JP2020076913A - Method for producing coat and printed wiring board - Google Patents

Abstract

To provide a method for producing a coat of such a shape that has high resolution, when the coat is produced by exposing a coating of a photosensitive resin composition and developing it.SOLUTION: A method for producing a coat includes forming a coating from a photosensitive resin composition, irradiating the coating with light from a light source for exposure, and developing the exposed coating with alkali solution. The photosensitive resin composition contains a carboxyl group-containing resin (A), an unsaturated compound (B), a photopolymerization initiator (C), and an epoxy resin (D). The light irradiated to the coating includes a predetermined wavelength of light.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a method for producing a coating and a printed wiring board, and more particularly to a method for producing a coating by exposing a coating containing a photosensitive resin composition, and a printed wiring board provided with this coating.

  BACKGROUND ART Conventionally, various curable resin compositions have been used for forming electrically insulating layers such as solder resist layers, plating resist layers, etching resist layers, and interlayer insulating layers of printed wiring boards. In the photosensitive resin composition, an electrically insulating layer is formed by irradiating light such as ultraviolet rays to cure the photosensitive resin composition and heating it as necessary.

  For example, in Patent Document 1, a photosensitive resin composition is proposed in which a pattern latent image is formed by a direct drawing method (direct drawing method) using light from a lamp that generates ultraviolet rays, and the pattern latent image is developed with an aqueous alkaline solution. Has been done. When the dry coating film of this photosensitive resin composition is irradiated with light in the wavelength range of 355 to 375 nm and light in the wavelength range of 405 nm, the photosensitive resin composition is highly sensitive to the above wavelength range and wavelength. A thick film electrical insulating layer or the like can be produced even by direct exposure.

JP, 2008-146044, A

  In Patent Document 1, the layer formed from the photosensitive resin composition has excellent properties such as insulation, acid / alkali resistance, and plating resistance required for the insulating layer.

  However, when a coating film is produced by exposing and then developing a coating film of such a photosensitive resin composition, it is not easy for the shape of the coating film to have high resolution. Therefore, for example, when forming a film having pores, it is difficult to sharpen the shape of the pores.

  An object of the present invention is to provide a method for producing a film in which the shape of the film may have high resolution when the film is produced by exposing and then developing the coating film of the photosensitive resin composition. is there.

  Another object of the present invention is to provide a printed wiring board provided with the film manufactured by the above manufacturing method.

  A method for producing a coating film according to an aspect of the present invention, by disposing a photosensitive resin composition on a substrate, a step of forming a coating film on the substrate, and a light emitted from a light source on the coating film. The method includes the steps of irradiating and exposing, and developing the coating film after the exposure with an alkaline solution. The photosensitive resin composition includes a carboxyl group-containing resin (A), an unsaturated compound (B) having at least one ethylenically unsaturated bond in one molecule, a photopolymerization initiator (C), and an epoxy resin. And (D). The light absorption spectrum of the photopolymerization initiator (C) has a first absorption in the wavelength range of 350 nm to 370 nm and a second absorption in the wavelength range of longer than 370 nm and 415 nm or less. The spectrum of the light applied to the coating film in the exposing step has a first intensity distribution at a wavelength overlapping the wavelength of the first absorption within a wavelength range of 350 nm or more and 370 nm or less and 415 nm or less longer than 370 nm. A second intensity distribution in a wavelength range that overlaps the wavelength of the second absorption and a third intensity distribution in a wavelength range of 305 nm to 325 nm, and 200 nm to 500 nm. The total percentage of the area under the curve of the wavelength range shorter than 280 nm and 200 nm and the area under the curve of the wavelength range longer than 415 nm and 500 nm to the area under the curve of the wavelength range is 5% or less.

  A printed wiring board according to one aspect of the present invention includes a conductive layer and an insulating layer overlapping the conductive layer. The insulating layer includes a film produced by the method for producing the film.

  In the method for producing a coating film according to one aspect of the present invention, when the coating film of the photosensitive resin composition is exposed and then developed to produce the coating film, the shape of the coating film can have high resolution.

  According to one aspect of the present invention, a printed wiring board having a film with high resolution can be obtained.

FIG. 1 is a diagram showing a spectrum of light emitted from an ultra-high pressure mercury lamp which is a light source in an example. FIG. 2A is a diagram showing an example of the shape of the film when the exposure condition is the condition A, and FIG. 2B is a diagram showing an example of the film shape when the exposure condition is the condition C in the example. FIG. 2C is a diagram showing an example of the shape of the film when the exposure condition is condition D. 3A to 3E are cross-sectional views showing a process of manufacturing a multilayer printed wiring board according to an embodiment of the present invention.

  The photosensitive resin composition in this embodiment will be described.

  The photosensitive resin composition of the present embodiment comprises a carboxyl group-containing resin (A), an unsaturated compound (B) having at least one ethylenically unsaturated bond in one molecule, a photopolymerization initiator (C). , Epoxy resin (D). The details of each component of the photosensitive resin composition will be described later.

  In the present embodiment, the light absorption spectrum of the photopolymerization initiator (C) has a first absorption in the wavelength range of 350 nm to 370 nm and a second absorption in the wavelength range of longer than 370 nm and 415 nm or less. Have and. The first absorption may be in the entire wavelength range of 350 nm or more and 370 nm or less, or may be in a part of the wavelength range of 350 nm or more and 370 nm or less. The same applies to the second absorption (absorption in the wavelength range longer than 370 nm and not more than 415 nm) and the third absorption (absorption in the wavelength range not less than 305 nm and not more than 325 nm) described later.

  In the present embodiment, by placing the photosensitive resin composition on the substrate, a coating film is formed on the substrate, the coating film is exposed to light for exposure, and the coating film after exposure is treated with an alkaline solution. A film can be formed by developing with. That is, the method for producing a film containing a photosensitive resin composition is a step of forming a coating film on a substrate by arranging the photosensitive resin composition on the substrate, and a light source is emitted to the coating film. The method includes the steps of exposing to light and exposing, and the step of developing the coating film after exposure with an alkaline solution. The spectrum of the light applied to the coating film in the exposing step has a first intensity distribution in the wavelength range of 350 nm or more and 370 nm or less and a wavelength that overlaps the wavelength of the first absorption, and a wavelength longer than 370 nm and 415 nm or less. It has a second intensity distribution in a wavelength range that overlaps the wavelength of the second absorption and a third intensity distribution in a wavelength range of 305 nm or more and 325 nm or less. Further, in the spectrum of this light, the sum of the area under the curve in the wavelength range from 280 nm to 200 nm and the area under the curve in the wavelength range from 415 nm to 500 nm with respect to the area under the curve in the wavelength range from 200 nm to 500 nm. The percentage is 5% or less. Therefore, when a coating formed from the photosensitive resin composition is exposed and then developed to produce a coating, the shape of the coating has a high resolution. When the film has pores, the pores of the film can be sharply formed. Note that the strength is a strength having a value larger than 0.

  When a coating is produced by exposing a coating of a photosensitive resin composition to light and then developing the coating, it is presumed that the shape of the coating has a high resolution because of the following reasons.

  In the present embodiment, as described above, the light absorption spectrum of the photopolymerization initiator (C) has the first absorption in the wavelength range of 350 nm or more and 370 nm or less, and the spectrum of the light with which the coating film is irradiated is It has a first intensity distribution at a wavelength overlapping the wavelength of the first absorption within a wavelength range of 350 nm or more and 370 nm or less. Therefore, the photopolymerization initiator (C) can absorb light in the wavelength range of 350 nm to 370 nm in the coating film to start the photopolymerization reaction. Thereby, the photopolymerization initiator (C) is efficiently activated by the light with which the coating film is irradiated, and it becomes easy to promote the reaction of the entire photosensitive resin composition. Therefore, it is considered that the light having a wavelength of 350 nm or more and 370 nm or less contributes to the reactivity of the entire photosensitive resin composition and can improve the reactivity of the photosensitive resin composition. In one aspect of this embodiment, the light with which the coating film is irradiated includes i-rays having a wavelength of 365 nm, and the first intensity distribution has an intensity at a wavelength of 365 nm.

  In addition, as described above, the light absorption spectrum of the photopolymerization initiator (C) has a second absorption in the wavelength range of longer than 370 nm and not longer than 415 nm, and the spectrum of the light with which the coating film is irradiated is longer than 370 nm. It has a second intensity distribution at a wavelength that overlaps the wavelength of the second absorption within a long wavelength range of 415 nm or less. Therefore, the photopolymerization initiator (C) in the coating film can absorb the light within the wavelength range of longer than 370 nm and shorter than 415 nm to start the photopolymerization reaction. Therefore, it is considered that good curability can be realized especially in the deep portion of the coating film of the photosensitive resin composition. In addition, the photopolymerization initiator (C) can exhibit a photobleaching effect by absorbing light having a wavelength of 350 nm or more and 370 nm or less as described above. That is, it can also act to improve the transmittance of light having a wavelength effective for deep hardening. It is considered that this makes it possible to improve the deep-part curability of the coating film of the photosensitive resin composition. In particular, a wavelength at which the second absorption includes at least absorption in the wavelength range longer than 400 nm and less than 415 nm, and the second intensity distribution overlaps the wavelength of the second absorption in the wavelength range longer than 400 nm and less than 415 nm. It is preferable to include at least the intensity distribution in. In this case, the photopolymerization initiator (C) in the coating film can absorb light in the wavelength range of longer than 400 nm and not longer than 415 nm to start the photopolymerization reaction. This makes it possible to achieve better curability in the deep portion of the coating film of the photosensitive resin composition.

  Furthermore, the spectrum of the light with which the coating film of the photosensitive resin composition is irradiated has a third intensity distribution within the wavelength range of 305 nm to 325 nm, whereby the surface of the coating film of the photosensitive resin composition is It is considered that the curability can be improved. This is because the carboxyl group-containing resin (A) in the photosensitive resin composition absorbs light in the wavelength range of 305 nm or more and 325 nm or less, so that the photopolymerization reaction can be initiated by a photosensitizing effect or the like. Is considered to be. In addition, light having a wavelength of 305 nm or more and 325 nm or less originally tends to be scattered in the coating film, but since the carboxyl group-containing resin (A) absorbs this light as described above, light scattering occurs in the coating film. Hateful. Therefore, it is considered that the resolution is less likely to decrease.

  In particular, the light absorption spectrum of the photopolymerization initiator (C) further has a third absorption within the wavelength range of 305 nm to 325 nm, and the third intensity distribution within the wavelength range of 305 nm to 325 nm. When the photopolymerization initiator (C) contains at least an intensity distribution having a wavelength overlapping with the third absorption wavelength, the photopolymerization initiator (C) can start a photopolymerization reaction by absorbing light having a wavelength of 305 nm to 325 nm. it can. Therefore, the surface curability of the coating film is likely to increase. Further, as described above, light having a wavelength of 305 nm or more and 325 nm or less is less likely to be scattered in the coating film, so that the decrease in resolution due to the photopolymerization initiator (C) is less likely to occur.

  Further, as described above, the spectrum of the light radiated to the coating film has an area under the curve in the wavelength range of 280 nm to 200 nm and a wavelength in the wavelength range of 415 nm to 500 nm for the area under the curve in the wavelength range of 200 nm to 500 nm. The total percentage of the area under the curve is 5% or less. For this reason, it is possible to prevent light within these wavelength ranges from being scattered in the coating film of the photosensitive resin composition. This makes it possible to prevent the resolution of the coating film of the photosensitive resin composition from being lowered due to light scattering. Therefore, for example, when a film having pores is formed from the photosensitive resin composition by the photolithography method, it is possible to prevent the shape of the pores from being adversely affected.

  Thus, in the present embodiment, when the coating film of the photosensitive resin composition is exposed to light of a specific wavelength, the photosensitive resin composition is not irradiated with light of a wavelength unnecessary for reaction or curing. The film shape of can have a high resolution.

  The components constituting the photosensitive resin composition according to this embodiment will be described in detail. In the following description, “(meth) acrylic” means at least one of “acrylic” and “methacrylic”. For example, (meth) acrylate means at least one of acrylate and methacrylate.

  The carboxyl group-containing resin (A) preferably contains a carboxyl group-containing resin having an ethylenically unsaturated group. In this case, the carboxyl group-containing resin (A) has photoreactivity. Therefore, the carboxyl group-containing resin (A) can impart photosensitivity, specifically, ultraviolet curability, to the photosensitive resin composition together with the unsaturated compound (B).

  The carboxyl group-containing resin (A) preferably contains a carboxyl group-containing resin having an aromatic ring. In this case, high heat resistance and insulation reliability can be imparted to the cured product of the photosensitive resin composition. Further, due to the aromatic ring, the light absorption spectrum of the carboxyl group-containing resin (A) may have absorption in the wavelength range of 305 nm to 325 nm, so that light scattering in the coating film during exposure is caused. In particular, it hardly occurs and the resolution is particularly improved.

  The carboxyl group-containing resin (A) more preferably contains a carboxyl group-containing resin having a polycyclic aromatic ring selected from the group consisting of a biphenyl skeleton, a naphthalene skeleton, a fluorene skeleton and an anthracene skeleton. Since the carboxyl group-containing resin (A) contains a polycyclic aromatic ring of any one of a biphenyl skeleton, a naphthalene skeleton, a fluorene skeleton, and an anthracene skeleton, a cured product of the photosensitive resin composition has higher heat resistance and Insulation reliability can be provided. Further, in this case, since the light absorption spectrum of the carboxyl group-containing resin (A) can have a particularly large absorption in the wavelength range of 305 nm to 325 nm, light scattering can be less likely to occur at the time of exposure. The image quality is particularly improved. The carboxyl group-containing resin (A) more preferably contains the carboxyl group-containing resin (A1) having a bisphenolfluorene skeleton. In this case, due to the bisphenolfluorene skeleton, the light absorption spectrum of the carboxyl group-containing resin (A1) can have a particularly large absorption in the wavelength range of 305 nm to 325 nm, so that light scattering during exposure is prevented. In particular, it can be made less likely to occur, and the reduction in resolution can be made less likely to occur. Thereby, when the coating film of the photosensitive resin composition is exposed and then developed to produce a coating film, the shape of the coating film may have higher resolution. Therefore, for example, when a film having pores is formed from the photosensitive resin composition by the photolithography method, it is possible to prevent the shape of the pores from being adversely affected. Further, in this case, it is possible to impart higher heat resistance and insulation reliability to the cured product of the photosensitive resin composition.

The carboxyl group-containing resin (A1) having a bisphenolfluorene skeleton is, for example, a carboxylic acid containing an epoxy compound (a1) having a bisphenolfluorene skeleton represented by the following formula (1) and an unsaturated group-containing carboxylic acid (a2-1). It includes an intermediate which is a reaction product with an acid (a2) and a reaction product with an acid anhydride (a3). In the formula (1), R _{1 to} R ₈ are each independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or halogen. The carboxyl group-containing resin (A1) is an epoxy compound (a1) having a bisphenolfluorene skeleton (S1) represented by the following formula (1) and a carboxylic acid (a2) containing an unsaturated group-containing carboxylic acid (a2-1). Are reacted, and the intermediate thus obtained is reacted with the acid anhydride (a3) to synthesize.

Each of R _{1 to} R ₈ in the formula (1) may be hydrogen, but may be an alkyl group having 1 to 5 carbon atoms or halogen. This is because, even if hydrogen in the aromatic ring is replaced with a low molecular weight alkyl group or halogen, the physical properties of the carboxyl group-containing resin (A1) are not adversely affected, and rather the photosensitive resin composition containing the carboxyl group-containing resin (A1) This is because the heat resistance or flame retardancy of the cured product may be improved in some cases.

  When the carboxyl group-containing resin (A1) has a bisphenolfluorene skeleton derived from the epoxy compound (a1), the cured product of the photosensitive resin composition containing the carboxyl group-containing resin (A1) has high heat resistance and insulation. Reliability can be added.

  The carboxyl group-containing resin (A1) will be described more specifically. In order to synthesize the carboxyl group-containing resin (A1), first, at least a part of the epoxy group in the epoxy compound (a1) having the bisphenolfluorene skeleton represented by the formula (1) and the unsaturated group-containing carboxylic acid (a2- The intermediate is synthesized by reacting with the carboxylic acid (a2) containing 1). The synthesis of the intermediate is defined as the first reaction. The intermediate has a secondary hydroxyl group produced by a ring-opening addition reaction of an epoxy group and a carboxylic acid (a2) containing an unsaturated group-containing carboxylic acid (a2-1). Next, the secondary hydroxyl group in the intermediate is reacted with the acid anhydride (a3). Thereby, the carboxyl group-containing resin (A1) can be synthesized. The reaction between the intermediate and the acid anhydride (a3) is defined as the second reaction. The acid anhydride (a3) may include an acid monoanhydride and an acid dianhydride. The acid monoanhydride is a compound having one acid anhydride group obtained by dehydration condensation of two carboxyl groups in one molecule. An acid dianhydride is a compound having two acid anhydride groups obtained by dehydration condensation of four carboxyl groups in one molecule.

  The carboxyl group-containing resin (A1) may contain unreacted components in the intermediate. When the acid anhydride (a3) contains an acid monoanhydride and an acid dianhydride, the carboxyl group-containing resin (A1) includes a component in the intermediate, a component in the acid monoanhydride, and an acid dianhydride. In addition to the reaction product with the component in the intermediate, the reaction product with the component in the intermediate and the component in the acid monoanhydride, and the reaction product with the component in the intermediate and the component in the acid dianhydride. One or both may be contained. That is, the carboxyl group-containing resin (A1) may be a mixture containing a plurality of compounds having different structures such as these.

  The carboxyl group-containing resin (A1) has photoreactivity by having an ethylenically unsaturated group derived from the unsaturated group-containing carboxylic acid (a2-1). Therefore, the carboxyl group-containing resin (A1) can impart photosensitivity, specifically, ultraviolet curability, to the photosensitive resin composition. Further, the carboxyl group-containing resin (A1) has a carboxyl group derived from the acid anhydride (a3), so that the photosensitive resin composition contains at least one of an alkali metal salt and an alkali metal hydroxide. Developability with an alkaline aqueous solution can be imparted.

  The weight average molecular weight of the carboxyl group-containing resin (A1) is preferably in the range of 700 or more and 10,000 or less. When the weight average molecular weight is 700 or more, the insulating property of the cured product of the photosensitive resin composition can be improved and the dielectric loss tangent can be reduced. When the weight average molecular weight is 10,000 or less, the developability of the photosensitive resin composition with an alkaline aqueous solution is particularly improved. The weight average molecular weight is more preferably 900 or more, and particularly preferably 1000 or more. Further, the weight average molecular weight is more preferably in the range of 8,000 or less, and particularly preferably in the range of 5,000 or less.

  The polydispersity of the carboxyl group-containing resin (A1) is preferably in the range of 1.0 or more and 4.8 or less. In this case, excellent developability can be imparted to the photosensitive resin composition while ensuring good insulation of the cured product formed from the photosensitive resin composition. The polydispersity of the carboxyl group-containing resin (A1) is more preferably 1.1 or more and 4.0 or less, and further preferably 1.2 or more and 2.8 or less.

  The number average molecular weight and the molecular weight distribution of the carboxyl group-containing resin (A1) as described above are such that the carboxyl group-containing resin (A1) has an unreacted component in the intermediate, a component in the intermediate and an acid monoanhydride. A reaction product between the component and the component in the acid dianhydride, a reaction product between the component in the intermediate and the component in the acid monoanhydride, a reaction product between the component in the intermediate and the component in the acid dianhydride, This can be achieved by being a mixture containing various components in an appropriate amount. More specifically, it is achieved by controlling parameters such as the average molecular weight of the epoxy compound (a1), the amount of acid monoanhydride with respect to the epoxy compound (a1), and the amount of acid dianhydride with respect to the epoxy compound (a1). it can.

  The polydispersity is the value (Mw / Mn) of the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the carboxyl group-containing resin (A1).

  The solid acid value of the carboxyl group-containing resin (A1) is preferably in the range of 60 mgKOH / g or more and 140 mgKOH / g or less. In this case, the developability of the photosensitive resin composition is particularly improved. More preferably, the acid value is in the range of 80 mgKOH / g or more and 135 mgKOH / g or less, and even more preferably the acid value is in the range of 90 mgKOH / g or more and 130 mgKOH / g or less.

  The molecular weight of the carboxyl group-containing resin (A1) can be adjusted by crosslinking the acid dianhydride. In this case, a carboxyl group-containing resin (A1) having an adjusted acid value and molecular weight is obtained. That is, by controlling the amount of the acid dianhydride contained in the acid anhydride (a3), the molecular weight and acid value of the carboxyl group-containing resin (A1) can be easily adjusted. The molecular weight of the carboxyl group-containing resin (A1) is calculated from the result of measurement by gel permeation chromatography under the following conditions.

GPC device: SHOWDEX SYSTEM 11, manufactured by Showa Denko KK,
Column: 4 series of SHODEX KF-800P, KF-005, KF-003, KF-001,
Mobile phase: THF,
Flow rate: 1 ml / min,
Column temperature: 45 ℃,
Detector: RI,
Conversion: polystyrene.

  Raw materials for the carboxyl group-containing resin (A1) and reaction conditions during the synthesis of the carboxyl group-containing resin (A1) will be described in detail.

  The epoxy compound (a1) has a structure represented by the following formula (2), for example. N in Formula (2) is an integer in the range of 0-20, for example. In order to properly control the molecular weight of the carboxyl group-containing resin (A1), the average of n is particularly preferably in the range of 0 to 1. When the average of n is in the range of 0 to 1, even when the acid anhydride (a3) contains an acid dianhydride, it is easy to suppress an excessive increase in the molecular weight.

  The carboxylic acid (a2) includes the unsaturated group-containing carboxylic acid (a2-1). The carboxylic acid (a2) may contain only the unsaturated group-containing carboxylic acid (a2-1). Alternatively, the carboxylic acid (a2) may contain a carboxylic acid other than the unsaturated group-containing carboxylic acid (a2-1) and the unsaturated group-containing carboxylic acid (a2-1).

  The unsaturated group-containing carboxylic acid (a2-1) can contain, for example, a compound having only one ethylenically unsaturated group. More specifically, the unsaturated group-containing carboxylic acid (a2-1) is, for example, acrylic acid, methacrylic acid, ω-carboxy-polycaprolactone (n≈2) monoacrylate, crotonic acid, cinnamic acid, 2-acryloyloxy. Ethyl succinic acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxyethyl phthalic acid, 2-methacryloyloxyethyl phthalic acid, 2-acryloyloxypropyl phthalic acid, 2-methacryloyloxypropyl phthalic acid, 2-acryloyloxyethyl maleic acid Acid, 2-methacryloyloxyethyl maleic acid, β-carboxyethyl acrylate, 2-acryloyloxyethyl tetrahydrophthalic acid, 2-methacryloyloxyethyl tetrahydrophthalic acid, 2-acryloyloxyethyl hexahydrophthalic acid, and 2-methacryloyloxyethyl It may contain one or more compounds selected from the group consisting of hexahydrophthalic acid. Preferably, the unsaturated group-containing carboxylic acid (a2-1) contains acrylic acid.

  The carboxylic acid (a2) may include a polybasic acid (a2-2). The polybasic acid (a2-2) is an acid capable of substituting two or more hydrogen atoms with metal atoms in one molecule. The polybasic acid (a2-2) preferably has two or more carboxyl groups. In this case, the epoxy compound (a1) reacts with both the unsaturated group-containing carboxylic acid (a2-1) and the polybasic acid (a2-2). When the polybasic acid (a2-1) crosslinks the epoxy groups present in the two molecules of the epoxy compound (a1), an increase in the molecular weight can be obtained. Thereby, the insulation of the cured product of the photosensitive resin composition can be improved and the dielectric loss tangent can be reduced.

  The polybasic acid (a2-2) preferably contains a dicarboxylic acid. The polybasic acid (a2-2) is, for example, 4-cyclohexene-1,2-dicarboxylic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, It may contain one or more compounds selected from the group consisting of maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid. Preferably, the polybasic acid (a2-2) contains 4-cyclohexene-1,2-dicarboxylic acid.

  In reacting the epoxy compound (a1) with the carboxylic acid (a2), an appropriate method can be adopted. For example, a carboxylic acid (a2) is added to a solvent solution of an epoxy compound (a1), and if necessary, a thermal polymerization inhibitor and a catalyst are added, and the mixture is stirred and mixed to obtain a reactive solution. An intermediate can be obtained by reacting this reactive solution at a temperature of preferably 60 ° C. or higher and 150 ° C. or lower, particularly preferably 80 ° C. or higher and 120 ° C. or lower by a conventional method. Examples of the solvent include ketones such as methyl ethyl ketone and cyclohexanone, and aromatic hydrocarbons such as toluene and xylene, and ethyl acetate, butyl acetate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbitol acetate, and diethylene glycol monoethyl ether. At least one component selected from the group consisting of acetates, acetic acid esters such as propylene glycol monomethyl ether acetate, and dialkyl glycol ethers can be contained. The thermal polymerization inhibitor contains, for example, at least one of hydroquinone and hydroquinone monomethyl ether. The catalyst is at least selected from the group consisting of tertiary amines such as benzyldimethylamine and triethylamine, quaternary ammonium salts such as trimethylbenzylammonium chloride and methyltriethylammonium chloride, triphenylphosphine, and triphenylstibine. It may contain one kind of ingredient.

  It is particularly preferred that the catalyst contains triphenylphosphine. That is, it is preferable to react the epoxy compound (a1) with the carboxylic acid (a2) in the presence of triphenylphosphine. In this case, the ring-opening addition reaction between the epoxy group in the epoxy compound (a1) and the carboxylic acid (a2) is particularly promoted and a reaction rate (conversion rate) of 95% or more, or 97% or more, or almost 100% is achieved. It is possible to Further, the occurrence of ion migration in the layer containing the cured product of the photosensitive resin composition is suppressed, and the insulating property of the layer containing the cured product is improved.

  When the epoxy compound (a1) is reacted with the carboxylic acid (a2), the amount of the carboxylic acid (a2) is 0.5 mol or more and 1.2 mol or less based on 1 mol of the epoxy group of the epoxy compound (a1). Preferably. In this case, excellent photosensitivity and stability of the photosensitive resin composition can be obtained. From the same viewpoint, the amount of the unsaturated group-containing carboxylic acid (a2-1) with respect to 1 mol of the epoxy group of the epoxy compound (a1) is preferably 0.5 mol or more and 1.2 mol or less. Alternatively, when the carboxylic acid (a2) contains a carboxylic acid other than the unsaturated group-containing carboxylic acid (a2-1), the unsaturated group-containing carboxylic acid (a2- The amount of 1) may be in the range of 0.5 mol or more and 0.95 mol or less. Moreover, when the carboxylic acid (a2) contains a polybasic acid (a2-2), the amount of the polybasic acid (a2-2) is 0.025 mol or more per 0.1 mol of the epoxy group of the epoxy compound (a1). It is preferably within the range of 25 mol or less. In this case, excellent photosensitivity and stability of the photosensitive resin composition can be obtained.

  It is also preferable to react the epoxy compound (a1) and the carboxylic acid (a2) under air bubbling. In this case, the addition polymerization reaction of the unsaturated group can be suppressed, and the increase in the molecular weight of the intermediate and the gelation of the solution of the intermediate can be suppressed. Further, excessive coloring of the carboxyl group-containing resin (A1) which is the final product can be suppressed.

  The intermediate thus obtained has a hydroxyl group generated by the reaction between the epoxy group in the epoxy compound (a1) and the carboxyl group in the carboxylic acid (a2).

  The acid anhydride (a3) preferably contains acid monoanhydride. An acid monoanhydride is a compound having one acid anhydride group.

  The acid monoanhydride can include an anhydride of a dicarboxylic acid. Examples of the acid monoanhydride include 1,2,3,6-tetrahydrophthalic anhydride, phthalic anhydride, succinic anhydride, methylsuccinic anhydride, maleic anhydride, citraconic anhydride, glutaric anhydride, Itaconic anhydride, methyl tetrahydrophthalic anhydride, methyl nadic acid anhydride, hexahydrophthalic anhydride, cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride, and methylhexahydrophthalic anhydride It can contain one or more compounds selected from the group consisting of the following: It is particularly preferable that the acid monoanhydride contains 1,2,3,6-tetrahydrophthalic anhydride. In this case, the insulating property of the cured product of the photosensitive resin composition can be improved while ensuring the good developability of the photosensitive resin composition. The content of 1,2,3,6-tetrahydrophthalic anhydride is preferably 20 mol% or more and 100 mol% or less, and 40 mol% or more and 100 mol% or less with respect to the entire acid monoanhydride. Is more preferable, but not limited to this.

  The acid anhydride (a3) preferably contains an acid dianhydride. The acid dianhydride is a compound having two acid anhydride groups. The acid dianhydride can contain an anhydride of tetracarboxylic acid. Examples of the acid dianhydride include 1,2,4,5-benzenetetracarboxylic acid dianhydride, benzophenone tetracarboxylic acid dianhydride, methylcyclohexene tetracarboxylic acid dianhydride, tetracarboxylic acid dianhydride and naphthalene-1. , 4,5,8-Tetracarboxylic acid dianhydride, ethylene tetracarboxylic acid dianhydride, 9,9'-bis (3,4-dicarboxyphenyl) fluorene dianhydride, glycerin bisanhydrotrimellitate mono Acetate, ethylene glycol bisanhydrotrimellitate, 3,3 ', 4,4'-diphenylsulfone tetracarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5 (tetrahydro-2, 5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione, 1,2,3,4-butanetetracarboxylic dianhydride and 3,3 ', 4,4'- It can contain at least one compound selected from the group consisting of biphenyltetracarboxylic dianhydride. The acid dianhydride preferably contains an acid dianhydride having an aromatic ring. It is particularly preferable that the acid dianhydride contains 3,3 ′, 4,4′-biphenyltetracarboxylic acid dianhydride. In this case, the insulating property of the cured product of the photosensitive resin composition can be improved while ensuring the good developability of the photosensitive resin composition. Further, the transparency of the photosensitive resin composition is improved, and the resolution is improved accordingly. The amount of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride is preferably 20 mol% or more and 100 mol% or less, and 40 mol% or more and 100 mol% or less with respect to the entire acid dianhydride. It is more preferable that it is within the range of not more than%, but it is not limited thereto.

  In reacting the intermediate with the acid anhydride (a3), an appropriate method can be adopted. For example, the acid anhydride (a3) is added to the solvent solution of the intermediate, and if necessary, a thermal polymerization inhibitor and a catalyst are added, and the mixture is stirred and mixed to obtain a reactive solution. The carboxyl group-containing resin (A1) is obtained by reacting this reactive solution by a conventional method at a temperature of preferably 60 ° C. or higher and 150 ° C. or lower, particularly preferably 80 ° C. or higher and 120 ° C. or lower. As the solvent, the catalyst and the polymerization inhibitor, appropriate ones can be used, and the solvent, the catalyst and the polymerization inhibitor used during the synthesis of the intermediate can be used as they are.

  It is particularly preferred that the catalyst contains triphenylphosphine. That is, it is preferable to react the intermediate with the acid anhydride (a3) in the presence of triphenylphosphine. In this case, the reaction between the secondary hydroxyl group and the acid anhydride (a3) in the intermediate is particularly promoted, and the reaction rate (conversion rate) of 90% or more, 95% or more, 97% or more, or almost 100% is achieved. It is possible to Further, the occurrence of ion migration in the layer containing the cured product of the photosensitive resin composition is suppressed, and the insulating property of the layer containing the cured product is further improved.

  It is also preferable to react the intermediate and the acid anhydride (a3) under air bubbling. In this case, the excessive increase in the molecular weight of the generated carboxyl group-containing resin (A1) is suppressed, so that the developability of the photosensitive resin composition with an alkaline aqueous solution is particularly improved.

  The carboxyl group-containing resin (A) may include a carboxyl group-containing resin that has an aromatic ring and does not have photopolymerizability. The carboxyl group-containing resin having an aromatic ring and not photopolymerizable contains, for example, a polymer of an ethylenically unsaturated monomer containing an ethylenically unsaturated compound having a carboxyl group. Examples of the ethylenically unsaturated compound having a carboxyl group include acrylic acid, methacrylic acid, ω-carboxy-polycaprolactone (n≈2) monoacrylate, 2- (meth) acryloyloxyethyl phthalate, and 2- (meth) acryloyloxy. It can contain compounds such as ethyl-2-hydroxyethyl phthalate. The ethylenically unsaturated compound having a carboxyl group can also contain a reaction product of pentaerythritol triacrylate, pentaerythritol trimethacrylate, etc. and a dibasic acid anhydride. The ethylenically unsaturated monomer is a carboxyl group such as a linear or branched aliphatic or alicyclic (however, a ring may partially have an unsaturated bond) (meth) acrylic acid ester. You may further contain the ethylenically unsaturated compound which does not have.

  The carboxyl group-containing resin (A) may contain a resin other than the carboxyl group-containing resin (A1), that is, a carboxyl group-containing resin having no bisphenolfluorene skeleton (hereinafter, also referred to as a carboxyl group-containing resin (A2)). Good.

  The carboxyl group-containing resin (A2) can contain, for example, a compound having a carboxyl group and not having photopolymerizability (hereinafter referred to as component (A2-1)). The component (A2-1) contains, for example, a polymer of an ethylenically unsaturated monomer containing an ethylenically unsaturated compound having a carboxyl group. The ethylenically unsaturated compound having a carboxyl group can contain a compound such as acrylic acid, methacrylic acid, or ω-carboxy-polycaprolactone (n≈2) monoacrylate. The ethylenically unsaturated compound having a carboxyl group can also contain a reaction product of pentaerythritol triacrylate, pentaerythritol trimethacrylate, etc. and a dibasic acid anhydride. The ethylenically unsaturated monomer is 2- (meth) acryloyloxyethyl phthalate, 2- (meth) acryloyloxyethyl-2-hydroxyethyl phthalate, a linear or branched aliphatic or alicyclic group (however, You may further contain the ethylenically unsaturated compound which does not have a carboxyl group, such as (meth) acrylic acid ester of a part which may have an unsaturated bond in the ring.

  The carboxyl group-containing resin (A2) may contain a compound having a carboxyl group and an ethylenically unsaturated group (hereinafter referred to as component (A2-2)). The carboxyl group-containing resin (A2) may contain only the component (A2-2). The component (A2-2) is, for example, an intermediate which is a reaction product of an epoxy compound (x1) having two or more epoxy groups in one molecule and an ethylenically unsaturated compound (x2), a polyvalent carboxylic acid, and It contains a resin (referred to as a first resin (x)) which is a reaction product with at least one compound (x3) selected from the group of the anhydrides. The first resin (x) is obtained by, for example, adding the compound (x3) to an intermediate obtained by reacting the epoxy group in the epoxy compound (x1) with the carboxyl group in the ethylenically unsaturated compound (x2). Can be obtained. The epoxy compound (x1) can contain an appropriate epoxy compound such as a cresol novolac type epoxy compound, a phenol novolac type epoxy compound, and a biphenyl novolac type epoxy compound. In particular, the epoxy compound (x1) preferably contains at least one compound selected from the group consisting of biphenyl novolac type epoxy compounds and cresol novolac type epoxy compounds. The epoxy compound (x1) may contain only a biphenyl novolac type epoxy compound, or may contain only a cresol novolac type epoxy compound. In this case, since the main chain of the epoxy compound (x1) contains an aromatic ring, the degree to which the cured product of the photosensitive resin composition is significantly corroded by an oxidizing agent containing, for example, potassium permanganate is reduced. it can. The epoxy compound (x1) may contain a polymer of the ethylenically unsaturated compound (z). The ethylenically unsaturated compound (z) contains, for example, a compound (z1) having an epoxy group such as glycidyl (meth) acrylate, or does not further have an epoxy group such as 2- (meth) acryloyloxyethyl phthalate. It contains the compound (z2). The ethylenically unsaturated compound (x2) preferably contains at least one of acrylic acid and methacrylic acid. The compound (x3) contains at least one compound selected from the group consisting of polycarboxylic acids such as phthalic acid, tetrahydrophthalic acid and methyltetrahydrophthalic acid, and anhydrides of these polycarboxylic acids. .. In particular, the compound (x3) preferably contains at least one polyvalent carboxylic acid selected from the group of phthalic acid, tetrahydrophthalic acid and methyltetrahydrophthalic acid.

  The component (A2-2) is a resin which is a reaction product of a polymer of an ethylenically unsaturated monomer containing an ethylenically unsaturated compound having a carboxyl group and an ethylenically unsaturated compound having an epoxy group (second Resin (y)) may be contained. The ethylenically unsaturated monomer may further contain an ethylenically unsaturated compound having no carboxyl group. The second resin (y) is obtained by reacting an ethylenically unsaturated compound having an epoxy group with a part of the carboxyl groups in the polymer. The ethylenically unsaturated monomer may further contain an ethylenically unsaturated compound having no carboxyl group. Examples of the ethylenically unsaturated compound having a carboxyl group include compounds such as acrylic acid, methacrylic acid, ω-carboxy-polycaprolactone (n≈2) monoacrylate, pentaerythritol triacrylate, and pentaerythritol trimethacrylate. The ethylenically unsaturated compound having no carboxyl group is, for example, 2- (meth) acryloyloxyethyl phthalate, 2- (meth) acryloyloxyethyl-2-hydroxyethyl phthalate, linear or branched aliphatic or fat. It contains a compound such as a (meth) acrylic acid ester of a cyclic group (however, it may have an unsaturated bond partially in the ring). The ethylenically unsaturated compound having an epoxy group preferably contains glycidyl (meth) acrylate.

  The carboxyl group-containing resin (A) contains only the carboxyl group-containing resin (A1), only the carboxyl group-containing resin (A2), or contains the carboxyl group-containing resin (A1) and the carboxyl group-containing resin (A2). In order to obtain high transparency of the photosensitive resin composition and to reduce the dielectric loss tangent of the cured product of the photosensitive resin composition, the carboxyl group-containing resin (A) is 30% of the carboxyl group-containing resin (A1). The content is preferably at least mass%, more preferably at least 60 mass%, even more preferably at 100 mass%.

  The content of the carboxyl group-containing resin (A) is preferably in the range of 5 mass% to 85 mass% with respect to the solid content of the photosensitive resin composition, and in the range of 10 mass% to 75 mass%. Is more preferable, the range is more preferably 26% by mass or more and 60% by mass or less, and particularly preferably 30% by mass or more and 45% by mass or less. The solid content is the total amount of all components excluding volatile components such as a solvent from the photosensitive resin composition.

  The solid acid value of the carboxyl group-containing resin (A) is preferably in the range of 40 mgKOH / g or more and 160 mgKOH / g or less. In this case, the stability of the photosensitive resin composition is particularly improved. More preferably, the acid value is in the range of 60 mgKOH / g or more and 140 mgKOH / g or less, more preferably the acid value is in the range of 80 mgKOH / g or more and 135 mgKOH / g or less, and the acid value is 90 mgKOH / g or more and 130 mgKOH / g. It is particularly preferable if it is within the following range.

  The unsaturated compound (B) has at least one ethylenically unsaturated bond in one molecule. The unsaturated compound (B) can impart photocurability to the photosensitive resin composition. The unsaturated compound (B) is, for example, monofunctional (meth) acrylate such as 2-hydroxyethyl (meth) acrylate; and diethylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate. Acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ε-caprolactone modified pentaerythritol hexaacrylate, tricyclodecane diacrylate It can contain at least one compound selected from the group consisting of polyfunctional (meth) acrylates such as methanol di (meth) acrylate.

  In particular, the unsaturated compound (B) preferably contains a trifunctional compound, that is, a compound having three unsaturated bonds in one molecule. In this case, the resolution when exposing and developing the film formed from the photosensitive resin composition is improved, and the developability of the photosensitive resin composition with an alkaline aqueous solution is particularly improved. Trifunctional compounds include, for example, trimethylolpropane tri (meth) acrylate, EO-modified trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, ethoxylated isocyanuric acid tri (meth) acrylate and ε-caprolactone modified. It can contain at least one compound selected from the group consisting of tris- (2-acryloxyethyl) isocyanurate and ethoxylated glycerin tri (meth) acrylate.

  The unsaturated compound (B) also preferably contains a phosphorus-containing compound (phosphorus-containing unsaturated compound). In this case, the flame retardancy of the cured product of the photosensitive resin composition is improved. Examples of the phosphorus-containing unsaturated compound include 2-methacryloyloxyethyl acid phosphate (specific examples are Kyoeisha Chemical Co., Ltd. product numbers light ester P-1M and light ester P-2M) and 2-acryloyloxyethyl acid phosphate. (Specific example is Kyoeisha Chemical Co., Ltd. product number light acrylate P-1A), diphenyl-2-methacryloyloxyethyl phosphate (specific example is Daihachi Co., Ltd. product number MR-260), and Showa Polymer Co., Ltd. Manufactured by HFA series (as a specific example, an addition reaction product of dipentaerythritol hexaacrylate and HCA (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide), HFA-6003, and HFA-6007, product number HFA-3003, which is an addition reaction product of caprolactone-modified dipentaerythritol hexaacrylate, and HCA (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide), and HFA- 6127 etc.) can be included in at least one compound selected from the group consisting of.

  The unsaturated compound (B) may contain a prepolymer. The prepolymer is, for example, at least one selected from the group consisting of prepolymers obtained by polymerizing a monomer having an ethylenically unsaturated bond and then adding an ethylenically unsaturated group, and oligo (meth) acrylate prepolymers. The compound of The oligo (meth) acrylate prepolymers include, for example, epoxy (meth) acrylate, polyester (meth) acrylate, urethane (meth) acrylate, alkyd resin (meth) acrylate, silicone resin (meth) acrylate, and spirane resin (meth) acrylate. It may contain at least one component selected from the group consisting of:

  The unsaturated compound (B) may contain an unsaturated compound (B1) having a bisphenolfluorene skeleton. The unsaturated compound (B1) contains, for example, at least one component selected from the group consisting of bisphenoxyethanolfluorene, bisphenoxyfluorange methacrylate, and 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene. Can be included. Examples of specific products of the unsaturated compound (B1) are Shin-Nakamura Chemical Co., Ltd. product name A-BPEF, Taoka Chemical Co., Ltd. product name TBIS-G and TBIS-MPN, Osaka Gas Chemicals Co., Ltd. Product names EA-200 and EA-1000.

  As described above, the light absorption spectrum of the photopolymerization initiator (C) has a first absorption in the wavelength range of 350 nm to 370 nm and a second absorption in the wavelength range of 370 nm to 415 nm. Have. Therefore, when the coating film of the photosensitive resin composition is exposed to form a coating film, the photopolymerization initiator (C) can contribute to improve the deep-part curability of the coating film. In particular, it is preferable that the second absorption includes at least absorption in the wavelength range of 400 nm or more and 415 nm or less. In this case, when the coating film of the photosensitive resin composition is exposed to form a coating film, it can contribute to further improving the deep-part curability of the coating film. In the present embodiment, the absorption spectrum of the photopolymerization initiator (C) having “absorption” in a specific wavelength range means that the absorption spectrum of the photopolymerization initiator (C) is “photopolymerization initiator (C 2) the area under the curve in the specific wavelength range is 2% or more with respect to the area under the curve in the wavelength range of 350 nm or more and 370 nm or less. For example, the photopolymerization initiator (C) "absorbs light in the wavelength range of more than 370 nm and not more than 415 nm" means "above 350 nm of the photopolymerization initiator (C)" in the absorption spectrum of the photopolymerization initiator (C). The area under the curve in the wavelength range of more than 370 nm and less than 415 nm with respect to the curve area of the wavelength range of 370 nm or less is 2% or more. " The same applies to each wavelength range of the absorption spectrum of the photopolymerization initiator (C).

  It is also preferable that the photopolymerization initiator (C) further has a property of absorbing light having a wavelength of 305 nm or more and 325 nm or less. That is, it is preferable that the light absorption spectrum of the photopolymerization initiator (C) further has a third absorption within a wavelength range of 305 nm to 325 nm. In this case, when the coating film of the photosensitive resin composition is exposed to form a coating film, the curability of the coating film surface can be further improved. Of course, the light absorption spectrum of the photopolymerization initiator (C) may further have an absorption other than the above-mentioned first absorption, second absorption and third absorption. That is, the light absorption spectrum of the photopolymerization initiator (C) may have an absorption at a wavelength of less than 305 nm or an absorption at a wavelength of longer than 415 nm.

  The photopolymerization initiator (C) can contain an appropriate compound. In particular, the photopolymerization initiator (C) includes an acylphosphine oxide-based photopolymerization initiator (C1), an α-aminoalkylphenone-based photopolymerization initiator (C2), and an oxime ester-based photopolymerization initiator (C3). It is preferable to contain at least one selected from the group consisting of In this case, when the coating film of the photosensitive resin composition is exposed to form the coating film, the deep-part curability of the coating film can be further improved. Further, in this case, when the photosensitive resin composition is exposed to ultraviolet rays, high photosensitivity can be imparted to the photosensitive resin composition. Further, the occurrence of ion migration in the layer containing the cured product of the photosensitive resin composition is suppressed, and the insulation reliability of the layer can be further improved. In particular, the acylphosphine oxide-based photopolymerization initiator (C1) has a high photobleaching effect, a high deep-part curability, and can reduce discoloration of the coating film of the photosensitive resin composition. Further, the acylphosphine oxide photopolymerization initiator (C1) is unlikely to impair the electrical insulation of the cured product of the photosensitive resin composition. Therefore, by exposing and curing the photosensitive resin composition, a cured product having excellent electrical insulation is obtained, and this cured product is, for example, a solder resist layer, a plating resist layer, an etching resist layer, an interlayer insulating film. Suitable as a layer.

  Examples of the acylphosphine oxide photopolymerization initiator (C1) include monoacyl such as 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide and 2,4,6-trimethylbenzoyl-ethyl-phenyl-phosphinate. Phosphine oxide-based photopolymerization initiator, and bis- (2,6-dichlorobenzoyl) phenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, bis- (2 , 6-Dichlorobenzoyl) -4-propylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, bis- (2,6-dimethoxybenzoyl) phenylphosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,5-dimethylphenylphosphine oxide, bis- (2,4,6) -Trimethylbenzoyl) phenylphosphine oxide, (2,5,6-trimethylbenzoyl) -2,4,4-trimethylpentylphosphine oxide, and other bisacylphosphine oxide photoinitiators. Contains at least one ingredient. In particular, the acylphosphine oxide photopolymerization initiator (C1) preferably contains 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, and the acylphosphine oxide photopolymerization initiator (C1) is 2,4. It is also preferable to contain only 6,6-trimethylbenzoyl-diphenyl-phosphine oxide. In this case, higher deep-part curability can be imparted to the coating film formed from the photosensitive resin composition.

  Examples of the α-aminoalkylphenone photopolymerization initiator (C2) include 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one and 2-benzyl-2-dimethylamino-1-. Consists of (4-morpholinophenyl) -butanone-1 and 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone. It contains at least one component selected from the group. The α-aminoacetophenone photopolymerization initiator (C2) can impart higher depth curability to the coating film formed from the photosensitive resin composition.

  Examples of the oxime ester photopolymerization initiator (C3) include 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)], and ethanone, 1- [9-ethyl- It can contain at least one component selected from the group consisting of 6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime). As a more specific example of a component that can be contained in the oxime ester photopolymerization initiator (C3), BASF Corporation, product numbers Irgacure OXE 01, Irgacure OXE 02, and ADEKA Corporation ADEKA ACTOMER N-1919, ADEKA ARC. Ruze NCI-831, and ADEKA ARCRUZ NCI-930.

  The light absorption spectrum of the oxime ester photopolymerization initiator (C1) preferably has absorption in a wavelength range longer than 350 nm. In this case, since the deep-part curability of the coating film formed from the photosensitive resin composition can be enhanced, the sensitivity of the coating film can be increased. Therefore, the photosensitive resin composition is particularly suitable for applications such as a solder resist layer, a plating resist layer, an etching resist layer, and an interlayer insulating layer.

  The photopolymerization initiator (C) preferably contains a hydrogen abstraction type photopolymerization initiator (C4). In this case, when the coating film formed from the photosensitive resin composition is exposed and then developed to produce a coating film, the shape of the coating film has higher resolution. In this case, the shape of the holes can be made sharper when the film having the holes is produced by exposing and then developing.

  The hydrogen abstraction type photopolymerization initiator (C4) contains, for example, at least one component selected from the group consisting of bis (dialkylamino) benzophenone photopolymerization initiator (C41) and thioxanthone photopolymerization initiator (C42). Including.

  The bis (dialkylamino) benzophenone-based photopolymerization initiator (C41) is selected from the group consisting of 4,4′-bis (diethylamino) benzophenone (EAB) and 4,4′-bis (dimethylamino) benzophenone, for example. It contains at least one component. Particularly, the bis (dialkylamino) benzophenone photopolymerization initiator (C41) preferably contains 4,4′-bis (diethylamino) benzophenone. In this case, the resolution is particularly high when the coating film formed from the photosensitive resin composition is partially exposed and then developed. Therefore, it becomes possible to form a very fine pattern with the cured product of the photosensitive resin composition. In particular, when an interlayer insulating layer of a multilayer printed wiring board is prepared from a photosensitive resin composition and a small diameter hole for a through hole is formed in this interlayer insulating layer by photolithography, a small diameter hole can be formed accurately and easily. It becomes possible to do.

  The thioxanthone photopolymerization initiator (C42) is at least one selected from the group consisting of thioxanthones such as 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, and 2,4-diisopropylthioxanthone. Contains ingredients.

  The photopolymerization initiator (C) may contain a hydroxyketone-based photopolymerization initiator. The hydroxyketone-based photopolymerization initiator is, for example, 1-hydroxy-cyclohexyl-phenyl-ketone, phenylglyoxic acid methyl ester, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl. -1-propan-1-one, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one and 2- It contains at least one compound selected from the group consisting of hydroxy-2-methyl-1-phenyl-propan-1-one.

  The photopolymerization initiator (C) may contain only one kind of the components that can be contained in the photopolymerization initiator (C) described above, or may contain two or more kinds of components. When the photopolymerization initiator (C) contains two or more components, the above-mentioned light absorption characteristics of the photopolymerization initiator (C) in the present embodiment may be achieved by a combination of two or more components. ..

  The amount of the acylphosphine-based photopolymerization initiator (C1) based on the total amount of the photopolymerization initiator (C) is preferably 20% by mass or more and 100% by mass or less, and 50% by mass or more and 95% by mass or less. More preferable. The amount of the α-aminoalkylphenone-based photopolymerization initiator (C2) based on the total amount of the photopolymerization initiator (C) is preferably 20% by mass or more and 100% by mass or less, and 50% by mass or more and 95% by mass or less. Is more preferable. The amount of the oxime ester-based photopolymerization initiator (C3) based on the total amount of the photopolymerization initiator (C) is preferably 1% by mass or more and 100% by mass or less, and more preferably 5% by mass or more and 40% by mass or less. preferable. The amount of the hydrogen abstraction type photopolymerization initiator (C4) based on the total amount of the photopolymerization initiator (C) is preferably 1% by mass or more and 60% by mass or less, and 1% by mass or more and 30% by mass or less. Is more preferable and 1% by mass or more and 5% by mass or less is further preferable.

  The photosensitive resin composition may further contain a photopolymerization accelerator, a sensitizer and the like without departing from the spirit of the present invention. For example, the photosensitive resin composition includes benzoin and its alkyl ethers; acetophenones such as acetophenone and benzyldimethylketal; anthraquinones such as 2-methylanthraquinone; benzophenones such as benzophenone and 4-benzoyl-4′-methyldiphenyl sulfide. And at least one component selected from the group consisting of xanthones such as 2,4-diisopropylxanthone. The photosensitive resin composition, together with the photopolymerization initiator (C), photopolymerization of tertiary amines such as p-dimethylbenzoic acid ethyl ester, p-dimethylaminobenzoic acid isoamyl ester and 2-dimethylaminoethylbenzoate. You may contain a promoter, a sensitizer, etc.

  The epoxy resin (D) can impart thermosetting property to the photosensitive resin composition. The epoxy resin (D) preferably contains a crystalline epoxy resin (D1). In this case, the developability of the photosensitive resin composition can be improved. Furthermore, since the organic filler (E1) has a carboxyl group, the compatibility of the crystalline epoxy resin (D1) is improved with the organic filler (E1), and the crystalline epoxy resin (D1) in the photosensitive resin composition is recrystallized. Can be prevented. Moreover, the epoxy resin (D) may further contain an amorphous epoxy resin (D2). Here, the "crystalline epoxy resin" is an epoxy resin having a melting point, and the "amorphous epoxy resin" is an epoxy resin having no melting point.

  The crystalline epoxy resin (D1) is, for example, 1,3,5-tris (2,3-epoxypropyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, Hydroquinone type crystalline epoxy resin (specific example: Nippon Steel & Sumikin Chemical Co., Ltd., product name YDC-1312), biphenyl type crystalline epoxy resin (Mitsubishi Chemical Co., Ltd., product name YX-4000), diphenyl ether type crystal epoxy Resin (specific example, product number YSLV-80DE manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), bisphenol type crystalline epoxy resin (specific example, product name YSLV-80XY manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), tetrakisphenolethane type crystalline epoxy resin ( As a specific example, it is preferable to contain one or more components selected from the group consisting of Nippon Kayaku Co., Ltd. product number GTR-1800) and a bisphenolfluorene type crystalline epoxy resin.

  The crystalline epoxy resin (D1) preferably has two epoxy groups in one molecule. In this case, it is possible to further prevent the cured product from cracking during repeated temperature changes.

  The crystalline epoxy resin (D1) preferably has an epoxy equivalent of 150 g / eq or more and 300 g / eq or less. The epoxy equivalent weight is the gram weight of the crystalline epoxy resin (D1) containing 1 gram equivalent of epoxy groups. The crystalline epoxy resin (D1) has a melting point. The melting point of the crystalline epoxy resin (D1) is, for example, 70 ° C. or higher and 180 ° C. or lower.

  In particular, the epoxy resin (D) preferably contains a crystalline epoxy resin (D1-1) having a melting point of 110 ° C. or lower. In this case, the developability of the photosensitive resin composition with an alkaline aqueous solution is particularly improved. The crystalline epoxy resin (D1-1) having a melting point of 110 ° C. or lower is, for example, a biphenyl type epoxy resin (specific example, product number YX-4000 manufactured by Mitsubishi Chemical Corporation), a biphenyl ether type epoxy resin (specific example, Nippon Steel & Sumikin Chemical Co., Ltd.). It can contain at least one component selected from the group consisting of company product number YSLV-80DE), bisphenol type epoxy resin (specific example, product number YSLV-80XY manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), and bisphenolfluorene type crystalline epoxy resin. ..

  The amorphous epoxy resin (D2) is, for example, phenol novolac type epoxy resin (specific example, product number EPICLON N-775 manufactured by DIC Corporation), cresol novolac type epoxy resin (specific example, product number EPICLON N manufactured by DIC Corporation). -695), bisphenol A novolac type epoxy resin (specific example, product number EPICLON N-865 manufactured by DIC Corporation), bisphenol A type epoxy resin (specific example, product number jER1001 manufactured by Mitsubishi Chemical Corporation), bisphenol F type epoxy resin. (Specific example: product number jER4004P manufactured by Mitsubishi Chemical Co., Ltd.), bisphenol S type epoxy resin (specific example: product number EPICLONEXA-1514 manufactured by DIC Corporation), bisphenol AD type epoxy resin, biphenyl novolac type epoxy resin (specific example Japan. Kayaku Co., Ltd. product number NC-3000), hydrogenated bisphenol A type epoxy resin (specific example, Nippon Steel & Sumikin Chemical Co., Ltd. product number ST-4000D), naphthalene type epoxy resin (specific example, DIC product number EPICLON HP-4032, EPICLON HP-4700, EPICLON HP-4770), tertiary butyl catechol type epoxy resin (specific example DIC Corporation make part number EPICLON HP-820), dicyclopentadiene type epoxy resin (specific example DIC) Manufactured by EPICLON HP-7200), adamantane type epoxy resin (as a specific example, product number ADAMANTATEX-E-201 manufactured by Idemitsu Kosan Co., Ltd.), special bifunctional epoxy resin (as a specific example, product number YL7175 manufactured by Mitsubishi Chemical Corporation). -500, and YL7175-1000; Part numbers EPICLON TSR-960, EPICLON TER-601, EPICLON TSR-250-80BX, EPICLON 1650-75MPX, EPICLON EXA-4850, EPICLON EXA-4816, EPICLON EX manufactured by DIC Corporation. , And EPICLON EXA-9726; product number YSLV-120TE manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., rubber-like core shell polymer modified bisphenol A type epoxy resin (specifically, product number MX-156 manufactured by Kaneka Co., Ltd.), rubber-like core shell polymer modified. Bisphenol F type epoxy resin Kaneka product number MX-136), and rubber particle-containing bisphenol F type epoxy resin (specific example Kaneka product number Kaneace MX-130) selected from the group consisting of components. preferable.

  The epoxy resin (D) may contain a phosphorus-containing epoxy resin. In this case, the flame retardancy of the cured product of the photosensitive resin composition is improved. The phosphorus-containing epoxy resin may be contained in the crystalline epoxy resin (D1) or the amorphous epoxy resin (D2). The phosphorus-containing epoxy resin is, for example, a phosphoric acid-modified bisphenol F type epoxy resin (as specific examples, product numbers EPICLON EXA-9726 and EPICLON EXA-9710 manufactured by DIC Corporation), product number Epototo FX-305 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. Etc.

  The epoxy compound (D) may contain an epoxy compound (D3) having a bisphenolfluorene skeleton. The epoxy compound (D3) includes, for example, the epoxy compound (a1) having the bisphenolfluorene skeleton (S1) represented by the formula (1) described above.

  The photosensitive resin composition preferably contains a colorant (E). In this case, when forming a film from the photosensitive resin composition, when the coating film of the photosensitive resin composition is exposed, scattering in the coating film can be suppressed. For this reason, it is possible to make it more difficult to reduce the resolution due to light scattering. Thereby, when a coating film formed from the photosensitive resin composition is exposed and then developed to produce a coating film, the shape of the coating film may have higher resolution. In this case, the shape of the holes can be made sharper when the film having the holes is produced.

  The colorant (E) is a substance capable of coloring a film formed from the photosensitive resin composition, for example. The colorant can include both pigments and dyes. When the photosensitive resin composition contains a colorant, the colorant may contain any of a pigment, a dye and a pigment. The colorant (E) can contain, for example, one or more materials selected from the group consisting of a black colorant, a blue colorant, and a yellow colorant.

  Examples of black colorants include carbon black, naphthalene black, titanium black, lactam black and perylene black.

  Examples of blue colorants include phthalocyanine compounds and anthraquinone compounds.

  Examples of yellow colorants include monoazo compounds, disazo compounds, condensed azo compounds, benzimidazolone compounds, isoindolinone compounds, and anthraquinone compounds.

  The colorant (E) may be a colorant having a color other than the above. Examples of colorants having colors other than the above include at least one component selected from the group consisting of red colorants, green colorants, purple colorants, orange colorants, and brown colorants.

  Examples of red colorants include monoazo compounds, disazo compounds, azo lake compounds, benzimidazolone compounds, perylene compounds, diketopyrrolopyrrole compounds, condensed azo compounds, anthraquinone compounds, and quinacridone compounds. Including.

  Examples of green colorants include phthalocyanine compounds, anthraquinone compounds, and perylene compounds.

  The photosensitive resin composition preferably contains a component having a bisphenolfluorene skeleton. In this case, the component having a bisphenolfluorene skeleton can absorb light in the wavelength range of 305 nm to 325 nm due to the bisphenolfluorene skeleton. For this reason, it is possible to prevent the scattering of light at the time of exposure to occur particularly easily, and to prevent the deterioration of resolution from occurring more easily. The component having a bisphenolfluorene skeleton is, for example, from the group consisting of the carboxyl group-containing resin (A1) having the bisphenolfluorene skeleton, the unsaturated compound (B1) having the bisphenolfluorene skeleton, and the epoxy compound (D3) having the bisphenolfluorene skeleton. It contains at least one compound selected.

  The amounts of the components in the photosensitive resin composition are appropriately adjusted so that the photosensitive resin composition has photocurability and can be developed with an alkaline solution.

  The amount of the carboxyl group-containing resin (A) is preferably 5% by mass or more and 85% by mass or less, more preferably 10% by mass or more and 75% by mass or less, and more preferably 20% by mass or less with respect to the solid content of the photosensitive resin composition. More preferably, it is from 60% by mass to 60% by mass.

  The amount of the unsaturated compound (B) is preferably 1% by mass or more and 50% by mass or less with respect to the carboxyl group-containing resin (A), more preferably 10% by mass or more and 45% by mass or less, and 15% by mass. More preferably, it is 40% by mass or less.

  The amount of the photopolymerization initiator (C) is preferably 0.1% by mass or more and 30% by mass or less, more preferably 1% by mass or more and 25% by mass or less, based on the carboxyl group-containing resin (A). More preferably, it is 3% by mass or more and 20% by mass or less.

  Regarding the amount of the epoxy resin (D), the total of the equivalents of the epoxy groups contained in the epoxy resin (D) is 0.7 or more and 2.5 with respect to 1 equivalent of the carboxyl group contained in the carboxyl group-containing resin (A). It is preferably the following or less, more preferably 0.7 or more and 2.3 or less, and further preferably 0.7 or more and 2.0 or less.

  When the photosensitive resin composition contains the colorant (E), the amount of the colorant (E) is preferably 0.1% by mass or more and 15% by mass or less based on the carboxyl group-containing resin (A), It is more preferable if it is 0.5% by mass or more and 10% by mass or less.

  When the photosensitive resin composition contains a component having a bisphenolfluorene skeleton, the amount of the component having a bisphenolfluorene skeleton is 10% by mass or more and 70% by mass or less based on the solid content of the photosensitive resin composition. It is more preferably 20% by mass or more and 60% by mass or less.

  When the photosensitive resin composition contains an organic solvent, the amount of the organic solvent is such that the organic solvent is volatilized quickly when the coating film formed from the photosensitive resin composition is dried, that is, the organic solvent is dried. It is preferably adjusted so that it does not remain in the film. In particular, the organic solvent is preferably more than 0 mass% and 99.5 mass% or less, and more preferably 15 mass% or more and 60 mass% or less with respect to the entire photosensitive resin composition. Since a suitable ratio of the organic solvent varies depending on the coating method and the like, it is preferable to appropriately adjust the ratio according to the coating method.

  The solid content is the total amount of all components excluding volatile components such as a solvent from the photosensitive resin composition.

  The photosensitive resin composition may further contain components other than the above components without departing from the gist of the present invention.

  For example, the photosensitive resin composition may contain an inorganic filler. In this case, curing shrinkage when curing the coating film formed from the photosensitive resin composition is reduced. The inorganic filler is, for example, at least one material selected from the group consisting of barium sulfate, crystalline silica, nanosilica, carbon nanotubes, talc, bentonite, hydrotalcite, aluminum hydroxide, magnesium hydroxide, zinc oxide and titanium oxide. Can be included. The proportion of the inorganic filler in the photosensitive resin composition is appropriately set, but is preferably 0% by mass or more and 200% by mass or less, and 0% by mass or more and 100% by mass or less with respect to the carboxyl group-containing resin (A). Is more preferable, and 0% by mass or more and 50% by mass or less is further preferable.

  The photosensitive resin composition is a blocked diisocyanate, morpholine diisocyanate, isophorone diisocyanate or hexamethylene diisocyanate blocked isocyanate blocked with caprolactam, oxime, malonic acid ester or the like; melamine resin, n-butylated melamine resin. , Amino resins such as isobutylated melamine resin, butylated urea resin, butylated melamine urea co-condensed resin, and benzoguanamine co-condensed resin; various thermosetting resins other than the above; UV curable epoxy (meth) acrylate; bisphenol A type , Phenol novolac type, cresol novolac type, alicyclic type and other resins obtained by adding (meth) acrylic acid to epoxy resin; and polymer compounds such as diallyl phthalate resin, phenoxy resin, urethane resin and fluororesin It may contain at least one resin selected from the group.

  The photosensitive resin composition may contain a curing agent for curing the epoxy resin (D). The curing agent is, for example, imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1- (2 -Cyanoethyl) -2-ethyl-4-methylimidazole and other imidazole derivatives; dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N-dimethylbenzylamine, Amine compounds such as 4-methyl-N, N-dimethylbenzylamine; hydrazine compounds such as adipic acid hydrazide and sebacic acid hydrazide; phosphorus compounds such as triphenylphosphine; acid anhydrides; phenols; mercaptans; Lewis acid amine complexes; And at least one component selected from the group consisting of onium salts. Examples of commercially available products of these components include 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, 2P4MHZ (both are trade names of imidazole compounds) manufactured by Shikoku Kasei Co., Ltd., U-CAT3503N, U manufactured by San-Apro Co., Ltd. -CAT3502T (all are brand names of the block isocyanate compound of dimethylamine), DBU, DBN, U-CATSA102, U-CAT5002 (all are a bicyclic amidine compound and its salt).

  The photosensitive resin composition may contain an adhesion promoter. Examples of the adhesion-imparting agent include melamine, guanamine, acetoguanamine, benzoguanamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-4,6-diamino-S-triazine and 2- Examples thereof include S-triazine derivatives such as vinyl-4,6-diamino-S-triazine / isocyanuric acid adduct and 2,4-diamino-6-methacryloyloxyethyl-S-triazine / isocyanuric acid adduct.

  The photosensitive resin composition is a curing accelerator; a copolymer such as silicone or acrylate; a leveling agent; an adhesion promoter such as a silane coupling agent; a thixotropic agent; a polymerization inhibitor; an antihalation agent; a flame retardant; a defoaming agent. It may contain at least one component selected from the group consisting of an agent; an antioxidant; a surfactant; and a polymer dispersant.

  The content of the amine compound in the photosensitive resin composition is preferably as low as possible. In this case, the electrical insulation of the layer made of the cured product of the photosensitive resin composition is not easily impaired. In particular, the amine compound content is preferably 6% by mass or less, more preferably 4% by mass or less, based on the carboxyl group-containing resin (A).

  The photosensitive resin composition can be prepared by blending the raw materials of the photosensitive resin composition as described above and kneading them by a kneading method using, for example, a three-roll, ball mill, sand mill or the like. When the raw material of the photosensitive resin composition contains a liquid component, a low-viscosity component, etc., a part of the raw material excluding the liquid component, the low-viscosity component, etc. is first kneaded, and the resulting mixture is The photosensitive resin composition may be prepared by adding and mixing a liquid component, a component having a low viscosity, and the like.

  In consideration of storage stability and the like, the first agent may be prepared by mixing a part of the components of the photosensitive resin composition, and the second agent may be prepared by mixing the rest of the components. That is, the photosensitive resin composition may include a first agent and a second agent. In this case, for example, the first compound is prepared by previously mixing and dispersing the unsaturated compound (B), a part of the organic solvent, and the thermosetting component among the components of the photosensitive resin composition to prepare the photosensitive resin. The second agent may be prepared by mixing and dispersing the rest of the components of the composition. In this case, a required amount of the first agent and the second agent may be appropriately mixed to prepare a mixed solution, and the mixed solution may be cured to obtain a cured product.

  The photosensitive resin composition according to the present embodiment is suitable as an electrically insulating material for printed wiring boards. Particularly, the photosensitive resin composition is suitable for forming an electrically insulating layer such as a solder resist layer, a plating resist layer, an etching resist layer, and an interlayer insulating layer.

  When the photosensitive resin composition is formed into a film having a thickness of 25 μm, the film is preferably developable with an aqueous sodium carbonate solution. In this case, since a sufficiently thick electrically insulating layer can be produced from the photosensitive resin composition by the photolithography method, the photosensitive resin composition is used as an interlayer insulating layer in a printed wiring board or a solder resist. It is widely applicable for making layers and the like. Of course, it is also possible to form an electrically insulating layer thinner than 25 μm from the photosensitive resin composition.

The fact that the film can be developed with an aqueous sodium carbonate solution can be confirmed by the following method. The photosensitive resin composition is applied onto an appropriate substrate to form a wet coating film, and the wet coating film is heated at 80 ° C. for 40 minutes to form a film having a thickness of 25 μm. With a negative mask having an exposed portion that transmits ultraviolet rays and a non-exposed portion that blocks ultraviolet rays applied directly to this coating, the coating is irradiated with ultraviolet rays at 500 mJ / cm ² through the negative mask. The exposed film is sprayed with a 1% Na ₂ CO ₃ aqueous solution at 30 ° C. at a spray pressure of 0.2 MPa for 90 seconds, and then pure water is sprayed at a spray pressure of 0.2 MPa for 90 seconds. As a result of observing the film after this treatment, when the part corresponding to the non-exposed part in the film is removed and no residue is observed, it can be determined that the film can be developed.

  As described above, the method for producing a coating film according to the present embodiment includes a step of forming a coating film on a substrate by arranging the coating film of the photosensitive resin composition on the substrate, and applying a light to the coating film. And a step of exposing the coating film after exposure with an alkaline solution. Hereinafter, a method for producing a film formed from the photosensitive resin composition of the present embodiment and a method for producing a printed wiring board having the film will be described in detail with reference to FIG.

  To form a coating film of the photosensitive resin composition on the base material, first, as shown in FIG. 3A, the core material 1 is prepared as the base material. The core material 1 includes, for example, at least one insulating layer 2 and at least one conductive layer 3. The conductive layer 3 may be a conductor wiring. The conductive layer 3 provided on one surface of the core material 1 is hereinafter referred to as a first conductor wiring 31. As shown in FIG. 3B, a coating film 4 made of a photosensitive resin composition is formed on the surface of the core material 1 on which the first conductor wiring 31 is provided. The coating film 4 can be formed from the photosensitive resin composition by a method such as a coating method and a dry film method.

  In the coating method, for example, the photosensitive resin composition is coated on a base material such as the core material 1 to form a wet coating film. The method for applying the photosensitive resin composition is selected from the group consisting of, for example, a dipping method, a spray method, a spin coating method, a roll coating method, a curtain coating method, and a screen printing method. Subsequently, in order to volatilize the organic solvent in the photosensitive resin composition, the wet coating film may be dried, for example, at a temperature in the range of 60 to 120 ° C. to obtain coating film 4 (dry coating film). it can.

  In the dry film method, first, a photosensitive resin composition is applied onto an appropriate support such as polyester and then dried to form a dry film containing the photosensitive resin composition on the support. Thereby, a dry film with a support including a dry film and a support that supports the dry film can be obtained. The dry film in the dry film with a support is superposed on the core material 1, pressure is applied to the dry film and the core material 1, and then the support is peeled off from the dry film. Transfer to the material 1. As a result, the coating film 4 made of a dry film is provided on the core material 1.

  In this way, the coating film 4 of the photosensitive resin composition can be arranged on the base material such as the core material 1 to form the coating film 4 on the base material.

  In the light absorption spectrum of the coating film 4 of the present embodiment, the maximum absorbance of light in the wavelength range of 305 nm to 325 nm is preferably 3 times or more the maximum absorbance of the wavelength range of 350 nm to 370 nm. In this case, when exposing the coating film formed from the photosensitive resin composition, light scattering in the coating film can be suppressed. For this reason, it is possible to make it more difficult to reduce the resolution due to light scattering. Thereby, when a coating film formed from the photosensitive resin composition is exposed and then developed to produce a coating film, the shape of the coating film may have higher resolution. In this case, for example, when forming a film having pores from the photosensitive resin composition by the photolithography method, the shape of the pores can be made sharper. The absorption spectrum of the coating film is measured by a spectroscopic analyzer such as a spectrophotometer. The specific measuring method can be measured in the same manner as in the evaluation test (4-1) of the examples described later.

  Next, the coating film 4 formed on the core material 1 is irradiated with light to expose the coating film 4. In exposing the coating film 4, for example, light emitted from a light source can be applied to the coating film 4. In the present embodiment, as described above, the spectrum of the light with which the coating film is irradiated in the exposure step has the first intensity distribution at the wavelength overlapping the wavelength of the first absorption within the wavelength range of 350 nm to 370 nm. And a second intensity distribution having a wavelength overlapping the wavelength of the second absorption within a wavelength range of more than 370 nm and not more than 415 nm, and a third intensity distribution having a wavelength range of not less than 305 nm and not more than 325 nm. Further, in the spectrum of this light, the sum of the area under the curve in the wavelength range from 280 nm to 200 nm and the area under the curve in the wavelength range from 415 nm to 500 nm is calculated with respect to the area under the curve in the wavelength range from 200 nm to 500 nm. The percentage is 5% or less.

  The light source is preferably at least one selected from the group consisting of a metal halide lamp, a high pressure mercury lamp, and an ultrahigh pressure mercury lamp. In this case, a high resolution image can be formed with a short exposure time.

  In the present embodiment, in the exposing step, the light emitted from the light source is passed through an optical filter that cuts light in the wavelength range shorter than 280 nm and 200 nm or more and light in the wavelength range longer than 415 nm and 500 nm or less. It is preferable to irradiate the coating film. In this case, the area under the curve in the wavelength range from 280 nm to 200 nm and the curve in the wavelength range from 415 nm to 500 nm with respect to the area under the curve in the wavelength range from 200 nm to 500 nm in the spectrum of the light with which the coating film is irradiated. The total percentage with the lower area can be 5% or less.

  The coating film may be irradiated with light emitted from a light source other than the metal halide lamp, the high-pressure mercury lamp, and the extra-high pressure mercury lamp without departing from the gist of the present invention.

  As the optical filter, an appropriate filter that cuts light in a predetermined wavelength range can be adopted. An example of the optical filter is, for example, a bandpass filter that transmits only light in a specific wavelength range and cuts other short-wavelength side light and longer-wavelength side light. As long as the optical filter has the above-mentioned action, a long-pass filter and a short-pass filter, or a combination of two or more thereof, is used for light in a specific wavelength range (for example, light having a wavelength shorter than 280 nm and light having a wavelength of 415 nm or less). Only light other than light having a long wavelength) may be transmitted. Further, the size, shape, arrangement method, etc. of the optical filter are not particularly limited. For example, the optical filter should just be arrange | positioned in the position between the coating film 4 and a light source.

  By exposing the coating film 4, the coating film 4 is partially photocured as shown in FIG. 3C. For example, after applying a negative mask to the coating film 4, the coating film 4 is irradiated with light through the negative mask. The negative mask includes an exposed portion that transmits light and a non-exposed portion that shields the light. The non-exposed portion is provided at a position that matches the position of the through hole 10. The negative mask is a photo tool such as a mask film or a dry plate.

  In exposing, a method other than the method using the negative mask may be adopted. For example, the coating film 4 may be exposed by a direct drawing method in which light emitted from a light source is applied only to the portion of the coating film 4 to be exposed. The light source applied to the direct drawing method is selected from the group consisting of, for example, a laser, an LED (Light Emitting Diode), a high pressure mercury lamp, an ultrahigh pressure mercury lamp, and a metal halide lamp.

  In the dry film method, the dry film in the dry film with the support is superposed on the core material 1, and then the support is transmitted and the coating film 4 made of the dry film is irradiated with ultraviolet rays without separating the support. Thus, the support may be peeled off from the coating film 4 after the exposure, and subsequently, before the development treatment.

  Subsequently, the exposed coating film 4 is subjected to a development treatment to remove the unexposed portion (non-exposed portion) 5 of the coating film 4 shown in FIG. 3C. Thereby, as shown in FIG. 3D, the holes 6 are provided in the film 40 at the positions where the through holes 10 are formed.

  In the development processing, an appropriate developing solution can be used according to the composition of the photosensitive resin composition. The developer is, for example, an alkaline aqueous solution containing at least one of an alkali metal salt and an alkali metal hydroxide, or an organic amine. More specifically, the alkaline aqueous solution is, for example, sodium carbonate, potassium carbonate, ammonium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, ammonium hydrogen carbonate, sodium hydroxide, potassium hydroxide, ammonium hydroxide, tetramethylammonium hydroxide or It contains at least one component selected from the group consisting of lithium hydroxide. The solvent in the alkaline aqueous solution may be only water or a mixture of water and a hydrophilic organic solvent such as lower alcohols. The organic amine contains, for example, at least one component selected from the group consisting of monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine and triisopropanolamine.

  The developer is preferably an alkaline aqueous solution containing at least one of an alkali metal salt and an alkali metal hydroxide, and particularly preferably an aqueous sodium carbonate solution. In this case, it is possible to improve the working environment and reduce the burden of waste treatment.

  Thereby, the film 40 containing the photosensitive resin composition can be formed on the substrate. The shape of the coating film 40 containing the photosensitive resin composition thus produced may have high resolution. Further, in this case, the shape of the holes formed in the film 40 can be made sharper.

  The coating 40 produced above may be further treated as follows.

  For example, you may heat-harden the film 40 by heating. The heating conditions are, for example, a heating temperature of 120 to 200 ° C. and a heating time of 30 to 120 minutes. In this case, performances such as strength, hardness, and chemical resistance of the interlayer insulating layer 7 formed from the film 40 are improved. If necessary, the coating film 40 may be further irradiated with ultraviolet light before or after heating or both. In this case, the photo-curing of the film 40 can be further advanced.

  Thereby, the interlayer insulating layer 7 including the film 40 of the photosensitive resin composition (also referred to as a cured product of the photosensitive resin composition) is provided on the base material such as the core material 1.

  Further, the coating 40 (interlayer insulating layer 7) may be plated. An appropriate method can be adopted for the plating treatment. For example, the second conductor wiring 8 and the hole plating 9 can be provided on the interlayer insulating layer 7 by a method such as an additive method. As a result, as shown in FIG. 3E, the first conductor wiring 31, the second conductor wiring 8, the interlayer insulating layer 7 interposed between the first conductor wiring 31 and the second conductor wiring 8, and the first conductor wiring 31 and the second conductor wiring 8 are formed. A printed wiring board 11 having a through hole 10 for electrically connecting the one conductor wiring 31 and the second conductor wiring 8 is obtained. Note that, in FIG. 3E, the hole plating 9 has a cylindrical shape that covers the inner surface of the hole 6, but the entire inside of the hole 6 may be filled with the hole plating 9. When the hole plating 9 is provided, a part of a roughened outer surface, which will be described later, and an inner side surface of the hole 6 may be subjected to electroless metal plating treatment to form an initial wiring. After that, the hole plating 9 can be formed by depositing the metal in the electrolyte plating solution on the initial wiring by electrolytic metal plating treatment.

  Further, the surface of the film 40 may be roughened by performing a roughening process on the film 40 before performing the plating process. For example, in roughening a part of the outer surface of the interlayer insulating layer 7 and the entire inner surface of the hole 6, the same procedure as a general desmear process using an oxidizing agent can be performed. For example, an oxidizing agent is brought into contact with the outer surface of the interlayer insulating layer 7 to give the interlayer insulating layer 7 a rough surface. However, the present invention is not limited to this, and a method of imparting a rough surface to a cured product such as plasma treatment, UV treatment or ozone treatment can be appropriately adopted. The oxidant may be an oxidant available as a Desmear solution. For example, an oxidant can be composed of a commercially available swelling liquid for desmear and a desmear liquid. Such an oxidizing agent can contain, for example, at least one permanganate selected from the group of sodium permanganate and potassium permanganate.

  An example of a method for manufacturing a printed wiring board including a solder resist layer formed of the photosensitive resin composition according to the present embodiment will be described.

  First, a core material as a base material is prepared. The core material includes, for example, at least one insulating layer and at least one conductor wiring (conductive layer). A coating film is formed from the photosensitive resin composition on the surface of the core material on which the conductor wiring is provided. Examples of the method for forming a coating film include a coating method and a dry film method. As the coating method and the dry film method, the same methods as those for forming a coating film on the above-mentioned substrate can be adopted. The coating film is exposed to partially photo-cure it. As the exposure method, the same method as in the case of forming the interlayer insulating layer can be adopted. Subsequently, the coating film is subjected to a development treatment to remove the unexposed portion of the coating film, whereby the exposed portion of the coating film remains on the core material. Then, the coating formed on the core material is heated to be thermoset. As the developing method and the heating method, the same methods as those for forming the above-described interlayer insulating layer can be adopted. If necessary, the coating may be further irradiated with ultraviolet light before or after heating, or both. In this case, the photo-curing of the film can be further advanced.

  As described above, the solder resist layer made of the cured product of the photosensitive resin composition is provided on the core material. As a result, a printed wiring board including a core material including an insulating layer and a conductor wiring (conductive layer) thereon and a solder resist layer that partially covers a surface of the core material on which the conductor wiring is provided is obtained. .

  Hereinafter, specific examples of the present invention will be presented. However, the present invention is not limited to the examples.

(1) Synthesis of Resin Containing Carboxyl Group (1-1) Synthesis Example A-1 and Synthesis Example B-1
A four-necked flask equipped with a reflux condenser, a thermometer, an air blowing tube, and a stirrer was charged with the components shown in the "first reaction" column in Table 1 and stirred under air bubbling to form a mixture. Was prepared. The mixture was heated in the flask while stirring under air bubbling, at the reaction temperature and reaction time shown in the "reaction conditions" column. Thereby, a solution of the intermediate was prepared.

  Then, the components shown in the "second reaction" column of Table 1 were added to the solution of the intermediate in the flask, and the reaction temperature and reaction time shown in the "reaction condition (1)" column were added while stirring under air bubbling. Heated. Subsequently, in Synthesis Example A-1, heating was performed at a reaction temperature and a reaction time shown in the "reaction conditions (2)" column while stirring under air bubbling. As a result, a 65 mass% solution of the carboxyl group-containing resin was obtained. The polydispersity of the carboxyl group-containing resin (excluding the carboxyl group-containing resin of Synthesis Example B-1), the weight average molecular weight, and the acid value are as shown in Table 1. The molar ratio between the components is also shown in Table 1.

The details of the components shown in column (a1) of Table 1 are as follows.
Epoxy compound 1: a bisphenolfluorene type epoxy compound represented by the formula (7) and having an epoxy equivalent of 250 g / eq, in which R _{1 to} R ₈ in the formula (7) are all hydrogen.

The details of the components shown in column (g1) of Table 1 are as follows.
Epoxy compound 2: Cresol novolac type epoxy resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., product number YDC-700-5, epoxy equivalent 203 g / eq).

(2) Preparation of photosensitive resin composition (Examples 1 to 9)
A part of the components shown in the table below was kneaded with a three-roll, and then all the components shown in the table below were stirred and mixed in a flask to obtain a photosensitive resin composition. The details of the components shown in the table are as follows. Further, in the following photopolymerization initiator, "does not absorb light" for a specific wavelength means that in the absorption spectrum of the photopolymerization initiator, "the area under the curve in the wavelength range of 350 nm to 370 nm of the photopolymerization initiator The area under the curve in each wavelength range is less than 2%. For example, the photopolymerization initiator B "does not absorb light having a wavelength of 400 nm or more and 415 nm or less" means that "in the wavelength range of 350 nm or more and 370 nm or less of the photopolymerization initiator B" in the absorption spectrum of the photopolymerization initiator B. The area under the curve in the wavelength range of 400 nm or more and 415 nm or less with respect to the area under the curve is less than 2% ”.
-Unsaturated compound A: trimethylolpropane triacrylate.
-Unsaturated compound B: A mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., product number KAYARAD DPHA).
-Photopolymerization initiator A: 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (manufactured by BASF, product number Irgacure TPO); acylphosphine oxide-based photopolymerization initiator. It has a property of absorbing light having a wavelength of 305 nm to 325 nm, light having a wavelength of 350 nm to 370 nm, light having a wavelength longer than 370 nm and less than 400 nm, and light having a wavelength of 400 nm to 415 nm.
Photopolymerization initiator B: 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one (manufactured by BASF, product number Irgacure 907); α-aminoalkylphenone photopolymerization initiator. It has a characteristic of absorbing light having a wavelength of 305 nm or more and 325 nm or less, light having a wavelength of 350 nm or more and 370 nm or less, and light having a wavelength longer than 370 nm and shorter than 400 nm. It does not absorb light having a wavelength of 400 nm or more and 415 nm or less.
-Photopolymerization initiator C: ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime) (manufactured by BASF, product number Irgacure) OXE 02); oxime ester-based photopolymerization initiator. It has a characteristic of absorbing light having a wavelength of 305 nm or more and 325 nm or less, light having a wavelength of 350 nm or more and 370 nm or less, and light having a wavelength longer than 370 nm and shorter than 400 nm. It does not absorb light having a wavelength of 400 nm or more and 415 nm or less.
Photopolymerization initiator D: 1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by BASF, product number Irgacure 184); α-hydroxyalkylphenone photopolymerization initiator. It has a characteristic of absorbing light having a wavelength of 305 nm or more and 325 nm or less, light having a wavelength of 350 nm or more and 370 nm or less, and light having a wavelength longer than 370 nm and shorter than 400 nm. It does not absorb light having a wavelength of 400 nm or more and 415 nm or less.
-Photopolymerization initiator E: 2,4-diethylthioxanthone (manufactured by Nippon Kayaku Co., Ltd., product number KAYACURE-DETX-S); hydrogen abstraction type photopolymerization initiator. It has a property of absorbing light having a wavelength of 305 nm to 325 nm, light having a wavelength of 350 nm to 370 nm, light having a wavelength longer than 370 nm and less than 400 nm, and light having a wavelength of 400 nm to 415 nm.
-Photopolymerization initiator F: 4,4'-bis (diethylamino) benzophenone; hydrogen abstraction type photopolymerization initiator. It has a property of absorbing light having a wavelength of 305 nm to 325 nm, light having a wavelength of 350 nm to 370 nm, light having a wavelength longer than 370 nm and less than 400 nm, and light having a wavelength of 400 nm to 415 nm.
Epoxy resin A: Biphenyl type crystalline epoxy resin (product name YX-4000 manufactured by Mitsubishi Chemical Corporation, melting point 105 ° C., epoxy equivalent 187 g / eq).
Epoxy resin B solution: A long-chain carbon chain-containing bisphenol A type epoxy resin (manufactured by DIC, product number EPICLON EXA-4816, liquid resin, epoxy equivalent 410 g / eq) is dissolved in diethylene glycol monoethyl ether acetate at a solid content of 90%. Solution (epoxy equivalent in terms of solid content 90% is 455.56 g / eq).
Epoxy resin C solution: Cresol novolac type epoxy resin (product name YDCN-704 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., softening point 87-97 ° C., epoxy equivalent 208 g / eq) at 70% solid content in diethylene glycol monoethyl ether acetate. Dissolved solution (epoxy equivalent of solid content 70% conversion is 297.14 g / eq).
-Black colorant: carbon black dispersion, average particle size 100 to 300 nm, pigment content 20%, solid content 25%, dispersion solvent: propylene glycol monomethyl ether acetate.
Blue colorant: phthalocyanine blue dispersion, average particle size 100 to 300 nm, pigment content 20%, solid content 25%, dispersion solvent: propylene glycol monomethyl ether acetate.
-Yellow colorant: nickel complex pigment dispersion liquid, average particle diameter 100 to 300 nm, pigment content 20%, solid content 25%, dispersion solvent: propylene glycol monomethyl ether acetate.
-Melamine: manufactured by Nissan Chemical Industries, Ltd., finely powdered melamine; dispersed in a photosensitive resin composition with an average particle diameter of 8 µm.
-Antioxidant: hindered phenolic antioxidant (manufactured by BASF, product number IRGANOX 1010).
-Barium sulfate: product number Variace B30 manufactured by Sakai Chemical Industry Co., Ltd.
-Bentonite: manufactured by Leox, product number Benton SD-2.
-Dispersion liquid of organic filler: crosslinked rubber (NBR) having a carboxyl group having an average primary particle diameter of 0.07 µm, manufactured by JSR Corporation, product number XER-91-MEK, methylethylketone dispersion liquid containing 15% by weight of crosslinked rubber, Acid value 10.0 mg KOH / g.
-Coupling agent: 3-glycidoxypropyltrimethoxysilane.
Defoaming agent: Shin-Etsu Chemical Co., Ltd., product number KS-66.
-Surfactant: DIC, product number Megafac F-477.
-Solvent: methyl ethyl ketone.

(3) Preparation of test sample (coating film) Using the photosensitive resin composition prepared in the above (2), a test sample (coating film) was prepared as follows.

  The photosensitive resin composition is applied onto a polyethylene terephthalate film with an applicator, and then dried by heating at 95 ° C. for 25 minutes to form a dry coating film (dry film) having a thickness of 25 μm on the film. Formed.

  A glass epoxy copper clad laminate (FR-4 type) provided with a copper foil having a thickness of 17.5 μm was prepared. A comb-shaped electrode having a line width / space width of 100 μm / 100 μm was formed as a conductor wiring on the glass epoxy copper clad laminate by a subtractive method, thereby obtaining a core material. The surface layer portion having a thickness of about 1 μm in the conductor wiring of the core material was dissolved and removed with an etching agent (organic acid-based micro etching agent manufactured by MEC Co., Ltd., product number CZ-8101) to roughen the conductor wiring. A dry film was heat-laminated with a vacuum laminator on one surface of the core material. The conditions for heat lamination are 0.5 MPa, 80 ° C., and 1 minute. In this way, a coating film having a film thickness of 25 μm made of a dry film was formed on the core material. The coating film thus obtained was evaluated as a test sample in the following (4-2) evaluation test.

(4) Evaluation test (4-1) Absorbance property By coating the photosensitive resin composition of each example on a film made of polyethylene terephthalate with an applicator, it is dried by heating at 95 ° C for 25 minutes. A dry coating film having a thickness of 10 μm was formed on the film. The dry coating film of each example formed on the polyethylene terephthalate film was set in an ultraviolet-visible near-infrared spectrophotometer (product number UV-3100PC manufactured by Shimadzu Corporation) to give a dry coating film of 300- The absorption spectrum at 800 nm was measured. As a reference, a film made of polyethylene terephthalate as a base material was used. From the obtained absorption spectrum, the value of [maximum absorbance at wavelengths 305 to 325 nm] / [maximum absorbance at wavelengths 350 to 370 nm] (that is, 305 nm with respect to the maximum absorbance of light in the wavelength range from 350 nm to 370 nm). The value of the ratio of the maximum absorbance of light in the above wavelength range of 325 nm or less was obtained and evaluated according to the following criteria.
◯: The value of [maximum absorbance at wavelengths 305 to 325 nm] / [maximum absorbance at wavelengths 350 to 370 nm] is 3 or more.
X: The value of [maximum absorbance at wavelengths 305 to 325 nm] / [maximum absorbance at wavelengths 350 to 370 nm] is less than 3.

(4-2) Shape of Hole The shape of the hole formed in the film was evaluated by exposing the test sample (coating film) of each example prepared in (3) above to development. Specifically, the test sample (coating film) of each example was subjected to an optical test by directly applying a negative mask of silica glass having a circular unexposed portion having a diameter of 60 μm onto a film made of polyethylene terephthalate. The coating film was irradiated with light through a filter and a negative mask under the condition of 400 mJ / cm ² . An ultra-high pressure mercury lamp was used as a light source for irradiating the coating film with light. As shown in FIG. 1, the emission spectrum of the light emitted by the ultra-high pressure mercury lamp is as shown in FIG. 1, where the horizontal axis represents wavelength (unit nm) and the vertical axis represents relative intensity (unit%). .. Light was irradiated under the following exposure conditions (conditions A to F). After exposure and before development, the polyethylene terephthalate film was peeled from the coating film.

  In the exposing step, an ultra-high pressure mercury lamp was used as a light source, light emitted from the ultra-high pressure mercury lamp was cut with an optical filter to a specific wavelength, and then the coating film was irradiated. Below, the wavelength of the light with which the coating film was irradiated and the optical filter used are shown. In condition C, no optical filter was used.

Condition A
The light emitted from the light source was passed through an optical filter that transmits only light in the wavelength range of 280 nm to 415 nm, and then applied to the coating film.

Condition B
The light emitted from the light source was passed through an optical filter that transmits only light in the wavelength range of 280 nm to 370 nm, and then applied to the coating film.

Condition C
The light emitted from the light source was applied to the coating film without passing through the optical filter.

Condition D
The light emitted from the light source was passed through an optical filter that transmits only light in the wavelength range of 350 nm to 370 nm, and then applied to the coating film.

Condition E
The light emitted from the light source was passed through an optical filter that transmits only light in the wavelength range of 350 nm or more and 415 nm or less, and then applied to the coating film.

Condition F
The light emitted from the light source was passed through an optical filter that transmits only light in the wavelength range of 280 nm to 325 nm, and then applied to the coating film.

The coating film (film) after exposure was subjected to development processing. In the development processing, a 1% Na ₂ CO ₃ aqueous solution at 30 ° C. was sprayed onto the film at a spray pressure of 0.2 MPa for 90 seconds. Subsequently, the coating was cleaned by spraying pure water at a spray pressure of 0.2 MPa for 90 seconds. This removed the unexposed portions of the coating to form holes. The coating was subsequently heated at 160 ° C. for 60 minutes. Thus, a layer made of a cured product of the photosensitive resin composition (also called a cured product of a dry film) was formed on the core material. This obtained the test piece.

The inner diameter of one end and the inner diameter of the other end of the hole in the test piece were measured, and the shape of the hole was evaluated based on the difference between the two inner diameters according to the following criteria.
A: The difference in inner diameter is less than 4 μm.
B: The difference in inner diameter is 4 μm or more and less than 6 μm.
C: The difference in inner diameter is 6 μm or more and less than 8 μm.
D: The difference in inner diameter is 8 μm or more and less than 10 μm.
E: The difference in inner diameter is 10 μm or more.
F: Porosity could not be formed because the coating film could not be sufficiently photocured.

  In Example 2, when the coating film of the photosensitive resin composition was exposed under the condition A and then developed, the difference in the inner diameters of the holes was small as shown in FIG. 2A. That is, the shape of the film formed from the photosensitive resin composition had high resolution, and the shape of the pores formed in the film was sharp. In Examples other than Example 2, the same result was obtained when the exposure and development were performed under the condition A.

  On the other hand, in Example 2, when the coating film of the photosensitive resin composition was similarly exposed and developed under the condition C and the condition D, as shown in FIG. 2B and FIG. Has grown. That is, the resolution of the shape of the film formed from the photosensitive resin composition was lowered, and the shape of the holes formed in the film was disturbed. In Examples other than Example 2, the same results were obtained when exposure and development were performed under the conditions C and D.

  In the examples, the test pieces obtained under the conditions A and B were evaluated in the following (4-3) to (4-7).

(4-3) Insulation While applying a bias voltage of DC 12 V to the conductor wiring (comb-shaped electrode) in the test piece, the test piece was heated at 130 ° C. and 85% R. H. Exposure for 100 hours under the test environment. The electrical resistance value between the comb-shaped electrodes of the layer made of the cured product under this test environment was constantly measured, and the result was evaluated as follows.
A: The electric resistance value was constantly maintained at 10 ⁶ Ω or more from the start of the test until 100 hours passed.
B: The electric resistance value was constantly maintained at 10 ⁶ Ω or more until 70 hours passed from the start of the test, but the electric resistance value became less than 10 ⁶ Ω before 100 hours passed from the start of the test.
C: The electric resistance value was less than 10 ⁶ Ω before 70 hours had elapsed from the start of the test.

(4-4) Acid resistance After immersing the test piece in a 10% sulfuric acid aqueous solution for 30 minutes at room temperature, the appearance of the layer formed of the cured product was observed. The results were evaluated as shown below.
A: No abnormalities such as swelling, peeling and discoloration are observed in the layer formed of the cured product.
B: Abnormalities such as swelling, peeling and discoloration are slightly observed in the layer formed of the cured product.
C: Abnormalities such as swelling, peeling and discoloration are remarkably observed in the layer made of the cured product.

(4-5) Alkali resistance After immersing the test piece in a sodium hydroxide aqueous solution having a concentration of 10% by mass for 1 hour at room temperature, the appearance of the layer formed of the cured product was observed. The results were evaluated as shown below.
A: No abnormalities such as swelling, peeling and discoloration are observed in the layer formed of the cured product.
B: Abnormalities such as swelling, peeling and discoloration are slightly observed in the layer formed of the cured product.
C: Abnormalities such as swelling, peeling and discoloration are remarkably observed in the layer made of the cured product.

(4-6) Solder heat resistance A water-soluble flux (Lonco 3355-11, manufactured by London Chemical Co., Ltd.) is applied to a layer made of a cured product of a test piece, and subsequently a layer made of the cured product is melted at 260 ° C. It was immersed in the bath for 10 seconds and then washed with water. After repeating this treatment three times, the appearance of the layer made of the cured product was observed, and the results were evaluated as shown below.
A: No abnormalities such as swelling, peeling and discoloration are observed in the layer formed of the cured product.
B: Abnormalities such as swelling, peeling and discoloration are slightly observed in the layer formed of the cured product.
C: Abnormalities such as swelling, peeling and discoloration are remarkably observed in the layer made of the cured product.

(4-7) Plating Resistance A test piece was sequentially subjected to electroless nickel plating and electroless gold plating using a commercially available plating solution, and then the state of the plated layer and the layer made of a cured product was confirmed.

  Then, the cellophane adhesive tape peeling test of the layer made of the cured product was performed to confirm the adhesion state of the layer made of the cured product after plating.

The result was evaluated as follows.
A: No change in appearance was observed in the layer made of the cured product before and after the formation of the plated layer, no penetration of plating was observed, and no peeling of the layer made of the cured product was observed in the cellophane adhesive tape peeling test.
B: No change in appearance was observed in the layer made of the cured product before and after the formation of the plated layer, but partial peeling of the layer made of the cured product was observed in the cellophane adhesive tape peeling test.
C: Lifting of the cured product layer was observed after the formation of the plated layer, and peeling of the cured product layer was observed in the cellophane adhesive tape peel test.

1 Core Material 2 Insulating Layer 3 Conductive Layer 31 First Conductor Wiring 4 Coating 5 Unexposed Area 6 Hole 7 Interlayer Insulating Layer 8 Second Conductor Wiring 9 Hole Plating 10 Through Hole 11 Printed Wiring Board 40 Coating

Claims (12)

By disposing the photosensitive resin composition on the substrate, a step of forming a coating film on the substrate,
Exposing the coating film to light emitted from a light source,
A step of developing the coating film after the exposure with an alkaline solution,
A method of manufacturing a film,
The photosensitive resin composition includes a carboxyl group-containing resin (A), an unsaturated compound (B) having at least one ethylenically unsaturated bond in one molecule, a photopolymerization initiator (C), and an epoxy resin. (D) and,
The light absorption spectrum of the photopolymerization initiator (C) is
A first absorption in the wavelength range of 350 nm to 370 nm, and
A second absorption in the wavelength range longer than 370 nm and less than or equal to 415 nm,
The spectrum of light applied to the coating film in the exposing step is
A first intensity distribution having a wavelength overlapping the wavelength of the first absorption within a wavelength range of 350 nm or more and 370 nm or less;
A second intensity distribution in a wavelength range longer than 370 nm and equal to or shorter than 415 nm and overlapping the wavelength of the second absorption;
And a third intensity distribution within a wavelength range of 305 nm to 325 nm,
And the total percentage of the area under the curve in the wavelength range shorter than 280 nm and up to 200 nm and the area under the curve in the wavelength range longer than 415 nm and up to 500 nm is 5% or less with respect to the area under the curve in the wavelength range from 200 nm to 500 nm. Is
Method of manufacturing film. The second absorption includes at least absorption in a wavelength range longer than 400 nm and not longer than 415 nm,
The second intensity distribution includes at least an intensity distribution having a wavelength overlapping with the wavelength of the second absorption in a wavelength range longer than 400 nm and not more than 415 nm.
The method for producing a film according to claim 1. The light absorption spectrum of the photopolymerization initiator (C) further has a third absorption within a wavelength range of 305 nm to 325 nm,
The third intensity distribution includes at least an intensity distribution having a wavelength overlapping the wavelength of the third absorption within a wavelength range of 305 nm or more and 325 nm or less,
The method for producing a film according to claim 1 or 2. In the absorption spectrum of light of the coating film, the maximum absorbance in the wavelength range of 305 nm to 325 nm is 3 times or more the maximum absorbance in the wavelength range of 350 nm to 370 nm.
The manufacturing method of the film as described in any one of Claim 1 to 3. The light source is at least one selected from the group consisting of a metal halide lamp, a high-pressure mercury lamp, and an ultra-high-pressure mercury lamp,
The method for producing the coating film according to claim 1. In the exposing step, the light emitted from the light source is passed through an optical filter, and then the coating film is irradiated.
The optical filter cuts light in a wavelength range shorter than 280 nm and 200 nm or more and light in a wavelength range longer than 415 nm and 500 nm or less,
The method for producing the coating film according to claim 1. The photopolymerization initiator (C) is composed of an acylphosphine oxide photopolymerization initiator (C1), an α-aminoalkylphenone photopolymerization initiator (C2), and an oxime ester photopolymerization initiator (C3). Contains at least one selected from the group,
A method for producing the coating film according to claim 1. The photopolymerization initiator (C) contains a hydrogen abstraction type photopolymerization initiator (C4),
A method for producing the coating film according to claim 1. The carboxyl group-containing resin (A) includes a carboxyl group-containing resin having an ethylenically unsaturated group,
A method for producing the coating film according to claim 1. The photosensitive resin composition includes a component having a bisphenolfluorene skeleton,
The method for producing a film according to claim 1. The photosensitive resin composition further has a color pigment (E),
A method for producing the coating film according to claim 1. A conductive layer and an insulating layer overlapping the conductive layer,
The insulating layer includes a film produced by the method for producing a film according to any one of claims 1 to 11.
Printed wiring board.