JP2006227206A - Photosensitive element, resist pattern forming method using same and method for manufacturing printed wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive element which reduces the trailing amount of a resist pattern while having excellent resolution, and can form a resist pattern having a good shape of a lateral face thereof. <P>SOLUTION: The photosensitive element has on a resin film 10 a photosensitive layer 14 comprising a photosensitive resin composition containing (A) a binder polymer, (B) a photopolymerizable compound having an ethylenically unsaturated bond and (C) a photopolymerization initiator, wherein the component (A) has an acid number of 50-120 mgKOH/g and the resin film 10 has a haze of ≤1%. <P>COPYRIGHT: (C)2006,JPO&NCIPI

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, as a resist material used for etching, plating, etc. in the field of printed wiring board manufacturing or metal precision processing, a photosensitive resin composition or a layer made of this photosensitive resin composition (hereinafter referred to as “photosensitive layer”). ")" Is laminated on a resin film, and a photosensitive element having a structure in which a protective film is laminated on a photosensitive layer is widely used.

  As a method of using the photosensitive element, first, after the protective film is peeled off, the photosensitive layer is pressure-bonded (laminated) so that the photosensitive layer directly touches the base material (copper substrate or the like). Next, a patterned phototool is adhered onto the light-transmitting film, irradiated with an actinic ray such as ultraviolet rays (exposure), and then a developer is sprayed to remove the unexposed portions to form a resist pattern ( A method of developing) is common.

  As the developer 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, an alkali developing type using an aqueous sodium carbonate solution or an aqueous sodium hydrogen carbonate solution is available. It has become mainstream.

  By the way, in recent years, the contact area between the patterned photosensitive layer and the substrate has been reduced with the increase in the density and resolution of the printed wiring board, so in the development, etching or plating process step, The resist material is required to have mechanical strength, chemical resistance, flexibility, and the like, as well as adhesion between the photosensitive layer and the base material and resolution of the photosensitive layer.

  In order to improve the resolution of the photosensitive layer, it is effective to reduce the thickness of the photosensitive layer. However, when a certain level of circuit thickness (copper thickness, etc.) is required during the production of printed wiring boards, the etching method has the effect of side etching during etching, so that the resist lines at the thin line portions are likely to be lost. It has been difficult to achieve a high resolution of a printed wiring board while achieving both a good circuit thickness and a narrow circuit width. Further, in the plating method, when the photosensitive layer is thinned, it is difficult to obtain a required circuit thickness, and thus there is a limit to increasing the resolution of the printed wiring board.

  In addition, attempts have been made to achieve high resolution of printed wiring boards by methods other than thinning the photosensitive layer. The resin film is peeled off before exposure, and a photo tool is directly applied on the photosensitive resin composition. A method of making it adhere is known. However, the photosensitive layer usually retains a certain degree of adhesion so as to be in close contact with the substrate. When this method is applied, the phototool and the photosensitive layer are in close contact with each other, making it difficult to remove the phototool and improving workability. There are problems such as reduction, contamination of the phototool by the photosensitive resin composition, and reduction in sensitivity due to the influence of oxygen inhibition.

  Therefore, as an attempt to improve this method, a method in which two or more photosensitive layers are used and a layer that is in direct contact with the phototool is a non-adhesive resin layer is used (see, for example, Patent Documents 1 to 3). However, this method requires time and effort for coating to make the photosensitive layer multi-layered, and it cannot be said that it is sufficiently effective for lowering the sensitivity, and the printed wiring board has a higher density and higher resolution. It was difficult to achieve.

  Furthermore, as a method for achieving higher density and higher resolution of a printed wiring board, a method of manufacturing a printed wiring board by a semi-additive method has attracted attention. This method prints by sequentially forming an ultra-thin conductor layer by electroless plating on the substrate, resist pattern formation, plating, resist stripping and quick etching (unnecessary ultra-thin conductor layer removal). This is a method of forming a wiring board. According to this method, the influence of side etching can be reduced, and a good circuit can be obtained. However, when the conventional photosensitive element is used in the semi-additive method, the problem that the side surface of the resist pattern becomes rough occurs, and it is difficult to obtain a plating circuit having a good side surface shape. There is a limit to increasing the density and resolution of the.

JP 61-31855 A JP-A-1-221735 JP-A-2-230149

  In addition to the problems described above, the present inventors have attempted to form a resist pattern on a substrate using a conventional photosensitive element. There are problems such as the so-called skirting that causes the width of the bonding part with the material to increase, and the side surface of the resist pattern becoming rough. These problems are due to the high density and high resolution of printed wiring boards. It was found that this is an obstacle to achieving sufficient conversion.

  The present invention has been made in view of the above circumstances, and can form a resist pattern having excellent resolution, reducing the amount of skirting of the resist pattern, and having a favorable shape on the side surface of the resist pattern. The object is to provide a possible photosensitive element. Furthermore, it aims at providing the formation method of a resist pattern using this photosensitive element, and the manufacturing method of a printed wiring board.

  In order to achieve the above object, the present invention provides a photosensitive resin composition comprising (A) a binder polymer, (B) a photopolymerizable compound having an ethylenically unsaturated bond, and (C) a photopolymerization initiator. A photosensitive element comprising a photosensitive layer comprising a resin layer, wherein the acid value of the component (A) is 50 to 120 mgKOH / g, and the haze of the resin film is 1% or less. A photosensitive element is provided.

  According to such a photosensitive element, it is possible to form a resist pattern having an excellent resolution, a sufficient amount of skirting, and a good side shape. As a result, it is possible to sufficiently achieve higher density and higher resolution of the printed wiring board that could not be achieved conventionally. Such an effect is that the photosensitive layer is formed by the photosensitive resin composition containing the component (A) having an acid value in a specific range of 50 to 120 mgKOH / g, and the haze of the resin film is 1% or less. It is considered that this is what is played.

  Here, when either of the acid value of the component (A) or the haze of the resin film does not satisfy the above condition, the amount of skirting is reduced and the formation of a resist pattern having a favorable side surface shape Both cannot be achieved at the same time, and it is difficult to achieve high density and high resolution of the printed wiring board. By satisfying the above conditions for both the acid value and haze, it is possible to simultaneously achieve both reduction in the amount of tailing and formation of a resist pattern with a favorable side shape, and excellent resolution and fine lines. Plating peelability can be obtained.

  The present invention also includes a lamination step of laminating the photosensitive element on the circuit forming substrate in the order of the photosensitive layer and the resin film, and irradiating a predetermined portion of the photosensitive layer with active light through the resin film. A resist pattern forming method comprising: an exposure step of forming a photocured portion on the photosensitive layer; and a developing step of removing the photosensitive layer other than the photocured portion, and the resist pattern There is provided 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 forming method.

  Since the resist pattern forming method and the printed wiring board manufacturing method of the present invention use the photosensitive element of the present invention, it is possible to form a resist pattern with reduced skirting and good side shape. Accordingly, it is possible to increase the density and resolution of the printed wiring board.

  As described above, according to the present invention, it is possible to provide a photosensitive element that is capable of forming a resist pattern that is excellent in resolution, has a sufficiently reduced tailing amount, and has a favorable side shape. It becomes possible. In addition, according to the present invention, it is possible to provide a method for forming a resist pattern using such a photosensitive element, thereby producing a printed wiring board capable of increasing the density and resolution of the printed wiring board. It is possible to provide a method.

  Hereinafter, the present invention will be described in detail with reference to preferred embodiments thereof. The (meth) acrylic acid in the present invention means acrylic acid or methacrylic acid, and the same applies to (meth) acrylate and (meth) acryloyl.

(Photosensitive element)
FIG. 1 is a schematic cross-sectional view showing a preferred embodiment of the photosensitive element of the present invention. The photosensitive element 1 shown in FIG. 1 has a structure in which a photosensitive layer 14 is laminated on a resin film 10. The photosensitive layer 14 is a layer comprising a photosensitive resin composition containing (A) a binder polymer, (B) a photopolymerizable compound having an ethylenically unsaturated bond, and (C) a photopolymerization initiator, and The acid value of the component (A) is 50 to 120 mgKOH / g. The haze of the resin film is 1% or less.

  First, the resin film 10 concerning the photosensitive element 1 of this invention is demonstrated.

  The resin film 10 is not particularly limited as long as the haze is 1% or less, and examples thereof include films made of heat-resistant and solvent-resistant polymers such as polyethylene terephthalate, polypropylene, polyethylene, and polyester. A polyethylene terephthalate film is preferred. The resin film 10 may have a single layer structure or a multilayer structure in which films having a plurality of compositions are laminated.

  Here, the haze of the resin film 10 needs to be 1% or less, preferably 0.5% or less, and more preferably 0.3% or less. When the haze exceeds 1%, the effects of the present invention as described above cannot be obtained sufficiently, and the side shape of the resist pattern is deteriorated and the resolution is lowered. When the side surface shape of the resist pattern deteriorates, the side surface shape of the plating line also deteriorates during plating when manufacturing a printed wiring board, and the electrical characteristics deteriorate. In addition, it becomes difficult to accurately etch the base with a desired line width during etching when manufacturing a printed wiring board. Haze can be measured in accordance with JIS K 7105. For example, it can be measured with a commercially available turbidimeter such as NDH-1001DP (trade name, manufactured by Nippon Denshoku Industries Co., Ltd.). .

  The thickness of the resin film 10 is preferably 5 to 20 μm, more preferably 8 to 18 μm, and particularly preferably 10 to 16 μm. When the thickness is less than 5 μm, the resin film 10 tends to be broken when the resin film 10 is peeled before development. When the thickness exceeds 20 μm, the resolution is lowered or the side shape of the resist pattern is deteriorated. There is also a tendency to be less expensive.

  Next, the photosensitive layer 14 according to the photosensitive element 1 of the present invention will be described.

As described above, the photosensitive layer 14 includes the following components (A) to (C):
(A) Binder polymer (B) Photopolymerizable compound having an ethylenically unsaturated bond (C) A photosensitive resin composition containing a photopolymerization initiator, wherein the acid value of component (A) is 50 It is -120 mgKOH / g.

  (A) The acid value of the binder polymer needs to be 50 to 120 mgKOH / g, preferably 80 to 110 mgKOH / g, and more preferably 100 to 110 mgKOH / g. When the acid value is less than 50 mgKOH / g, the development time tends to be long, and the peelability of the resist pattern after etching or plating deteriorates. On the other hand, when the acid value exceeds 120 mgKOH / g, the trailing amount of the resist pattern after development increases, and the developer resistance of the photocured resist pattern decreases.

  Here, the acid value of the (A) binder polymer can be measured by the following procedure. That is, (A) a binder polymer is dissolved in toluene / methyl alcohol (volume ratio: 7/3), an indicator (phenolphthalein / methanol (mass ratio: 1/100)) is added, and 0.1N potassium hydroxide is added. Titrate with alcohol solution. The time when the color changes from colorless to slightly red is measured as the end point. In the calculation of the acid value, the above mixed solvent alone is titrated in the same manner, and the titration value is subtracted as a blank. Moreover, an acid value means the average value (acid value as a whole), when (A) binder polymer consists of two or more components.

  Conventionally, the acid value of the component (A) has been set to a preferred upper limit mainly from the viewpoint of the resist resistance of the resist pattern, but the acid value of the component (A) is added to the bottom of the resist pattern after development. The present inventors have found that the value is greatly affected. Further, by setting the acid value to 120 mgKOH / g or less, it becomes possible to greatly reduce the skirting amount of the resist pattern.

  In addition, the photosensitive element 1 of the present invention satisfies the effects of the present invention more sufficiently by satisfying the respective preferred ranges of the haze of the resin film 10 and the acid value of the component (A) described above in combination. It becomes possible to express. That is, for example, the case where the haze of the resin film is 0.3% or less and the acid value of the component (A) is 100 to 110 mg KOH / g is most preferable. In this case, the photosensitive element of the present invention is In particular, an excellent resolution can be obtained, the resist pattern side surface shape can be made extremely good, and an effect that the skirting amount of the resist pattern can be greatly reduced is obtained. Higher density and higher resolution can be realized more reliably.

  Examples of the binder polymer used as the component (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. In addition, these can be used individually or in combination of 2 or more types.

  (A) The binder polymer can be produced, for example, by radical polymerization of a monomer (polymerizable monomer). Examples of the monomer include styrene; polymerizable styrene derivatives such as vinyl toluene, α-methyl styrene, p-methyl styrene, and p-ethyl styrene; acrylamides; acrylonitrile; esters of vinyl alcohol such as vinyl-n-butyl ether. (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 (meth) Substituted (meth) acrylic acid such as crylic acid, β-styryl (meth) acrylic acid; maleic acid; maleic anhydride; maleic monoester such as monomethyl maleate, monoethyl maleate, monoisopropyl maleate; fumaric acid, Cinnamic acid, α-cyanocinnamic acid, itaconic acid, crotonic acid, propiolic acid and the like can be mentioned. 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) Examples include 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.

  (A) From the standpoint of alkali developability, the (A) binder polymer preferably has a carboxyl group, and can be produced, for example, by polymerizing a monomer mixture containing a monomer having a carboxyl group. As the monomer having a carboxyl group, (meth) acrylic acid is preferable.

  Moreover, it is preferable that (A) binder polymer contains the binder polymer obtained by polymerizing the monomer mixture containing methacrylic acid, in order to obtain more excellent alkali developability.

  Moreover, it is preferable that (A) binder polymer contains the binder polymer obtained by polymerizing the monomer mixture containing a styrene-type monomer from the viewpoint of adhesiveness and chemical resistance (plating resistance). Here, the styrene monomer includes styrene and a styrene derivative (examples of the styrene derivative are as described above).

  Further, the (A) binder polymer preferably contains a binder polymer obtained by polymerizing a monomer mixture containing a (meth) acrylic acid alkyl ester having 4 to 10 carbon atoms in the alkyl group. By including such a binder polymer, the skirting amount of the resist pattern can be reduced more sufficiently, the side shape of the resist pattern can be made better, and excellent resolution can be obtained. Can do.

  Furthermore, (A) the binder polymer is preferably all made of a copolymer of styrene monomer, (meth) acrylic acid and (meth) acrylic acid alkyl ester, whereby the photosensitive element of the present invention is more There is a tendency that excellent resolution can be obtained, the side surface shape of the resist pattern can be made extremely good, and the skirting amount of the resist pattern can be more sufficiently reduced.

  The content of the styrenic monomer is preferably 3 to 30% by weight, more preferably 4 to 28% by weight, and particularly preferably 5 to 27% by weight based on the total weight of the monomers. preferable. When this content is less than 3% by weight, the adhesion tends to be inferior, and when it exceeds 30% by weight, the release piece tends to be large and the release time tends to be long.

  (A) The weight average molecular weight of the binder polymer is preferably 30000 to 60000, more preferably 30000 to 50000, and particularly preferably 40000 to 50000. If the weight average molecular weight is less than 30,000, the photosensitive layer 14 tends to be brittle, and if it exceeds 60,000, a thread-like development residue due to insufficient resolution tends to occur. In addition, the weight average molecular weight is measured by gel permeation chromatography (GPC), and a value converted to standard polystyrene is used. In addition, when the (A) binder polymer is composed of a plurality of components, the brittleness of the photosensitive layer 14 and the residual thread-like development can be reduced when at least one of the binder polymers is within the range of the above weight average molecular weight. it can. From the viewpoint of obtaining such an effect more sufficiently, it is preferable that the binder polymer having the largest blending amount among the plurality of binder polymers is within the range of the weight average molecular weight. Further, from the viewpoint of obtaining such an effect more sufficiently, the average value of the weight average molecular weights of the plurality of binder polymers (the weight average molecular weight as a whole) is preferably within the above range of the weight average molecular weight. Furthermore, from the viewpoint of obtaining such effects more fully, it is most preferable that the weight average molecular weight of all the binder polymers is within the above-mentioned range of the weight average molecular weight.

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

  These (A) 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 made of different monomers, 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. Etc. In addition, a binder polymer having a multimode molecular weight distribution described in JP-A-11-327137 can also be used.

  (B) As a photopolymerizable compound which has an ethylenically unsaturated bond, it is preferable to contain the compound which has 4-40 C2-C6 oxyalkylene units in a molecule | numerator. By containing such a compound as the component (B), the compatibility with the binder polymer (A) can be improved, and the effects of the present invention as described above tend to be obtained with certainty.

  Here, examples of the oxyalkylene unit having 2 to 6 carbon atoms include an oxyethylene unit, an oxypropylene unit, an oxyisopropylene unit, an oxybutylene unit, an oxypentylene unit, and an oxyhexylene unit. From the viewpoint of plating properties, oxyethylene units or oxyisopropylene units are preferred.

  Among these photopolymerizable compounds, bisphenol A (meth) acrylate compounds or polyalkylene glycol di (meth) acrylates are particularly preferably used because the effects of the present invention tend to be obtained more reliably. it can.

Preferred examples of the bisphenol A (meth) acrylate compound include compounds represented by the following general formula (I).

In the general formula (I), R ¹ and R ² each independently represent a hydrogen atom or a methyl group, and is preferably a methyl group. In the general formula (I), X ¹ and X ² 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 (I), p and q are positive integers selected such that p + q = 4 to 40, and the value of p + q is preferably 6 to 34, more preferably 8 to 30. It is particularly preferably 8 to 28, very preferably 8 to 20, very preferably 8 to 16, and most preferably 8 to 12. When the value of 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. However, the resist image tends to be peeled off during development, and the plating resistance against solder plating tends to be lowered. In either case, the resolution of the photosensitive element tends to decrease, and it tends to be difficult to achieve high density and high resolution of the printed wiring board.

  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, and a hexylene group. From the viewpoint of resolution and plating resistance, an ethylene group and an isopropylene group. Is preferred.

  In addition, the aromatic ring in the general formula (I) may have a substituent. 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, or an aryl group substituted by these substituents. The above substituents may form a condensed ring, and a hydrogen atom in these substituents may be substituted with the above substituent 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 (I) 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 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane include 2,2-bis (4-((meth) acryloxydiethoxy) phenyl) propane, 2,2- Bis (4-((meth) acryloxytriethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxytetraethoxy) phenyl) propane, 2,2-bis (4-((meth)) Acryloxypentaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyhexaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyheptaethoxy) phenyl) propane 2,2-bis (4-((meth) acryloxyoctaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxy nonaethoxy) ) Phenyl) propane, 2,2-bis (4-((meth) acryloxydecaethoxy) phenyl), 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) acrylic) Loxytetradecaethoxy) phenyl), 2,2-bis (4-((meth) acryloxypentadecaethoxy) phenyl), 2,2-bis (4-((meth) acryloxyhexadecaethoxy) phenyl), etc. 2,2-bis (4- (methacryloxypentaethoxy) phenyl) propane is commercially available as BPE-500 (product name, manufactured by Shin-Nakamura Chemical Co., Ltd.) , And the 2,2-bis (4- (methacryloxy pentadecanoyl) phenyl) is, BPE-1300 is commercially available as (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.). These can be used alone or in combination of two or more.

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

Preferred examples of the polyalkylene glycol di (meth) acrylate include compounds represented by the following general formula (II).

In the general formula (II), 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 ^{(II), Y 1, Y} 2 and ^{Y 3} is an alkylene group having 2 to 6 carbon atoms is preferably an ethylene group or a propylene group. In the general formula (II), s, t, and u represent an integer of 0-30 selected so that s + t + u = 4-40, and the value of s + t + u is preferably 5-30, and 8-23 More preferably, it is particularly preferably 10-15. When the value of s + t + u is less than 4, the boiling point of the compound tends to decrease and the odor of the photosensitive layer 14 tends to increase. When the value exceeds 40, the concentration of the photoreactive site per unit weight is lowered. There is a tendency that high sensitivity cannot be obtained.

Moreover, the oxyalkylene unit (— (Y ¹ —O) _s —, — (Y ² —O) _t —, and — (Y ³ —O) _u —) in the general formula (II) is, for example, When including a plurality of oxyethylene units and oxypropylene units, the plurality of oxyethylene units and oxypropylene units do not need to be continuously present in blocks, and may be present randomly. .

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

  Preferable examples of the compound represented by the general formula (II) include compounds represented by the following general formulas (III) to (V). 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はオキシエチレン単位を示し、ＰＯはオキシプロピレン単位を示し、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 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, EO represents an oxyethylene unit, PO represents an oxypropylene unit, 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は水素原子又は炭素数１〜３のアルキル基を示し、ＥＯはオキシエチレン単位を示し、ＰＯはオキシプロピレン単位を示し、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 represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, EO represents an oxyethylene unit, PO represents an oxypropylene unit, and m ³ , n ² and n ³ represent m ³ + ⁿ indicates the 30 integer selected to 2 ⁺ n 3 = 4~40 become so. ]

［式中、Ｒ^３及びＲ^４は水素原子又は炭素数１〜３のアルキル基を示し、ＥＯはオキシエチレン単位を示し、ＰＯはオキシプロピレン単位を示し、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 represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, EO represents an oxyethylene unit, PO represents an oxypropylene unit, and m ⁴ and n ⁴ represent m ⁴ + n ^4. = An integer of 1 to 30 selected to be 4 to 40. ]

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

The total number of repeating oxyethylene units (m ¹ + m ² , m ³ and m ⁴ ) in the general formulas (III) to (V) is preferably an integer of 1 to 30, and an integer of 1 to 10 It is more preferable that it is an integer of 4-9, and it is most 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 oxypropylene units (n ¹ , n ² + n ³ and n ⁴ ) in the above general formulas (III) to (V) 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 most 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 (III) include, for example, vinyl in which R ³ and R ⁴ are a methyl group, 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 (IV) 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 (V) 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. In addition, these can be used individually or in combination of 2 or more types.

  As the component (B), in addition to the photopolymerizable compound having an ethylenically unsaturated bond as described above, it is preferable to further contain another photopolymerizable compound having an ethylenically unsaturated bond, for example, Nonylphenoxypolyethyleneoxy (meth) acrylate, nonylphenoxypolypropyleneoxy (meth) acrylate, nonylphenoxypolyethyleneoxypolypropyleneoxy (meth) acrylate, and other nonylphenoxypolyalkyleneoxy (meth) acrylates, γ-chloro-β-hydroxypropyl- Examples include phthalic acid compounds such as β ′-(meth) acryloyloxyethyl-o-phthalate and β-hydroxyalkyl-β ′-(meth) acryloyloxyalkyl-o-phthalate, and (meth) acrylic acid alkyl esters. .

  In addition, the photosensitive resin composition of the present invention can contain a photopolymerizable compound other than the above-described photopolymerizable compound. For example, a glycidyl group-containing compound is reacted with an α, β-unsaturated carboxylic acid. And a urethane monomer such as a (meth) acrylate compound having a urethane bond in the molecule.

  (C) As the photopolymerization initiator, for example, N, N′-tetraalkyl-4,4′-diaminobenzophenone such as benzophenone, N, N′-tetramethyl-4,4′-diaminobenzophenone (Michler ketone), Aromatic ketones such as 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propanone-1; Quinones such as alkylanthraquinone, 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 (meth) Ciphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p- Acridine such as 2,4,5-triarylimidazole dimer such as methoxyphenyl) -4,5-diphenylimidazole dimer, 9-phenylacridine, 1,7-bis (9,9′-acridinyl) heptane Derivatives, N-phenylglycine, N-phenylglycine derivatives, coumarin compounds and the like can be mentioned. 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 can be used alone or in combination of two or more.

  The blending amount of the (A) binder polymer is preferably 40 to 70 parts by weight, more preferably 50 to 60 parts by weight, with the total amount of the (A) component and the (B) component being 100 parts by weight. If the amount is less than 40 parts by weight, the photocured product tends to be brittle, and if it exceeds 70 parts by weight, the resolution and photosensitivity tend to be insufficient.

  (B) The compounding quantity of the photopolymerizable compound which has an ethylenically unsaturated bond is preferable that it is 30-60 weight part by making the total amount of (A) component and (B) component into 100 weight part, 40-50 More preferred are parts by weight. If the amount is less than 30 parts by weight, the resolution and photosensitivity tend to be insufficient, and if it exceeds 60 parts by weight, the photocured product tends to be brittle.

  (C) It is preferable that the compounding quantity of a photoinitiator is 0.1-20 weight part with respect to 100 weight part of total amounts of (A) component and (B) component, 0.2-10 weight part It is more preferable that If the blending amount is less than 0.1 parts by weight, the photosensitivity tends to be insufficient, and if it exceeds 20 parts by weight, the absorption on the surface of the photosensitive resin composition increases during exposure, and the internal Photocuring tends to be inadequate.

  In addition, the photosensitive resin composition may include a photopolymerizable compound (oxetane compound or the like) having at least one cationically polymerizable cyclic ether group in the molecule, a cationic polymerization initiator, a dye such as malachite green, if necessary. , Photochromic agents such as tribromophenylsulfone and leucocrystal violet, thermochromic inhibitors, plasticizers such as p-toluenesulfonamide, pigments, fillers, antifoaming agents, flame retardants, stabilizers, adhesion-imparting agents, A leveling agent, a peeling accelerator, an antioxidant, a fragrance, an imaging agent, a thermal crosslinking agent, and the like are included in an amount of about 0.01 to 20 parts by weight with respect to 100 parts by weight of the total amount of the component (A) and the component (B). be able to. These can be used alone or in combination of two or more.

  Furthermore, the photosensitive resin composition may be mixed with a solvent such as methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N-dimethylformamide, propylene glycol monomethyl ether, or a mixed solvent thereof as necessary. It melt | dissolves and it can apply | coat as a solution of about 30-60 weight% of solid content.

  The photosensitive layer 14 concerning the photosensitive element 1 of this invention can be formed by apply | coating the above-mentioned photosensitive resin composition on the resin film 10, and removing a solvent. Here, as a coating method, for example, 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 can be employed. Moreover, the removal of a solvent can be performed by processing for about 5 to 30 minutes at the temperature of 70-150 degreeC, for example. The amount of the remaining organic solvent in the photosensitive layer is preferably 2% by weight or less from the viewpoint of preventing the organic solvent from diffusing in the subsequent step.

  The thickness of the photosensitive layer 14 thus formed is more preferably 5 to 35 μm, particularly preferably 15 to 30 μm, and most preferably 20 to 25 μm after drying. . If this thickness is less than 5 μm, problems tend to occur when the photosensitive layer is laminated on the circuit forming substrate, and the production yield of the printed wiring board tends to decrease. On the other hand, if the thickness exceeds 35 μm, the resolution of the photosensitive layer 14 deteriorates, and it tends to be difficult to produce a high-density printed wiring board.

  The photosensitive element 1 of the present invention can be obtained by laminating the photosensitive layer 14 on the resin film 10 as described above. Moreover, the photosensitive element 1 of this invention may have the structure by which the protective film was further laminated | stacked on the surface F1 on the opposite side to the surface which contact | connects the resin film 10 of the photosensitive layer 14. FIG.

  As this protective film, it is preferable to use a film having a lower adhesive force between the photosensitive layer 14 and the protective film than an adhesive force between the photosensitive layer 14 and the resin film 10. It is preferable to use an eye film. Specific examples include inert polyolefin films such as polyethylene and polypropylene, and polyethylene films are preferred from the viewpoint of peelability from the photosensitive layer 14.

  Moreover, the photosensitive element 1 of this invention may have intermediate | middle layers and protective layers, such as a cushion layer, an adhesive layer, a light absorption layer, and a gas barrier layer other than the photosensitive layer 14, the resin film 10, and a protective film. Good.

  The photosensitive element 1 of the present invention can be stored, for example, as it is or in a state where a protective film is laminated on a cylindrical core. At this time, it is preferable that the resin film 10 is wound in a roll shape so as to be on the outside. Moreover, it is preferable to install an end face separator on the end face of the photosensitive element 1 wound up in a roll shape from the viewpoint of end face protection, and it is preferable to install a moisture-proof end face separator from the viewpoint of edge fusion resistance. Moreover, as a packaging method, it is preferable to wrap and package in a black sheet with low moisture permeability.

  Examples of the core material include plastics such as polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, ABS resin (acrylonitrile-butadiene-styrene copolymer).

(Method for forming resist pattern)
The resist pattern forming method of the present invention includes a laminating step of laminating the photosensitive element 1 of the present invention on a circuit forming substrate in the order of the photosensitive layer 14 and the resin film 10, and actinic rays through the resin film 10. The method includes an exposure step of irradiating a predetermined portion of the photosensitive layer 14 to form a photocured portion on the photosensitive layer 14 and a developing step of removing the photosensitive layer 14 other than the photocured portion.

  In the laminating step, as a method of laminating the photosensitive layer 14 on the circuit forming substrate, when a protective film is present on the photosensitive layer 14, the protective layer 14 is removed after the protective film is removed. Examples of the method include laminating by heating to about 130 ° C. with a pressure of about 0.1 to 1 MPa on the circuit forming substrate, and the laminating can be performed under reduced pressure. The surface on which the circuit forming substrate is laminated is usually a metal surface, but is not particularly limited. Further, in order to further improve the stackability, a pre-heat treatment of the circuit forming substrate may be performed.

  Next, the exposure step irradiates the photosensitive layer 14 with an actinic ray in an image form through the negative or positive mask pattern and the resin film 10 and completes the photocuring portion on the photosensitive layer 14. This is done by forming. As the light source of the actinic light, a known light source such as a carbon arc lamp, a mercury vapor arc lamp, a high pressure mercury lamp, a xenon lamp, or the like that effectively emits ultraviolet rays or visible light is used. It is also used for laser direct drawing exposure.

  Next, in the development step, after the exposure step, the resin film 10 is removed, and the unexposed portion (photocured portion) is removed by wet development, dry development, or the like using a developer such as an alkaline aqueous solution, an aqueous developer, or an organic solvent. Then, it can be developed to produce a resist pattern.

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

Moreover, as a process after a development process, you may further harden a resist pattern by performing about 60-250 degreeC heating or about 0.2-10 J / cm < ² > exposure as needed.

(Printed wiring board manufacturing method)
The printed wiring board manufacturing method of the present invention is performed by etching or plating a circuit forming substrate on which a resist pattern is formed by the resist pattern forming method of the present invention. Here, etching or plating of the circuit forming substrate is performed by etching or plating the surface of the circuit forming substrate by a known method using the developed resist pattern as a mask.

  As an etching solution used for etching, for example, a cupric chloride solution, a ferric chloride solution, an alkaline etching solution, or the like can be used.

  Examples of plating include copper plating, solder plating, nickel plating, and 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 weight sodium hydroxide aqueous solution, a 1 to 10% by weight potassium hydroxide aqueous solution and the like are used. Moreover, as a peeling system, an immersion system, a spray system, etc. are mentioned, for example. 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.

  In addition, when 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.

(Production of component (A))
A polymer obtained by copolymerizing the monomers shown in Table 1 at a weight ratio shown in the same table was dissolved in toluene / methylcellosolve (weight ratio: 4/6) so that the solid content was 40% by weight. (A) Components 1 to 6 were obtained. The weight average molecular weight and acid value of the polymer are as shown in Table 1.

(Preparation of photosensitive composition solution)
Next, the materials shown in Table 2 were blended to obtain a photosensitive resin composition solution.

(Production of photosensitive element)
The obtained photosensitive resin composition solution was uniformly applied to a 16 μm-thick polyethylene terephthalate film (PET film) shown in Table 3, and the solvent was removed by drying with a hot air convection dryer at 100 ° C. for 10 minutes. Thereafter, a polyethylene protective film (manufactured by Tamapoly Co., Ltd., trade name: NF-15, tensile strength in the film longitudinal direction: 16 MPa, tensile strength in the film width direction: 12 MPa) was used to cover Examples 1 to 3 and The photosensitive elements of Comparative Examples 1 to 5 were obtained. The thickness of the photosensitive layer after drying was 25 μm.

(Production of laminate)
The copper surface of a copper-clad laminate (made by Hitachi Chemical Co., Ltd., product name: MCL-E-61), which is a glass epoxy material laminated with copper foil (thickness: 35 μm) on both sides, is a brush equivalent to # 600. Polishing was performed using a polishing machine (manufactured by Sankei Co., Ltd.), washed with water, and then dried with an air flow. By heating the obtained copper-clad laminate to 80 ° C. and laminating the photosensitive element on the copper surface at a speed of 3 m / min using a 120 ° C. heat roll while peeling off the protective film, Laminated bodies obtained by laminating the photosensitive elements of Examples 1 to 3 and Comparative Examples 1 to 5 on a copper-clad laminate were obtained. These laminates are used as test pieces in the evaluation tests of the characteristics of the photosensitive elements shown below. In addition, unless otherwise indicated, such a test piece uses a separate test piece for each test.

(Minimum development time measurement test)
The PET film was peeled from the test piece, and the minimum time (minimum development time, unit: second) in which the unexposed portion of the photosensitive layer could be completely removed was evaluated using a 1 wt% sodium carbonate aqueous solution at 30 ° C. The results are shown in Table 3. In the test piece of Comparative Example 4, the photosensitive layer could not be completely removed even after 30 seconds of development.

(Light sensitivity test)
On the PET film of the test piece, a stove 21-step tablet was placed as a negative, and an energy of 60 mJ / cm ² using an exposure machine having a high pressure mercury lamp lamp (trade name: EXM-1201, manufactured by Oak Co., Ltd.). The exposure was performed so as to obtain an amount. Subsequently, the PET film is peeled off, and a 1% by weight aqueous sodium carbonate solution at 30 ° C. is sprayed onto the photosensitive layer for twice the minimum development time measured in the above minimum development time measurement test to remove unexposed portions. And developed. And the photosensitivity of the photosensitive resin composition was evaluated by measuring the step number of the step tablet of the photocured film formed on the copper clad laminated board. The results are shown in Table 3. The light sensitivity is indicated by the number of steps of the step tablet, and the higher the number of steps of the step tablet, the higher the light sensitivity. In the test piece of Comparative Example 4, the unexposed portion could not be sufficiently removed during development, and the photosensitivity could not be evaluated.

(Resolution test)
In order to investigate the resolution, a photo tool having a stove 21-step tablet and a photo tool having a wiring pattern having a line width / space width of 10/10 to 50/50 (unit: μm) as a negative for resolution evaluation were tested. Using an exposure machine having a high-pressure mercury lamp lamp in close contact with a piece of PET film, exposure was performed with an energy amount such that the number of remaining step stages after development of the stove 21-step step tablet was 7.0. Subsequently, the PET film is peeled off, and a 1% by weight aqueous sodium carbonate solution at 30 ° C. is sprayed onto the photosensitive layer for twice the minimum development time measured in the above minimum development time measurement test to remove unexposed portions. And developed. Here, the resolution was evaluated based on the smallest value (unit: μm) of the space width between the line widths in which the unexposed portion could be removed cleanly by the development process. The results are shown in Table 3. Note that the smaller the numerical value, the better the evaluation of resolution. In the test piece of Comparative Example 4, the unexposed portion could not be sufficiently removed during development, and a resist pattern capable of evaluating the resolution could not be formed.

(Adhesion test)
In order to investigate the adhesion, a photo tool having a stove 21-step tablet and a photo tool having a wiring pattern having a line width / space width of 10/400 to 47/400 (unit: μm) as a negative for resolution evaluation The test piece was placed in close contact with the PET film and exposed using an exposure machine having a high-pressure mercury lamp lamp with an energy amount such that the number of remaining steps after development of the stove 21-step tablet was 7.0. Subsequently, the PET film is peeled off, and a 1% by weight aqueous sodium carbonate solution at 30 ° C. is sprayed onto the photosensitive layer for twice the minimum development time measured in the above minimum development time measurement test to remove unexposed portions. And developed. Here, the adhesiveness is such that the resist that forms the post-development line is in close contact with the substrate and is not peeled off, and the line width is such that the line does not meander or bend. Evaluation was based on the smallest value (unit: μm). The results are shown in Table 3. In addition, evaluation of adhesiveness is a favorable value, so that a numerical value is small. In the test piece of Comparative Example 4, the unexposed portion could not be sufficiently removed during development, and a resist pattern capable of evaluating adhesion could not be formed.

(Thin wire plating peelability test)
For fine wire plating peelability, a laminate (excluding Comparative Example 4) after development in the resolution test was used as a test piece. This test piece was immersed in a degreasing bath (Meltex Co., Ltd., PC-455 (25% by weight)) for 5 minutes and washed with water. Subsequently, it was immersed in a soft etching bath (ammonium persulfate 150 g / liter) for 2 minutes and washed with water. Further, pretreatment was performed in the order of 1 minute immersion in a 10 wt% sulfuric acid bath, and a copper sulfate plating bath (copper sulfate pentahydrate 60 g / liter, sulfuric acid 98 ml / liter, sodium chloride 100 mg / liter, basic leveler capaside (Atotech Japan Co., Ltd.) 20 ml / liter, Brightening agent Kaparaside Universal (Atotech Japan Co., Ltd. 3 ml / liter) was put in, and copper sulfate plating was performed at room temperature at 2 A / dm ² for 35 minutes. . Next, a 3% by weight sodium hydroxide aqueous solution was sprayed for 2 minutes, and the fine wire plating peelability was evaluated based on the smallest value of the space width between the plating line widths where the resist was completely removed. The results are shown in Table 3. In addition, evaluation of fine wire plating peelability is so favorable that a numerical value is small.

(Resist pattern side surface shape evaluation)
In addition, the side surface shape of the copper plating line in the fine wire plating peelability test (excluding Comparative Example 4) was observed with a scanning electron microscope (SEM), and in three stages of ◯, Δ, and × according to the following evaluation criteria. evaluated. The results are shown in Table 3. In addition, that the side surface shape of this copper plating line is good means that the side surface shape of the resist pattern is good.
○: Smooth side surface shape.
X: It is a rough side surface shape.
Δ: A side surface shape with a smoothness intermediate between ○ and ×.

(Filling amount measurement test)
In the production of the above laminate, instead of a copper-clad laminate that is a glass epoxy material laminated with copper foil on both sides, a polyimide substrate on which copper is deposited is acid-washed with a 1% by volume hydrochloric acid aqueous solution and then washed with water The photosensitive elements of Examples 1 to 3 and Comparative Examples 1 to 5 were formed on the polyimide substrate in the same procedure as that for the production of the laminate except that a polyimide substrate obtained by drying with an air flow was used. Each laminated body obtained by laminating was obtained. Using this laminate, exposure and development were performed in the same procedure as in the resolution test to form a resist pattern. About the formed resist pattern, the cross-sectional shape of the resist pattern was observed with a focused ion beam processing apparatus (FIB) and a scanning electron microscope (SEM), and the skirting amount (unit: μm) of the resist pattern was obtained. Here, in order to explain the skirting amount of the resist pattern, reference is made to FIG. 2 which is a cross-sectional view of a plane orthogonal to the length direction of the resist pattern formed on the substrate. As shown in FIG. 2, the skirting amount of the resist pattern 22 is an intersection line between the surface along the planar side surface 231 where the skirting is not generated and the surface of the substrate 21 among the side surfaces 23 of the resist pattern 22. When the intersection line between the side surface 23 of the resist pattern 22 and the surface of the substrate 21 is L2, it is represented by a distance W between L1 and L2. In addition, when there is a difference in the skirting amount on both side surfaces of the resist pattern, it means an average value thereof. The results are shown in Table 3. In addition, the skirting amount is a better value as the numerical value is smaller. Moreover, in the test piece of Comparative Example 4, the unexposed portion could not be sufficiently removed during development, and a resist pattern capable of evaluating the skirting amount could not be formed.

  As is clear from the results shown in Table 3, according to Examples 1 to 3 using the photosensitive element of the present invention, compared with Comparative Examples 1 to 5, the resolution, fine wire plating peelability, and copper plating It was confirmed that the shape of the line side surface is good and the skirting amount of the resist pattern can be greatly reduced.

It is a schematic cross section which shows suitable one Embodiment of the photosensitive element of this invention. It is a schematic cross section for demonstrating the skirting amount of a resist pattern.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Photosensitive element, 10 ... Resin film, 14 ... Photosensitive layer, 21 ... Board | substrate, 22 ... Resist pattern.

Claims (14)

Photosensitive provided on a resin film with a photosensitive layer comprising (A) a binder polymer, (B) a photopolymerizable compound having an ethylenically unsaturated bond, and (C) a photopolymerization initiator. A sex element,
The acid value of the component (A) is 50 to 120 mgKOH / g,
A photosensitive element, wherein the resin film has a haze of 1% or less.   The photosensitive element according to claim 1, wherein the photosensitive layer has a thickness of 5 to 35 μm.   The photosensitive element according to claim 1, wherein the resin film has a thickness of 5 to 20 μm.   The component (A) includes a binder polymer obtained by polymerizing a monomer mixture containing styrene and / or a styrene derivative, according to any one of claims 1 to 3. The photosensitive element as described.   The said (A) component contains the binder polymer obtained by superposing | polymerizing the monomer mixture containing methacrylic acid, The photosensitive property as described in any one of Claims 1-4 characterized by the above-mentioned. element.   The component (A) includes a binder polymer obtained by polymerizing a monomer mixture containing a (meth) acrylic acid alkyl ester having 4 to 10 carbon atoms in an alkyl group. The photosensitive element as described in any one of 1-5.   The photosensitive element according to claim 1, wherein the component (A) has a weight average molecular weight of 30,000 to 60,000.   The said (B) component contains the photopolymerizable compound which has 4-40 C2-C6 oxyalkylene units in a molecule | numerator, It is any one of Claims 1-7 characterized by the above-mentioned. Photosensitive element. The photopolymerizable compound having 4 to 40 carbon atoms having 2 to 6 carbon atoms in the molecule is represented by the following general formula (I) or (II). Photosensitive element.

[In Formula (I), R ¹ and R ² each independently represent a hydrogen atom or a methyl group, X ¹ and X ² each independently represent an alkylene group having 2 to 6 carbon atoms, and p and q are p + q = A positive integer selected to be 4 to 40. ]

[Wherein, R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, Y ¹ , Y ² and Y ³ 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 according to claim 1, wherein the component (C) contains a 2,4,5-triarylimidazole dimer.   The blending amount of the component (B) is 30 to 60 parts by weight with the total amount of the component (A) and the component (B) being 100 parts by weight, and the blending amount of the component (C) is the component (A) and It is 0.1-20 weight part with respect to 100 weight part of total amounts of the said (B) component, The photosensitive element as described in any one of Claims 1-10 characterized by the above-mentioned.   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 laminating the photosensitive element according to any one of claims 1 to 12 on a circuit forming substrate in the order of the photosensitive layer and the resin film;
An exposure step of irradiating a predetermined portion of the photosensitive layer through the resin film with an actinic ray 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 13.

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