer 12 and a photosensitive layer 14 are sequentially laminated on a support film 10 as a support. The photosensitive layer 14 has a thickness of 10 μm or less, a binder polymer having a weight average molecular weight of 10,000 to 100,000, and a first light having at least one polymerizable ethylenically unsaturated bond in the molecule. A polymerizable compound and a first photopolymerization initiator are included. The cushion layer 12 includes a second photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond in the molecule and a second photopolymerization initiator.

  Hereinafter, each layer which comprises the photosensitive element 1 of this invention is demonstrated.

  The support film 10 is not particularly limited as long as it can support the cushion layer 12 and the photosensitive layer 14. For example, a polymer film having heat resistance and solvent resistance such as polyethylene terephthalate, polypropylene, polyethylene, and polyester is preferably used. Used. The support film 10 may have a single layer structure or may have a multilayer structure in which films having a plurality of compositions are laminated. Further, one side may be subjected to treatment such as embossing and corona treatment.

  Although the thickness in particular of the support film 10 is not restrict | limited, Preferably it is 2-100 micrometers, More preferably, it is 5-20 micrometers, More preferably, it is 8-16 micrometers. If the thickness is less than 2 μm, the support film 10 tends to be broken when the support film 10 and the cushion layer 12 are peeled and removed from the photosensitive element 1. If the thickness exceeds 100 μm, the flexibility of the photosensitive element 1 as a whole decreases. There is a tendency that the followability to the unevenness of the surface of the object to be laminated is lowered.

  The photosensitive layer 14 includes a binder polymer (hereinafter, sometimes referred to as “component (A)”) and a first photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond (hereinafter, “(B1 ) Component) and a first photopolymerizable initiator (hereinafter, sometimes referred to as “component (C1)”).

  The binder polymer as the component (A) needs to have a weight average molecular weight of 10,000 to 100,000. Here, the upper limit value of the weight average molecular weight of the (A) binder polymer is preferably 80,000, more preferably 60,000, still more preferably 30,000, and 25,000. It is particularly preferred. On the other hand, the lower limit of the weight average molecular weight of the (A) binder polymer is preferably 15,000, and more preferably 20,000. When the weight average molecular weight is less than 10,000, the photosensitive layer becomes brittle, and when it exceeds 100,000, a filamentous development residue (insufficient resolution) occurs. In addition, the weight average molecular weight is measured by gel permeation chromatography, and a value converted to standard polystyrene is used.

  Examples of the binder polymer (A) include acrylic resins, styrene resins, epoxy resins, amide resins, amide epoxy resins, alkyd resins, and phenol resins. Of these, acrylic resins are preferred from the standpoint of alkali developability. These can be used alone or in combination of two or more.

  The (A) binder polymer can be produced, for example, by radical polymerization of a polymerizable monomer. Examples of the polymerizable monomer include polymerizable styrene derivatives such as styrene, vinyl toluene, α-methyl styrene, p-methyl styrene, and p-ethyl styrene, and vinyl alcohols such as acrylamide, acrylonitrile, and vinyl n-butyl ether. Esters, (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 (meth) acrylate, (meth) acrylic acid, α-bromo (meth) acrylic acid, α-chloro (meth) acrylic Acid, β-furyl ( T) Acrylic acid, β-styryl (meth) acrylic acid, maleic acid, maleic anhydride, maleic acid monoester such as monomethyl maleate, monoethyl maleate, monoisopropyl maleate, fumaric acid, cinnamic acid, α- Examples thereof include cyanocinnamic acid, itaconic acid, crotonic acid, and propiolic acid. These can be used alone or in combination of two or more.

  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. These can be used alone or in combination of two or more.

  The binder polymer (A) preferably contains a carboxyl group from the viewpoint of alkali developability, and 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.

  Moreover, it is preferable that the said (A) binder polymer contains styrene and / or a styrene derivative as a monomer unit from the viewpoint of adhesiveness, peeling characteristics, and chemical resistance (plating resistance).

  In order to obtain a binder polymer having good adhesion, peeling properties and chemical resistance (plating resistance) using the styrene and / or styrene derivative as a monomer, the styrene and / or styrene derivative based on the total amount of the monomer is used. The blending amount is preferably 3 to 30% by mass, more preferably 4 to 28% by mass, and particularly preferably 5 to 27% by mass. If the blending amount is less than 3% by mass, the adhesion tends to be inferior, and if it exceeds 30% by mass, the peel piece tends to be large and the peel time tends to be long.

  The acid value of the (A) binder polymer is preferably 30 to 200 mgKOH / g, and more preferably 45 to 150 mgKOH / g. When the acid value is less than 30 mg KOH / g, the development time tends to be long, and when it exceeds 200 mg KOH / g, the developer resistance of the photocured resist tends to be lowered. Moreover, when performing solvent development at the time of image development, it is preferable to prepare the polymerizable monomer which has a carboxyl group in a small quantity.

  Moreover, the said (A) binder polymer may have a photosensitive group as needed.

  These binder polymers can be used alone or in combination of two or more. As a binder polymer in the case of using two or more types in combination, for example, two or more types of binder polymers composed of different copolymerization components, two or more types of binder polymers having different 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.

  Moreover, when using 2 or more components of binder polymer, the weight average molecular weight of the binder polymer with the largest compounding amount should just be 10,000-100,000.

  The first photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond in the molecule as the component (B1) is not particularly limited, but the oxyalkylene having 2 to 6 carbon atoms in the molecule is not limited. A compound having 4 to 40 groups is preferable.

  Examples of the oxyalkylene group having 2 to 6 carbon atoms include oxyethylene group, oxypropylene group, oxyisopropylene group, oxybutylene group, oxypentylene group, oxyhexylene group, etc., but resolution and plating resistance From this point, an oxyethylene group or an oxyisopropylene group is preferable.

  Among these (B1) first photopolymerizable compounds, for example, bisphenol A-based (meth) acrylate compounds or polyalkylene glycol di (meth) acrylates can be particularly preferably used.

  As said bisphenol A type (meth) acrylate compound, the compound represented by the said General formula (1) is mentioned preferably, for example.

In the general formula (1), R ¹ and R ² each independently represent a hydrogen atom or a methyl group, and preferably a methyl group. In the general formula (1), X ¹ and Y ¹ each independently represent an alkylene group having 2 to 6 carbon atoms, preferably an ethylene group or a propylene group, and more preferably an ethylene group. In the general formula (1), p and q are positive integers selected so that p + q = 4 to 40, preferably p + q = 6 to 34, and more preferably p + q = 8 to 30. Preferably, p + q = 8 to 28, more preferably p + q = 8 to 20, particularly preferably p + q = 8 to 16, and most preferably p + q = 8 to 12. When p + q is less than 4, the compatibility with (A) the binder polymer is lowered, and when the photosensitive element is laminated on the circuit forming substrate, it tends to be peeled off. When p + q exceeds 40, the hydrophilicity is increased. The resist image tends to be peeled off during development, and the plating resistance against solder plating or the like tends to decrease.

  Examples of the alkylene group having 2 to 6 carbon atoms include an ethylene group, a propylene group, an isopropylene group, a butylene group, a pentylene group, a hexylene group, and the like. Groups are preferred.

  The aromatic ring in the general formula (1) may have a substituent, and examples of the substituent include a halogen atom, an alkyl group having 1 to 20 carbon atoms, and a cyclohexane having 3 to 10 carbon atoms. Alkyl group, aryl group having 6 to 18 carbon atoms, phenacyl group, amino group, alkylamino group having 1 to 10 carbon atoms, dialkylamino group having 2 to 20 carbon atoms, nitro group, cyano group, carbonyl group, mercapto group, A C1-C10 alkyl mercapto group, an allyl group, a hydroxyl group, a C1-C20 hydroxyalkyl group, a carboxyl group, a C1-C10 carboxyalkyl group, and a C1-C10 alkyl group. 10 acyl groups, C1-C20 alkoxy groups, C1-C20 alkoxycarbonyl groups, C2-C10 alkylcarbonyl groups, C2-C10 alkyls Alkenyl group, N- alkylcarbamoyl group or a group containing a heterocyclic ring having 2 to 10 carbon atoms, an aryl group substituted by these substituents. The above substituents may form a condensed ring. Moreover, the hydrogen atom in these substituents may be substituted with the above substituents such as a halogen atom. When the number of substituents is 2 or more, each of the two or more substituents may be the same or different.

  Examples of the compound represented by the general formula (1) include 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane, 2,2-bis (4-((meth) acrylic). Loxypolypropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxypolybutoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxypolyethoxypolypropoxy) phenyl) Examples thereof include bisphenol A-based (meth) acrylate compounds such as propane.

  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), 2,2-bis (4-((meth) acryloxyundecaethoxy) phenyl), 2,2 -Bis (4-((meth) acryloxydodecaethoxy) phenyl), 2,2-bis (4-((meth) acryloxytridecaethoxy) phenyl), 2,2-bis (4-((meth)) (Acryloxytetradecaethoxy) phenyl), 2,2-bis (4-((meth) acryloxypentadecaethoxy) phenyl), 2,2-bis (4-((meth) acryloxyhexadecaethoxy) phenyl) 2,2-bis (4- (methacryloxypentaethoxy) phenyl) propane is commercially available as BPE-500 (product name, manufactured by Shin-Nakamura Chemical Co., Ltd.). Are possible, 2,2-bis (4- (methacryloxy pentadecanoyl) phenyl) is, BPE-1300 (manufactured by Shin-Nakamura Chemical Co., Ltd., product name) is commercially available as. These may be used alone or in combination of two or more.

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

  As said polyalkylene glycol di (meth) acrylate, the compound represented by the said General formula (2) is mentioned preferably, for example.

In the general formula (2), R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and is preferably a methyl group. In the general formula (2), X ² , X ³ and Y ² each independently represent an alkylene group having 2 to 6 carbon atoms, and preferably an ethylene group or a propylene group. In the general formula (2), s, t and u are integers of 0 to 30 selected so that s + t + u = 4 to 40, preferably s + t + u = 5 to 30, and s + t + u = 8 to 23 More preferably, it is particularly preferable that s + t + u = 10-15. If the s + t + u is less than 4, the boiling point of the compound is lowered, so that the odor of the photosensitive layer tends to be strong. There is no tendency.

In addition, the oxyalkylene group (— (Y ¹ —O) _s —, — (Y ² —O) _t —, and — (Y ³ —O) _u —) in the general formula (2) is, for example, When an oxyethylene group and an oxypropylene group are included, a plurality of the oxyethylene group and the oxypropylene group do not need to be continuously present in blocks, and may be present randomly. .

  Furthermore, when the oxyalkylene group is an oxyisopropylene group, the secondary carbon of the propylene group may be bonded to an oxygen atom, or the primary carbon may be bonded to an oxygen atom.

  Preferable examples of the compound represented by the general formula (2) include compounds represented by the following general formulas (3) to (5). In addition, these can be used individually or in combination of 2 or more types.

［式中、Ｒ^３及びＲ^４はそれぞれ独立に水素原子又は炭素数１〜３のアルキル基を示し、ＥＯはエチレングリコール基を示し、ＰＯはプロピレングリコール基を示し、ｍ^１、ｍ^２及びｎ^１はｍ^１＋ｍ^２＋ｎ^１＝４〜４０となるように選ばれる１〜３０の整数を示す。］

[Wherein, R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, EO represents an ethylene glycol group, PO represents a propylene glycol group, m ¹ , m ² and n ¹ represents an integer of 1 to 30 to be selected so that ^{m 1 + m 2 + n 1} = 4~40. ]

［式中、Ｒ^３及びＲ^４はそれぞれ独立に水素原子又は炭素数１〜３のアルキル基を示し、ＥＯはエチレングリコール基を示し、ＰＯはプロピレングリコール基を示し、ｍ^３、ｎ^２及びｎ^３はｍ^３＋ｎ^２＋ｎ^３＝４〜４０となるように選ばれる１〜３０の整数を示す。］

[Wherein, R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, EO represents an ethylene glycol group, PO represents a propylene glycol group, m ³ , n ² and n ³ is an integer of 1 to 30 to be selected so that ^{m 3 + n 2 + n 3} = 4~40. ]

［式中、Ｒ^３及びＲ^４はそれぞれ独立に水素原子又は炭素数１〜３のアルキル基を示し、ＥＯはエチレングリコール基を示し、ＰＯはプロピレングリコール基を示し、ｍ^４及びｎ^４はｍ^４＋ｎ^４＝４〜４０となるように選ばれる１〜３０の整数を示す。］

[Wherein R ³ and R ⁴ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, EO represents an ethylene glycol group, PO represents a propylene glycol group, and m ⁴ and n ⁴ represent m ⁴ + ⁿ indicates the 30 integer selected to 4 = 4-40 and so as. ]

  Examples of the alkyl group having 1 to 3 carbon atoms in the general formulas (3) to (5) include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group.

The total number of repeating ethylene glycol groups (m ¹ + m ² , m ³ and m ⁴ ) in the general formulas (3) to (5) is preferably an integer of 1 to 30, and preferably an integer of 1 to 10. It is more preferable that it is an integer of 4-9, and it is especially preferable that it is an integer of 5-8. If the number of repetitions exceeds 30, the tent reliability and the resist shape tend to deteriorate.

The total number of repeating propylene glycol groups (n ¹ , n ² + n ³ and n ⁴ ) in the general formulas (3) to (5) is preferably an integer of 1 to 30, and an integer of 5 to 20 It is more preferable that it is an integer of 8-16, and it is especially preferable that it is an integer of 10-14. If the number of repetitions exceeds 30, the resolution deteriorates and sludge tends to be generated.

Specific examples of the compound represented by the general formula (3) include, for example, vinyl in which R ³ and R ⁴ are methyl groups, m ¹ + m ² = 4 (average value), and n ¹ = 12 (average value). Compound (manufactured by Hitachi Chemical Co., Ltd., trade name: FA-023M) and the like.

Specific examples of the compound represented by the general formula (4) include, for example, vinyl in which R ³ and R ⁴ are methyl groups, m ³ = 6 (average value), and n ² + n ³ = 12 (average value). Compound (manufactured by Hitachi Chemical Co., Ltd., trade name: FA-024M) and the like.

Specific examples of the compound represented by the general formula (5) include a vinyl compound in which R ³ and R ⁴ are hydrogen atoms, m ⁴ = 1 (average value), and n ⁴ = 9 (average value) ( Shin-Nakamura Chemical Co., Ltd., sample name: NK ester HEMA-9P) and the like.

  These may be used alone or in combination of two or more.

  (B1) As the first photopolymerizable compound, in addition to the photopolymerizable compound having an ethylenically unsaturated bond as described above, it further contains a photopolymerizable compound having another ethylenically unsaturated bond. For example, nonylphenoxypolyalkyleneoxy (meth) acrylate such as nonylphenoxypolyethyleneoxy (meth) acrylate, nonylphenoxypolypropyleneoxy (meth) acrylate, nonylphenoxypolyethyleneoxypolypropyleneoxy (meth) acrylate, γ-chloro Phthalic compounds such as -β-hydroxypropyl-β '-(meth) acryloyloxyethyl-o-phthalate, β-hydroxyalkyl-β'-(meth) acryloyloxyalkyl-o-phthalate, (meth) acrylic acid Alkyl beauty treatment salon And the like.

  The photosensitive layer 14 can contain a photopolymerizable compound other than the above-mentioned (B1) first photopolymerizable compound. For example, an α, β-unsaturated carboxylic acid is reacted with a glycidyl group-containing compound. And a urethane monomer such as a (meth) acrylate compound having a urethane bond in the molecule.

  Examples of the first photopolymerization initiator that is the component (C1) include N, N′-tetraalkyl-4 such as benzophenone, N, N′-tetramethyl-4,4′-diaminobenzophenone (Michler ketone), and the like. , 4'-diaminobenzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propanone- Aromatic ketones such as 1, quinones such as alkyl anthraquinones, 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-chloropheny ) -4,5-di (methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole Dimer, 2,4,5-triarylimidazole dimer such as 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, 9-phenylacridine, 1,7-bis (9, 9'-acridinyl) heptane and other acridine derivatives, N-phenylglycine, N-phenylglycine derivatives, coumarin compounds and the like. Further, the substituents of the aryl groups of two 2,4,5-triarylimidazoles may be the same to give the target compound, or differently give an asymmetric compound. From the viewpoint of adhesion and sensitivity, 2,4,5-triarylimidazole dimer is more preferable. These are used alone or in combination of two or more.

  In the photosensitive layer 14, the blending amount of the (A) binder polymer is preferably 40 to 70 parts by mass, and 50 to 60 parts by mass with 100 parts by mass of the total amount of the components (A) and (B1). Is more preferable. If this amount is less than 40 parts by mass, the resolution and photosensitivity tend to be insufficient, and if it exceeds 70 parts by mass, the photocured product tends to be brittle.

  In addition, the blending amount of the (B1) first photopolymerizable compound is preferably 30 to 60 parts by mass, and 40 to 50 parts by mass with the total amount of the component (A) and the component (B1) being 100 parts by mass. It is more preferable that If this amount is less than 30 parts by mass, the photocured product tends to be brittle, and if it exceeds 60 parts by mass, the resolution and photosensitivity tend to be insufficient.

  Furthermore, it is preferable that the compounding quantity of (C1) 1st photoinitiator is 0.1-20 mass parts with respect to 100 mass parts of total amounts of (A) component and (B1) component. It is more preferable that it is 2-10 mass parts. If the blending amount is less than 0.1 parts by mass, the photosensitivity tends to be insufficient, and if it exceeds 20 parts by mass, the absorption on the surface of the composition increases during exposure and the internal photocuring is insufficient. Tend to be.

  Further, the photosensitive layer 14 may contain an additive other than the above components (A) to (C1) (hereinafter sometimes referred to as “(D1) component”). As this (D1) additive, for example, a photopolymerizable compound (oxetane compound etc.) having at least one cationically polymerizable cyclic ether group in the molecule, a cationic polymerization initiator, a dye such as malachite green, tribromophenyl, etc. Photochromic agents such as sulfone and leuco crystal violet, thermochromic inhibitors, plasticizers such as p-toluenesulfonamide, pigments, fillers, antifoaming agents, flame retardants, stabilizers, adhesion-imparting agents, leveling agents, peeling Accelerators, antioxidants, fragrances, imaging agents, thermal crosslinking agents and the like can be mentioned. These can be contained in an amount of about 0.01 to 20 parts by mass per 100 parts by mass of the total amount of the component (A) and the component (B1). These may be used alone or in combination of two or more.

  The photosensitive resin composition comprising the components (A) to (D1) for forming the photosensitive layer 14 may be methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N, as necessary. -It can melt | dissolve in solvents, such as dimethylformamide and propylene glycol monomethyl ether, or these mixed solvents, and can use it as a solution of about 30-60 mass% of solid content, and can form a photosensitive layer.

  The thickness of the photosensitive layer 14 needs to be 10 μm or less. Here, the upper limit value of the thickness of the photosensitive layer 14 is preferably 8 μm, more preferably 6 μm, and particularly preferably 3 μm. On the other hand, the lower limit of the thickness of the photosensitive layer 14 is preferably 1 μm and particularly preferably 2 μm. When this thickness exceeds 10 μm, there is a tendency that sufficient resolution cannot be obtained.

  The cushion layer 12 includes a second photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond (hereinafter sometimes referred to as “component (B2)”) and a second photopolymerizable initiator (hereinafter, referred to as “component”). In some cases, it is a layer containing “(C2) component”.

  When the cushion layer 12 contains the component (B2) and the component (C2), the component (B1) and the component (C1) included in the photosensitive layer 14 are sufficiently prevented from moving to the cushion layer 12. Thus, the photosensitive element 1 can obtain sufficient aging stability. When these (B2) component and (C2) component are not included in the cushion layer 12, a material having a particularly small molecular weight tends to move from the photosensitive layer 14 to the cushion layer 12, and the characteristics of the photosensitive element 1 tend to deteriorate. There is.

  Here, as the (B2) second photopolymerizable compound, the same photopolymerizable compound as that described above can be used. Moreover, as said (C2) 2nd photoinitiator, the thing similar to the 1st photoinitiator mentioned above can be used. These second photopolymerizable compound and second photopolymerization initiator may be the same as or different from the first photopolymerizable compound and first photopolymerization initiator, respectively. In addition, from the viewpoint of obtaining more sufficient aging stability, the second photopolymerizable compound and the second photopolymerization initiator include the material and the first photopolymerization initiator included in the first photopolymerizable compound. It is preferable to contain each of the materials contained in.

  The cushion layer 12 preferably contains a copolymer of ethylene and a monomer copolymerizable with the ethylene. The copolymer is preferably an ethylene-vinyl acetate copolymer and / or an ethylene-ethyl (meth) acrylate copolymer.

  Here, the proportion of the ethylene component based on the total amount of the monomer component in the ethylene-vinyl acetate copolymer, and the proportion of the ethylene component based on the total amount of the monomer component in the ethylene-ethyl (meth) acrylate copolymer are: These are all preferably 60 to 90% by mass, more preferably 60 to 80% by mass, and particularly preferably 60 to 70% by mass. When the ethylene ratio is less than 60% by mass, the adhesiveness between the cushion layer 12 and the photosensitive layer 14 becomes too high even when any copolymer is used, and the peeling tends to be difficult. On the other hand, when the proportion of ethylene exceeds 90% by mass, the adhesiveness between the cushion layer 12 and the photosensitive layer 14 becomes too small regardless of which copolymer is used, and the photosensitive film 1 including the cushion layer 12 is produced. Tend to be difficult to do.

  Further, the cushion layer 12 may contain an additive (hereinafter, sometimes referred to as “component (D2)”). The (D2) additive is the same as the (D1) additive in the photosensitive layer 14 described above. Can be used.

  The thickness of the cushion layer 12 is preferably 1 to 100 μm, more preferably 10 to 50 μm, and particularly preferably 15 to 40 μm. If the thickness is less than 1 μm, the followability to the unevenness of the surface of the object to be laminated tends to decrease, and if it exceeds 100 μm, the cost tends to increase.

  The photosensitive element 1 preferably further includes a protective film on the photosensitive layer 14 (on F1). Here, FIG. 3 is a schematic cross-sectional view showing another preferred embodiment of the photosensitive element of the present invention. The photosensitive element 2 shown in FIG. 3 has a structure in which a cushion layer 12, a photosensitive layer 14, and a protective film 16 are sequentially laminated on a support film 10.

  Since the protective film 16 is peeled off before the photosensitive element 1 is laminated on the substrate, the protective film 16 is flexible and can be peelably bonded to the photosensitive layer 14 and is not damaged at the temperature of the drying furnace. Preferably there is. Examples of the protective film 16 include paper, release paper, polyester such as polyethylene terephthalate, polyolefin such as polymethylpentene, polypropylene, and polyethylene, halogen-containing vinyl polymers such as polyvinyl fluoride and polyvinyl chloride, nylon, and the like. Examples of the film include cellulose such as polyamide and cellophane, and films such as polystyrene. These may be transparent or non-transparent, and may be subjected to a release treatment. Examples of the commercially available protective film 16 include E-200H (trade name) manufactured by Oji Paper Co., Ltd. and NF-13 (trade name) manufactured by Tamapoli Co., Ltd.

  The thickness of the protective film 16 is not particularly limited, but considering the size when the photosensitive element 1 is rolled up, it is preferably 10 to 30 μm, more preferably 10 to 25 μm, It is especially preferable to set it as 10-20 micrometers.

  The relationship between the interlayer adhesive force between the cushion layer 12, the support film 10 and the photosensitive layer 12 is that the interlayer adhesive force (a1) between the support film 10 and the cushion layer 12 is different between the cushion layer 12 and the photosensitive layer 14. It is preferably larger than the interlayer adhesive force (a2) between them, and this allows easy separation between the cushion layer 12 and the photosensitive layer 14.

  When the protective film 16 is provided on the photosensitive layer 14, the interlayer adhesive force (a3) between the protective film 16 and the photosensitive layer 14 is the interlayer adhesive force between the cushion layer 12 and the photosensitive layer 14 ( It is preferable to be smaller than a2), which makes it easy to peel off the protective film 16 and the photosensitive layer 14.

  The interlayer adhesive strength can be measured as 180 ° peel strength under the conditions of a temperature of 23 ° C. and a humidity of 60% using a rheometer or the like.

  Here, the ratio of the interlayer adhesive force (a1) between the support film 10 and the cushion layer 12 to the interlayer adhesive force (a2) between the cushion layer 12 and the photosensitive layer 14 is the value {(a1) / (a2)}. The ratio {(a2) / (a3)} of the interlayer adhesive force between the cushion layer 12 and the photosensitive layer 14 to the interlayer adhesive force (a3) between the protective film and the photosensitive layer 14 is 1 It is preferably 0.05 or more, more preferably 1.5 or more, and particularly preferably 2.0 or more. When the ratio of these interlayer adhesive strengths is less than 1.05, there is a tendency to peel off between layers different from the desired layer.

  The method for laminating the cushion layer 12 and the photosensitive layer 14 on the support film 10 is not particularly limited. For example, (1) the cushion layer 12 is laminated on the support film 10 and then the photosensitive layer 14 is laminated. Method, (2) Method of simultaneously laminating cushion layer 12 and photosensitive layer 14 on support film 10, (3) Laminating cushion layer 12 on support film 10, and photosensitive layer 14 on protective film 16 (4) A method of laminating the photosensitive layer on the protective film 16 and then laminating the cushion layer 12 and the support film 10 in sequence, (5) a method of laminating the photosensitive layer 14 and the cushion layer on the protective film 16 12 and the like, and then a method of laminating the support film 10. Among these, the method (3) is preferable from the viewpoint of improving the yield at the time of producing the resist pattern.

  The photosensitive element 1 thus obtained can be stored in a roll shape. In addition to the support film 10, the cushion layer 12, and the photosensitive layer 14, the photosensitive element 1 is protected separately from an intermediate layer such as an adhesive layer, a light absorption layer, a gas barrier layer, and the protective film 16 as necessary. It may have a layer.

  The photosensitive layer 14 preferably has a transmittance for ultraviolet rays having a wavelength of 365 nm of 5 to 75%, more preferably 7 to 60%, and particularly preferably 10 to 40%. If the transmittance is less than 5%, the adhesion tends to be inferior, and if it exceeds 75%, the resolution tends to be inferior. The transmittance can be measured by a UV spectrometer, and examples of the UV spectrometer include a 228A type W beam spectrophotometer manufactured by Hitachi, Ltd.

  Next, the resist pattern forming method of the present invention will be described with reference to FIGS.

  2A to 2E are a series of process diagrams showing a preferred embodiment of the resist pattern forming method of the present invention. First, as shown in FIG. 2A, the photosensitive element 1 in which the support film 10, the cushion layer 12, and the photosensitive layer 14 are laminated in this order on the surface of the circuit forming substrate 18, the photosensitive layer 14 The roller 20 is used for pressure bonding so as to contact the circuit forming substrate 18, and the photosensitive layer 14, the cushion layer 12, and the base film 10 are laminated in this order on the circuit forming substrate 18 as shown in FIG. A laminating process is performed. In addition, when the photosensitive element 1 has a protective film on the photosensitive layer 14, a lamination process is performed after peeling a protective film. Next, as shown in FIG. 2C, a peeling process for peeling the cushion layer 12 and the support film 10 is performed to obtain a laminated substrate having the photosensitive layer 14 on the circuit forming substrate 18.

  Next, as shown in FIG. 2D, by using a pattern mask 22 having a transparent portion with respect to actinic rays such as ultraviolet rays, a predetermined portion of the photosensitive layer 14 in the laminated substrate is irradiated with actinic rays. An exposure process for forming a photocured portion is performed. Then, as shown in FIG. 2E, a developing process for removing the photosensitive layer 14 other than the photocured portion is performed to form a resist pattern 24.

In the above laminating step, as a method of laminating the photosensitive layer 14 on the circuit forming substrate 18, for example, while the photosensitive layer 14 is heated to about 70 to 130 ° C., about 0.1 to 1 MPa is applied to the circuit forming substrate 18. The method of laminating | stacking by crimping with the pressure (about 1-10 kgf / cm < ² >) is mentioned. At this time, lamination may be performed under reduced pressure from the viewpoint of adhesion and followability. In addition, in order to further improve the stackability, the circuit forming substrate 18 may be preheated. The surface on which the circuit forming substrate 18 is laminated is usually a metal surface, but is not particularly limited. Furthermore, unevenness may exist on the surface of the circuit forming substrate 18, and by using the photosensitive element 1 of the present invention, lamination can be performed with good conformity to the unevenness.

  In the photosensitive element 1 thus laminated, the support film 10 and the cushion layer 12 are removed from the photosensitive layer 14 in the peeling step. Thereafter, in the exposure process, the photosensitive layer 14 is irradiated with an actinic ray in an image form through a negative or positive pattern mask 22 called an artwork. As the light source of actinic light, a known light source such as a carbon arc lamp, a mercury vapor arc lamp, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, or a xenon lamp that emits ultraviolet rays effectively is used. Moreover, what emits visible light effectively, such as a photographic flood light bulb and a solar lamp, is also used.

  The development step is performed by removing a non-exposed portion (uncured portion) by wet development, dry development or the like and developing it to form a resist pattern. In the case of wet development, a developer corresponding to a photosensitive resin composition such as an alkaline aqueous solution, an aqueous developer, an organic solvent developer, or the like, for example, a known method such as spraying, rocking immersion, brushing, or scraping is used. Develop by method.

  As the developing solution, a safe and stable solution having good operability such as an alkaline aqueous solution is used. Examples of the base of the alkaline aqueous solution include alkali hydroxides such as lithium, sodium, or potassium hydroxide, alkali carbonates such as lithium, sodium, potassium, or ammonium carbonate or bicarbonate, potassium phosphate, and phosphoric acid. Alkali metal phosphates such as sodium and alkali metal pyrophosphates such as sodium pyrophosphate and potassium pyrophosphate are used. Moreover, as alkaline aqueous solution used for image development, 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, A dilute solution of 0.1 to 5% by mass sodium tetraborate is preferred. The pH of the alkaline aqueous solution used for development is preferably in the range of 9 to 11, and the temperature is adjusted according to the developability of the photosensitive resin composition layer 14. In the alkaline aqueous solution, a surfactant, an antifoaming agent, a small amount of an organic solvent for accelerating development, and the like may be mixed.

  The aqueous developer is composed of water or an aqueous alkaline solution and one or more organic solvents. Here, as the base of the alkaline aqueous solution in the aqueous developer, in addition to the above-mentioned bases, 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 can be mentioned. The pH of the developer is preferably 8 to 12 and more preferably 9 to 10 within a range where the resist can be sufficiently developed.

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

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

  In the development step, two or more development methods may be used in combination as necessary. Development methods include a dip method, a battle method, a spray method, brushing, and slapping, and the high pressure spray method is most suitable for improving the resolution.

As the treatment after development, the resist pattern may be further cured and used by heating at about 60 to 250 ° C. or exposure at about 0.2 to 10 mJ / cm ² as necessary.

  In the method for producing a printed wiring board of the present invention, the circuit forming substrate on which the resist pattern is formed is etched or plated by the resist pattern forming method of the present invention.

  Etching or plating the circuit forming substrate is performed by etching or plating the surface of the circuit forming substrate by a conventionally known method using the developed resist pattern as a mask.

  As the etching solution used for the above etching, for example, a cupric chloride solution, a ferric chloride solution, an alkaline etching solution, a hydrogen peroxide-based etching solution, and the like can be used. It is preferable to use a ferric solution.

  Examples of the plating method for performing the above 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 sulfamate plating, etc. Nickel plating, hard gold plating, and gold plating such as soft gold plating.

  After etching or plating, the resist pattern can be peeled off with a stronger alkaline aqueous solution than the alkaline aqueous solution used for development, for example. As this strongly alkaline aqueous solution, for example, a 1 to 10% by mass sodium hydroxide aqueous solution, a 1 to 10% by mass potassium hydroxide aqueous solution and the like are used. Examples of the peeling method include a dipping method and a spray method, and the dipping method and the spray method may be used alone or in combination. The printed wiring board on which the resist pattern is formed may be a multilayer printed wiring board.

  Further, when the plating is performed on a circuit forming substrate including an insulating layer and a conductor layer formed on the insulating layer, it is necessary to remove the conductor layer other than the pattern. As this removal method, for example, a method of lightly etching after removing the resist pattern, or performing solder plating after the above plating, and then masking the wiring portion with solder by peeling off the resist pattern, and then conducting layer The method etc. which process using the etching liquid which can etch only are mentioned.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

[Synthesis of Binder Polymer A]
Into a flask equipped with a stirrer, reflux condenser, thermometer, dropping funnel and nitrogen gas introduction tube, 350 g of a mixture of methyl cellosolve / toluene (mass ratio: 3/2) was added and stirred while blowing nitrogen gas. And heated to 80 ° C. On the other hand, a solution (hereinafter referred to as “solution a”) prepared by mixing 150 g of methacrylic acid, 300 g of methyl methacrylate and 150 g of styrene and 9.0 g of azobisisobutyronitrile as a comonomer was prepared. Next, the solution a was added dropwise to the methyl cellosolve / toluene mixture (mass ratio: 3/2) heated to 80 ° C. over 4 hours, and then kept at 80 ° C. with stirring for 2 hours. Furthermore, a solution in which 1.2 g of azobisisobutyronitrile was dissolved in 50 g of a mixed solution of methyl cellosolve / toluene (mass ratio: 3/2) was dropped into the flask over 10 minutes. The solution after dropping was kept at 80 ° C. for 3 hours with stirring, and then heated to 90 ° C. over 30 minutes. The mixture was kept at 90 ° C. for 2 hours and then cooled to obtain a solution of binder polymer A. The non-volatile content (solid content) of the binder polymer A solution was 60% by mass, and the weight average molecular weight of the binder polymer A was 20,000. The weight average molecular weight was measured by a gel permeation chromatography method and was derived by conversion using a standard polystyrene calibration curve. The GPC conditions are as follows.

(GPC conditions)
Pump: Hitachi L-6000 type (manufactured by Hitachi, Ltd., trade name)
Column: Gelpack GL-R420 + Gelpack GL-R430 + Gelpack GL-R440 (3 in total) (above, manufactured by Hitachi Chemical Co., Ltd., trade name)
Eluent: Tetrahydrofuran Measurement temperature: 25 ° C
Flow rate: 2.05 mL / min Detector: Hitachi L-3300 RI (trade name, manufactured by Hitachi, Ltd.)

[Synthesis of Binder Polymer B]
Synthesis was performed in the same manner as the synthesis of the binder polymer A except that the amount of azobisisobutyronitrile added in the solution a was 3.0 g, and a solution of the binder polymer B was obtained. The nonvolatile content (solid content) of the solution of the binder polymer B was 60% by mass, and the weight average molecular weight of the binder polymer B was 60,000.

[Synthesis of Binder Polymer C]
First, the amount of the mixture of methyl cellosolve / toluene (mass ratio: 3/2) placed in the flask was 550 g, and the amount of azobisisobutyronitrile added in the solution a was 0.6 g. Synthesis was performed by the same method as the synthesis of polymer A to obtain a solution of binder polymer C. The nonvolatile content (solid content) of the solution of the binder polymer C was 50% by mass, and the weight average molecular weight of the binder polymer C was 150,000.

  The weight average molecular weights and acid values of the binder polymers A, B and C are shown together in Table 1.

[Production of photosensitive layer material]
The materials shown in Table 2 were blended to prepare photosensitive layer materials (I), (II) and (III). In addition, the unit of the compounding quantity of each material in Table 2 is a mass part.

[Production of cushion layer material]
Cushion layer materials (I), (II), (III) and (IV) were prepared by blending the materials shown in Table 3. In addition, the unit of the compounding quantity of each material in Table 3 is a mass part.

(Examples 1-3 and Comparative Examples 1-2)
[Production of photosensitive element]
In Example 1, a photosensitive element was produced in the following procedure by combining the photosensitive layer material (I) and the cushion layer material (II).

  First, as a support film, a 16 μm thick polyethylene terephthalate (PET) film (trade name: G2-16, manufactured by Teijin Ltd.) is prepared, and the cushion layer material (II) is formed thereon with a thickness after drying. It was applied uniformly to a thickness of 10 μm and dried for 10 minutes with a hot air convection dryer at 115 ° C. to form a cushion layer. Next, the photosensitive layer material (I) was uniformly applied onto the cushion layer so that the thickness after drying was 10 μm, and dried for 10 minutes with a hot air convection dryer at 100 ° C. to form a photosensitive layer. Thereafter, a biaxially stretched polypropylene film (trade name: E-200H, manufactured by Oji Paper Co., Ltd.) having a thickness of 20 μm was prepared as a protective film, and this was laminated on the photosensitive layer to form the photosensitive element of Example 1. Obtained. The resulting photosensitive element was wound up with the support film on the outside.

  In Example 2, the photosensitive layer material (I) and the cushion layer material (II) are used in combination, and the thickness of the cushion layer is 20 μm. In Example 3, the photosensitive layer material (II) and the cushion layer material are used. (II) is used in combination and the thickness of the cushion layer is 20 μm. In Comparative Example 1, the photosensitive layer material (I) and the cushion layer material (II) are used in combination and the thickness of the cushion layer and the photosensitive layer is used. In Comparative Example 2, the photosensitive layer material (I) and the cushion layer material (IV) were used in combination and the thickness of the cushion layer was 20 μm. The photosensitive elements of Examples 2-3 and Comparative Examples 1-2 were obtained.

(Examples 4-9 and Comparative Examples 3-8)
[Production of photosensitive element]
In Example 4, a photosensitive element was produced in the following procedure by combining the photosensitive layer material (I) and the cushion layer material (I).

  First, as a support film, a polyethylene terephthalate (PET) film (trade name: G2-16, manufactured by Teijin Ltd.) having a thickness of 16 μm is prepared, and a cushion layer material (I) is formed thereon with a thickness after drying. It was applied uniformly to a thickness of 10 μm and dried for 10 minutes with a hot air convection dryer at 115 ° C. to form a cushion layer. Next, another 16 μm-thick PET film (trade name: G2-16, manufactured by Teijin Ltd.) is prepared, and the photosensitive layer material (I) is uniformly applied thereon so that the thickness after drying becomes 6 μm. It was applied and dried for 10 minutes with a hot air convection dryer at 100 ° C. to form a photosensitive layer. Then, it bonded together so that a cushion layer and a photosensitive layer might adhere | attach (so that a PET film might become an outer side), and the photosensitive element of Example 4 was obtained. In addition, let the PET film by the side of a photosensitive layer be a protective film.

  In Examples 5 to 9 and Comparative Examples 3 to 7, as shown in Tables 5 and 6, the same as Example 4 except that the material and film thickness of the photosensitive layer and the material and film thickness of the cushion layer were changed. A photosensitive element was prepared by the procedure described above. This obtained the photosensitive element of Examples 5-9 and Comparative Examples 3-7.

  In Comparative Example 8, a 16 μm thick PET film (trade name: G2-16, manufactured by Teijin Ltd.) is prepared, and the photosensitive layer material (I) is formed thereon so that the thickness after drying becomes 6 μm. And a photosensitive layer was formed by drying with a hot air convection dryer at 100 ° C. for 10 minutes. Thereafter, a biaxially stretched polypropylene film (trade name: E-200H, manufactured by Oji Paper Co., Ltd.) having a thickness of 20 μm was prepared as a protective film, and this was laminated on the photosensitive layer to obtain the photosensitive element of Comparative Example 8. Obtained.

[Production of Printed Wiring Board A (Evaluation of Adhesion and Resolution)]
Using each of the photosensitive elements of Examples 1 to 9 and Comparative Examples 1 to 8, a printed wiring board A was prepared by the following procedure, and adhesion and resolution were evaluated. In addition, the photosensitive element used within 12 hours after preparation.

  First, a polishing machine having a brush equivalent to # 600 (Sankei) on the copper surface of a glass epoxy substrate (trade name: MCL-E67-35S, manufactured by Hitachi Chemical Co., Ltd.) having a 35 μm thick copper foil laminated on one side. (Made by Co., Ltd.), washed with water, and dried by air flow to obtain a copper clad laminate.

  Next, after heating the obtained copper-clad laminate to 80 ° C., using a high-temperature laminator (manufactured by Hitachi Chemical Co., Ltd., HLM-3000), the protective film of the photosensitive element is applied to the copper-clad laminate. While peeling, the photosensitive layer was directed to the copper clad laminate and laminated with the support film side touching the roll.

  At this time, the laminating roll speed was 1.5 m / min, the laminating roll temperature was 110 ° C., and the cylinder pressure of the roll was 0.4 MPa.

  Next, after the lamination, the film was cooled to 23 ° C., and then the support film and the cushion layer of the photosensitive element were peeled off. In the case of the photosensitive element of Comparative Example 8, only the support film was peeled off.

  Next, a negative mask for resolution evaluation having a wiring pattern with a negative mask (Stofer 21-step tablet, line width / space width of 400/6 to 400/47 (unit: μm), and line width / space width of 6/400 21 steps on the stove using an exposure machine (model EXM-1201, mercury short arc lamp) manufactured by Oak Manufacturing Co., Ltd.) and a 47/400 (unit: μm) wiring evaluation negative mask having a wiring pattern) The tablet was exposed with an energy amount such that the number of steps remaining after development was 6.0.

  Subsequently, the photosensitive element was spray-developed with a 1% by mass aqueous sodium carbonate solution (30 ° C.) for the development times shown in Tables 4 to 6 (spray pressure: 0.18 MPa), and a resist pattern was formed on the copper-clad laminate. Formed.

  Here, the value of the minimum space width with no development residue of the resist pattern formed using the resolution evaluation negative mask is measured as the resolution, and the resist pattern formed using the adhesion evaluation negative mask causes meandering and chipping. The minimum resist width formed without any problem was measured as adhesion. The results are shown in Tables 4-6. In addition, it means that resolution and adhesiveness are excellent, so that this value is small.

[Production of Printed Wiring Board B (Evaluation of Conformity Follow-up)]
Using each of the photosensitive elements of Examples 1 to 9 and Comparative Examples 1 to 8, a printed wiring board B was produced by the following procedure, and the unevenness followability was evaluated. In addition, the photosensitive element used within 12 hours after preparation.

  First, RY-3210 (trade name, manufactured by Hitachi Chemical Co., Ltd.) was used as the photosensitive element, and a negative mask having a line width / space width of 1,000 / 100 (unit: μm) was used as the negative mask. In the same manner as in the production of the printed wiring board A, a copper-clad laminate having a resist pattern was obtained.

  Next, the obtained copper-clad laminate was immersed in a 100 g / L ammonium persulfate aqueous solution (30 ° C.) for 1 to 30 minutes. Further, the resist pattern was stripped (3 mass% sodium hydroxide aqueous solution, 50 ° C., spray pressure). : 0.18 MPa), and a substrate for evaluation of unevenness followability having an uneven portion with a recess depth of 1 to 15 μm and a recess width of 100 μm was obtained.

  After heating the obtained uneven | corrugated followable | trackable evaluation board | substrate to 80 degreeC, using a high temperature laminator (Hitachi Chemical Industry Co., Ltd. product, HLM-3000), peeling the protective film of the photosensitive element on the said board | substrate. The laminate was made with the photosensitive layer facing the substrate and the support film side touching the roll. At this time, the axis of the laminate roll and the length direction of the recessed portion of the substrate were made parallel. In this case, the laminating roll speed was 1.5 m / min, the laminating roll temperature was 110 ° C., and the cylinder pressure of the roll was 0.4 MPa.

  After the lamination, the film was cooled to 23 ° C., and then the support film and the cushion layer of the photosensitive element were peeled off. In the case of the photosensitive element of Comparative Example 8, only the support film was peeled off.

  Next, a negative mask (a stove 21 step tablet and a negative mask having a wiring pattern with a line width / space width of 100/100 (unit: μm)), and an exposure machine manufactured by Oak Manufacturing Co., Ltd. (model EXM-1201) , Mercury short arc lamp) was used, and exposure was performed with an energy amount such that the number of remaining steps after development of the stove 21-step tablet was 6.0.

  Subsequently, the photosensitive element was spray-developed with a 1% by mass aqueous sodium carbonate solution (30 ° C.) for the development times shown in Tables 4 to 6 (spray pressure: 0.18 MPa), and a resist pattern was formed on the copper-clad laminate. Formed.

Then, a cupric chloride etching solution (2 mol / L CuCl ₂ , 2N-HCL aqueous solution, 50 ° C.) is sprayed for 100 seconds (spray pressure: 0.2 MPa) to dissolve the copper that is not protected by the resist ( Etching), and further, the resist pattern is stripped with a stripping solution (3 mass% sodium hydroxide aqueous solution, 50 ° C., spray pressure: 0.2 MPa), and a copper wiring is formed on the substrate for evaluating unevenness followability Plate B was made.

  When the photosensitive element does not follow the uneven part on the unevenness follow-up evaluation substrate, a gap is generated between the resist and the substrate, so that the etching solution penetrates into the intersection of the resist and the recessed part, and the copper line Melts and the copper line is not connected, resulting in a disconnection failure. The depth (μm) of the dent where such disconnection failure was observed was measured as unevenness followability, and the results are shown in Tables 4-6. In addition, it means that uneven | corrugated followable | trackability is excellent, so that this value is large.

[Production of printed wiring board C (evaluation of stability over time)]
Using the photosensitive elements of Examples 1 to 9 and Comparative Examples 1 to 8, printed wiring boards C were produced according to the following procedure. At this time, the photosensitive element is used within 12 hours from the production, and the photosensitive element obtained after 30 days (stored in a dark place at 23 ° C. and 60% RH) is compared. Thus, the stability over time was evaluated.

  First, a polishing machine having a brush equivalent to # 600 (Sankei) on the copper surface of a glass epoxy substrate (trade name: MCL-E67-35S, manufactured by Hitachi Chemical Co., Ltd.) having a 35 μm thick copper foil laminated on one side. (Made by Co., Ltd.), washed with water, and dried by air flow to obtain a copper clad laminate.

  Next, after heating the obtained copper-clad laminate to 80 ° C., using a high-temperature laminator (manufactured by Hitachi Chemical Co., Ltd., HLM-3000), the protective film of the photosensitive element is applied to the copper-clad laminate. While peeling, the photosensitive layer was directed to the copper clad laminate and laminated with the support film side touching the roll.

  At this time, the laminating roll speed was 1.5 m / min, the laminating roll temperature was 110 ° C., and the cylinder pressure of the roll was 0.4 MPa.

  Next, after the lamination, the film was cooled to 23 ° C., and then the support film and the cushion layer of the photosensitive element were peeled off. In the case of the photosensitive element of Comparative Example 8, only the support film was peeled off.

  Next, a negative mask for resolution evaluation having a wiring pattern with a negative mask (Stofer 21-step tablet, line width / space width of 400/6 to 400/47 (unit: μm), and line width / space width of 6/400 Within 12 hours after production using an exposure machine (model EXM-1201, mercury short arc lamp) manufactured by Oak Manufacturing Co., Ltd., having a wiring pattern of .about.47 / 400 (unit: .mu.m). When the photosensitive element was used, exposure was performed with an energy amount such that the number of remaining step stages after development of the stove 21-step tablet was 6.0. The exposure energy amount when using the photosensitive element 30 days after the production was the same as the exposure energy amount within 12 hours after the production.

  Subsequently, the photosensitive element was spray-developed with a 1% by mass aqueous sodium carbonate solution (30 ° C.) for the development times shown in Tables 4 to 6 (spray pressure: 0.18 MPa), and a resist pattern was formed on the copper-clad laminate. Formed.

  Negative mask for resolution evaluation when using a photosensitive element within 12 hours after preparation and when using a photosensitive element that has been stored at room temperature (23 ° C., 60% RH) in a dark place for 30 days after preparation. The minimum resist width of a resist pattern formed by using the negative pattern for adhesion evaluation is measured without measuring the value of the minimum space width with no development residue and using a negative mask for adhesion evaluation. The width was measured as adhesion. In addition, it means that resolution and adhesiveness are excellent, so that this value is small. Also, the resolution and adhesion when using a photosensitive element within 12 hours after production were the same as the results obtained in [Production of Printed Wiring Board A (Evaluation of Adhesion and Resolution)]. Tables 4 to 6 show only the results when the photosensitive element after 30 days was used.

  In addition, the number of remaining steps was measured when using a photosensitive element that had been stored for 30 days after preparation (23 ° C., 60% RH, dark place). The results are shown in Tables 4-6. Here, the number of remaining steps in the case of using a photosensitive element within 12 hours after preparation and the case of using a photosensitive element that has been stored for 30 days after preparation (23 ° C., 60% RH, dark place) If it is the same (6.0) and no change in resolution and adhesion characteristics is observed, the stability over time is excellent, and if any of the number of remaining steps, resolution, or adhesion is different It can be evaluated that the stability over time is insufficient.

  As is clear from the results shown in Tables 4 to 6, the photosensitive elements of Examples 1 to 9 are superior in adhesion, resolution, and unevenness followability as compared to the photosensitive elements of Comparative Examples 1 to 8, It was confirmed that the stability over time was also good.

As described above, according to the present invention, a photosensitive element having sufficient followability with respect to the irregularities of the substrate surface to be laminated and having excellent adhesion, resolution, and stability over time, and the use thereof are used. A method for forming a resist pattern and a method for producing a printed wiring board can be provided.

Claims (17)

A support film, a cushion layer formed on the support film, and a photosensitive layer having a thickness of 10 μm or less formed on the cushion layer,
The photosensitive layer comprises a binder polymer having a weight average molecular weight of 10,000 to 100,000, a first photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond in the molecule, A layer containing a photopolymerization initiator,
The cushion layer is a layer comprising a second photopolymerizable compound having at least one polymerizable ethylenically unsaturated bond in the molecule and a second photopolymerization initiator. Sex element.   The photosensitive element according to claim 1, wherein the support film has a thickness of 5 to 20 μm.   The photosensitive element according to claim 1, wherein the binder polymer contains styrene and / or a styrene derivative as a monomer unit.   The photosensitive element according to any one of claims 1 to 3, wherein the binder polymer contains methacrylic acid as a monomer unit.   The photosensitive element according to claim 1, wherein an acid value of the binder polymer is 30 to 200 mg KOH / g.   6. The compound according to claim 1, wherein the first photopolymerizable compound and the second photopolymerizable compound include a compound having 4 to 40 oxyalkylene groups having 2 to 6 carbon atoms in the molecule. The photosensitive element as described in any one of them.   Among the first photopolymerizable compound and the second photopolymerizable compound, a bisphenol A-based (meth) acrylate compound or a polyalkylene glycol di (meth) acrylate is included. The photosensitive element as described in any one of these. The photosensitive element according to claim 7, wherein the bisphenol A-based (meth) acrylate compound is a compound represented by the following general formula (1).

[Wherein, R ¹ and R ² each independently represent a hydrogen atom or a methyl group, X ¹ and Y ¹ each independently represent an alkylene group having 2 to 6 carbon atoms, and p and q are p + q = 4 to 40 Indicates a positive integer chosen to be ] 8. The photosensitive element according to claim 7, wherein the polyalkylene glycol di (meth) acrylate is a compound represented by the following general formula (2).

[Wherein, R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, X ² , X ³ and Y ² each independently represent an alkylene group having 2 to 6 carbon atoms, s, t and u represent integers of 0 to 30 selected so that s + t + u = 4 to 40. ]   The said 1st photoinitiator and the said 2nd photoinitiator contain a 2,4,5-triaryl imidazole dimer, The any one of Claims 1-9 characterized by the above-mentioned. A photosensitive element as described in 1.   In the photosensitive layer, the blending amount of the first photopolymerizable compound is 30 to 60 parts by mass with the total amount of the binder polymer and the first photopolymerizable compound being 100 parts by mass, and the first light The blending amount of the polymerization initiator is 0.1 to 20 parts by mass with respect to 100 parts by mass of the total amount of the binder polymer and the first photopolymerizable compound. The photosensitive element as described in any one of Claims.   The photosensitive element according to any one of claims 1 to 11, wherein the cushion layer further contains a copolymer of ethylene and a monomer copolymerizable therewith.   The copolymer is an ethylene-vinyl acetate copolymer in which the proportion of ethylene based on the total amount of monomers is 60 to 90% by mass, or the proportion of ethylene based on the total amount of monomers is 60 to 90% by mass. The photosensitive film according to claim 12, which is an ethylene-ethyl (meth) acrylate copolymer.   The photosensitive element according to claim 1, wherein the cushion layer has a thickness of 1 to 100 μm.   The photosensitive element according to claim 1, further comprising a protective film that covers the photosensitive layer on the photosensitive layer. A laminating step of disposing the photosensitive element according to claim 1 so that the photosensitive layer, the cushion layer, and the support film are laminated on a circuit forming substrate in this order. ,
A peeling step of peeling the support film and the cushion layer from the photosensitive layer;
An exposure step of irradiating a predetermined portion of the photosensitive layer with actinic rays to form a photocured portion in the photosensitive layer;
A developing step for removing the photosensitive layer other than the photocured portion;
A method of forming a resist pattern, comprising:   A method for manufacturing a printed wiring board, comprising etching or plating a circuit forming substrate on which a resist pattern is formed by the method for forming a resist pattern according to claim 16.

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