JP2017197663A - Carboxyl group-containing resin, photosensitive resin composition, dry film, printed wiring board, and method for producing carboxyl group-containing resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a carboxyl group-containing resin that can impart high electric insulation and plating resistance to a cured product of a photosensitive resin composition.SOLUTION: A carboxyl group-containing resin (A1) is a reactant between: an intermediate, which is a reactant of an epoxy compound (a1) with an unsaturated group-containing monocarboxylic acid (a2) and a polycarboxylic acid (a6); and acid anhydride. The epoxy compound (a1) has a bisphenol fluorene skeleton represented by formula (1) (Rindependently represent H, alkyl or halogen).SELECTED DRAWING: Figure 1

Description

  The present invention relates to a carboxyl group-containing resin, a photosensitive resin composition containing the carboxyl group-containing resin, a dry film containing a dried product of the photosensitive resin composition, and an interlayer insulation containing a cured product of the photosensitive resin composition. It is related with the manufacturing method of the printed wiring board provided with a layer, the printed wiring board provided with the soldering resist layer containing the hardened | cured material of the said photosensitive resin composition, and the said carboxyl group containing resin.

  Conventionally, an electrically insulating resin composition has been used to form electrically insulating layers such as a solder resist layer, a plating resist layer, an etching resist layer, and an interlayer insulating layer of a printed wiring board. Such a resin composition is, for example, a photosensitive resin composition.

  In order to give high heat resistance to the layer formed from the photosensitive resin composition, it has been proposed to add a carboxyl group-containing resin having a bisphenolfluorene skeleton to the photosensitive resin composition. For example, Patent Document 1 discloses that a carboxyl group-containing resin having a fluorene skeleton obtained by reacting fluorene epoxy (meth) acrylate with a polyvalent carboxylic acid or an anhydride thereof is used.

  However, the developability of the photosensitive resin composition containing a carboxyl group-containing resin having a fluorene skeleton is low. For this reason, it has been difficult to produce an electrically insulating layer having a sufficient thickness for a solder resist layer, an interlayer insulating layer and the like from this photosensitive resin composition by a photolithography method. In particular, in recent years, it has been required to use an alkaline aqueous solution containing at least one of an alkali metal salt and an alkali metal hydroxide as a developing solution in order to improve the working environment and reduce the burden of waste disposal. It has been difficult to develop a photosensitive resin composition containing a carboxyl group-containing resin having a fluorene skeleton with an alkaline aqueous solution. Further, in order to improve developability, it is necessary to lower the molecular weight of the carboxyl group-containing resin having a fluorene skeleton. In that case, the tackiness of the film formed from the photosensitive resin composition increases, or the solder resist layer There arises a problem that the electrical insulation property and plating resistance of the material deteriorate.

Japanese Patent No. 4508929

  An object of the present invention is suitable as a component of a photosensitive resin composition, and can impart developability with an alkaline aqueous solution excellent in the photosensitive resin composition while having a fluorene skeleton, and also cures the photosensitive resin composition. Carboxy group-containing resin capable of imparting high electrical insulation and plating resistance to a product, photosensitive resin composition containing the carboxyl group-containing resin, dry film containing a dried product of the photosensitive resin composition, and the photosensitive resin It is to provide a printed wiring board provided with an interlayer insulating layer containing a cured product of the composition, a printed wiring board provided with a solder resist layer containing a cured product of the photosensitive resin composition, and a method for producing a carboxyl group-containing resin. .

The carboxyl group-containing resin (A1) according to one embodiment of the present invention includes an intermediate that is a reaction product of the epoxy compound (a1), the unsaturated group-containing monocarboxylic acid (a2), and the polyvalent carboxylic acid (a6). , And a reaction product of an acid anhydride. The epoxy compound (a1) has a bisphenol fluorene skeleton, and the bisphenol fluorene skeleton is represented by the following formula (1). In the following formula (1), R _{1 to} R ₈ are each independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or halogen.

  A photosensitive resin composition according to one embodiment of the present invention 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 compound (D), and the carboxyl group-containing resin (A) contains the carboxyl group-containing resin (A1).

  The dry film which concerns on 1 aspect of this invention contains the dried material of the said photosensitive resin composition.

  The printed wiring board which concerns on 1 aspect of this invention is equipped with the interlayer insulation layer containing the hardened | cured material of the said photosensitive resin composition.

  The printed wiring board which concerns on 1 aspect of this invention is equipped with the soldering resist layer containing the hardened | cured material of the said photosensitive resin composition.

In the method for producing a carboxyl group-containing resin (A1) according to one embodiment of the present invention, an epoxy compound (a1), an unsaturated group-containing monocarboxylic acid (a2), and a polyvalent carboxylic acid (a6) are reacted. And synthesizing the carboxyl group-containing resin (A1) by reacting the intermediate with an acid anhydride. The epoxy compound (a1) has a bisphenolfluorene skeleton. The bisphenolfluorene skeleton is represented by the above formula (1), and in the formula (1), R _{1 to} R ₈ are each independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or halogen.

  According to one embodiment of the present invention, it is suitable as a component of a photosensitive resin composition, and can impart developability with an alkaline aqueous solution excellent in the photosensitive resin composition while having a fluorene skeleton. A carboxyl group-containing resin capable of imparting high electrical insulation and plating resistance to a film formed from the product, a photosensitive resin composition containing the carboxyl group-containing resin, a dry film containing the photosensitive resin composition, A printed wiring board provided with an interlayer insulating layer containing a cured product of a photosensitive resin composition, a printed wiring board provided with a solder resist layer containing a cured product of the photosensitive resin composition, and a method for producing the carboxyl group-containing resin are obtained. It is done.

1A to 1E are cross-sectional views showing a process for manufacturing a multilayer printed wiring board.

  Hereinafter, an embodiment of the present invention will be described. In the following description, “(meth) acryl” means at least one of “acryl” and “methacryl”. For example, (meth) acrylate means at least one of acrylate and methacrylate.

  The carboxyl group-containing resin (A1) according to this embodiment is suitable as a component of the photosensitive resin composition. The photosensitive resin composition includes, for example, 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. Compound (D), and carboxyl group-containing resin (A) contains carboxyl group-containing resin (A1).

The carboxyl group-containing resin (A1) includes an epoxy compound (a1), an intermediate that is a reaction product of the unsaturated group-containing monocarboxylic acid (a2) and the polyvalent carboxylic acid (a6), and an acid anhydride. It is a reactant. The epoxy compound (a1) is represented by the following formula (1). In the formula (1), R _{1 to} R ₈ are each independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or a halogen, and a bisphenolfluorene skeleton. Have.

  The carboxyl group-containing resin (A1) is obtained by reacting an epoxy compound (a1) with an unsaturated group-containing monocarboxylic acid (a2) and a polyvalent carboxylic acid (a6), and an intermediate obtained thereby. It is synthesized by reacting things.

Each of R _{1 to} R ₈ in Formula (1) may be hydrogen, but may be an alkyl group having 1 to 5 carbon atoms or a halogen. This is because even if hydrogen in the aromatic ring is substituted with a low molecular weight alkyl group or halogen, the physical properties of the carboxyl group-containing resin (A1) are not adversely affected, but 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 this embodiment, since 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) is used. High heat resistance and insulation reliability can be imparted.

  Further, the carboxyl group-containing resin (A1) is an intermediate that is a reaction product of the epoxy compound (a1), the unsaturated group-containing monocarboxylic acid (a2), and the polyvalent carboxylic acid (a6), an acid anhydride, The carboxyl group-containing resin (A1) can have an appropriate molecular weight and an appropriate acid value. For this reason, the developability of the photosensitive resin composition containing the carboxyl group-containing resin (A1) can be improved, and the photosensitive resin composition contains an alkaline aqueous solution containing at least one of an alkali metal salt and an alkali metal hydroxide. It is also possible to impart developability. Further, the insulation reliability and plating resistance of the cured product of the photosensitive resin composition are improved.

  The carboxyl group-containing resin (A1) will be described more specifically. In order to synthesize the carboxyl group-containing resin (A1), first, a part of the epoxy group (see formula (2)) in the epoxy compound (a1) is reacted with the unsaturated group-containing monocarboxylic acid (a2). The intermediate is synthesized by reacting another part of the epoxy group with the polyvalent carboxylic acid (a6).

  The intermediate includes a structure (S3) represented by the following formula (3) generated by a ring-opening addition reaction between an epoxy group and an unsaturated group-containing monocarboxylic acid (a2), an epoxy group, a polyvalent carboxylic acid (a6), and And a structure (S4) represented by the following formula (4) produced by the ring-opening addition reaction. That is, the intermediate has a secondary hydroxyl group generated by the ring-opening addition reaction between the epoxy group and the unsaturated group-containing monocarboxylic acid (a2) in the structure (S3), and in the structure (S4), It has a secondary hydroxyl group and a carboxyl group produced by a ring-opening addition reaction between an epoxy group and a polyvalent carboxylic acid (a6). In the formula (3), A is an unsaturated group-containing carboxylic acid residue, and in the formula (4), Y is a polyvalent carboxylic acid residue. In addition, when the structure (S4) shown by Formula (4) arises by the reaction of the epoxy group of two molecules of the epoxy compound (a1) and one molecule of the polyvalent carboxylic acid (a6), this structure (S4) bridges the molecules of the two epoxy compounds (a1). In this case, the molecular weight of the intermediate can be increased.

  In addition, some carboxyl groups in the polyvalent carboxylic acid (a6) may remain in the intermediate without reacting with the epoxy group. That is, the intermediate may have a carboxyl group derived from the polyvalent carboxylic acid (a6).

  Next, at least a part of the secondary hydroxyl group in the intermediate is reacted with the acid anhydride. The acid anhydride contains, for example, at least one of acid dianhydride (a3) and acid monoanhydride (a4). Thereby, carboxyl group-containing resin (A1) can be synthesized. Therefore, the carboxyl group-containing resin (A1) has a bisphenolfluorene skeleton represented by the formula (1).

  When the acid anhydride contains acid monoanhydride (a4), the carboxyl group-containing resin (A1) includes a structure (S5) shown in the following formula (5) and a structure (S6) shown in the following formula (6). Have. The structure (S5) is generated by adding an acid monoanhydride (a4) to the secondary hydroxyl group in the structure (S3). The structure (S6) is generated by adding an acid monoanhydride (a4) to the secondary hydroxyl group in the structure (S4). In Formula (5) and Formula (6), B is an acid monoanhydride residue. In this case, the carboxyl group-containing resin (A1) has a carboxyl group derived from the acid monoanhydride (a4).

  When the acid anhydride contains acid dianhydride (a3), the carboxyl group-containing resin (A1) includes a structure (S7) represented by the following formula (7) and a structure (S8) represented by the following formula (8): And a structure (S9) represented by the following formula (9). Structures (S7) to (S9) are generated by the reaction between two acid anhydride groups in the acid dianhydride (a3) and two secondary hydroxyl groups in the intermediate. That is, the structures (S7) to (S9) are generated by crosslinking the two secondary hydroxyl groups with the acid dianhydride (a3). Of these, the structure (S7) is generated by the acid dianhydride (a3) cross-linking two secondary hydroxyl groups in the two structures (S3). The structure (S8) is generated by the acid dianhydride (a3) cross-linking two secondary hydroxyl groups in the two structures (S4). The structure (S9) is generated by the acid dianhydride (a3) cross-linking two secondary hydroxyl groups in the structure (S3) and the structure (S4), respectively. In Formula (7) and Formula (8), D is an acid dianhydride residue. When the carboxyl group-containing resin (A) has the structures (S7) to (S9) as described above, the carboxyl group-containing resin (A) has a carboxyl group derived from the acid dianhydride (a3). In order to particularly improve the developability of the photosensitive resin composition with an alkaline aqueous solution, the amount of carboxyl groups in the structure (S8) with respect to the total amount of carboxyl groups in the carboxyl group-containing resin (A1) is 50 mol% or less. It is preferable that it is 30 mol% or less.

  In addition, the case where two secondary hydroxyl groups present in one molecule of the intermediate are crosslinked and the case where two secondary hydroxyl groups present in each of the two molecules of the intermediate are crosslinked It is possible. When two secondary hydroxyl groups respectively present in the two molecules of the intermediate are cross-linked, the molecular weight of the carboxyl group-containing resin (A) increases.

  When some of the epoxy groups in the epoxy compound (a1) remain unreacted during the synthesis of the intermediate, the carboxyl group-containing resin (A1) may have a structure (S2), that is, an epoxy group. Further, when a part of the structure (S3) and the structure (S4) in the intermediate remains unreacted, the carboxyl group-containing resin (A1) may have the structure (S3) and the structure (S4). . In addition, one of the two secondary hydroxyl groups in the structure (S4) may remain unreacted.

  However, in this embodiment, the epoxy group derived from the structure (S2) in the carboxyl group-containing resin (A1) and the structure (S3) are optimized by optimizing the reaction conditions during the synthesis of the carboxyl group-containing resin (A1). ) And the structure (S4), or the number of these epoxy groups and hydroxyl groups can be almost eliminated.

  When the epoxy compound (a1) itself has a secondary hydroxyl group, that is, for example, when n = 1 or more in the formula (10) described later, the carboxyl group-containing resin (A1) is an epoxy compound (a1). The secondary secondary hydroxyl group may have a structure produced by a reaction with at least one of acid dianhydride (a3) and acid dianhydride (a4).

  In addition, the structure of the above-mentioned carboxyl group-containing resin (A1) is reasonably inferred based on technical common sense, and the structure of the carboxyl group-containing resin (A1) cannot be specified by analysis. The reason is as follows. When the epoxy compound (a1) itself has a secondary hydroxyl group (for example, when n is 1 or more in the formula (10)), the carboxyl group-containing resin depends on the number of secondary hydroxyl groups in the epoxy compound (a1). The structure of (A1) changes greatly. When the intermediate and the acid dianhydride (a3) react, as described above, two secondary hydroxyl groups present in one molecule of the intermediate are acid dianhydrides (a3). There may be a case where two secondary hydroxyl groups respectively present in two molecules of the intermediate are crosslinked with an acid dianhydride (a3). Further, at the time of synthesizing the intermediate, a part of the carboxyl group of the polyvalent carboxylic acid (a6) does not react with the epoxy compound (a1) and remains in the intermediate, which may remain in the carboxyl group-containing resin (A1). It is possible. In addition, a part of the secondary hydroxyl group in the intermediate may remain without reacting with the acid dianhydride (a3) and the acid monoanhydride (a4). In addition, a part of the acid anhydride group in the acid dianhydride (a3) may remain without reacting. In these cases, the carboxyl group-containing resin (A1) can further have various structures. For this reason, the carboxyl group-containing resin (A1) finally obtained contains a plurality of molecules having different structures, and even when the carboxyl group-containing resin (A1) is analyzed, the structure cannot be specified.

  Since the carboxyl group-containing resin (A1) has an ethylenically unsaturated group derived from the unsaturated group-containing monocarboxylic acid (a2), it has photoreactivity. For this reason, carboxyl group-containing resin (A1) can impart photosensitivity (specifically, ultraviolet curable) to the photosensitive resin composition. Moreover, since the carboxyl group-containing resin (A1) has a carboxyl group derived from an acid anhydride, the photosensitive resin composition contains at least one of an alkali metal salt and an alkali metal hydroxide. It is possible to impart developability with an aqueous solution. Furthermore, the molecular weight of the carboxyl group-containing resin (A1) depends on the number of crosslinks by the polyvalent carboxylic acid (a6). For this reason, the carboxyl group-containing resin (A1) in which the acid value and the molecular weight are appropriately adjusted is obtained. That is, by controlling the amount of acid anhydride and the amount of unsaturated group-containing monocarboxylic acid (a2) relative to polyvalent carboxylic acid (a6), a carboxyl group-containing resin (A1) having a desired molecular weight and acid value Is easily obtained.

  The weight average molecular weight of the carboxyl group-containing resin (A1) is preferably in the range of 1000 to 5000. When the weight average molecular weight is 1000 or more, tackiness of a film formed from the photosensitive resin composition is further suppressed, and insulation reliability and plating resistance of the cured product are further improved. Moreover, the developability by the alkaline aqueous solution of the photosensitive resin composition improves especially that a weight average molecular weight is 5000 or less. The weight average molecular weight of the carboxyl group-containing resin (A1) is calculated from the measurement result of the molecular weight under the following conditions by gel permeation chromatography.

GPC device: SHODEX 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 ° C
Detector: RI,
Conversion: Polystyrene.

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

  The raw material of the carboxyl group-containing resin (A1) and the reaction conditions during the synthesis of the carboxyl group-containing resin (A1) will be described in detail.

  The epoxy compound (a1) has a structure (S10) represented by the following formula (10), for example. N in Formula (10) is a number within the range of 0-20, for example. In order to adjust the molecular weight of the carboxyl group-containing resin (A1) to an appropriate value, the average of n is particularly preferably in the range of 0-1. If the average of n is in the range of 0 to 1, particularly when the acid anhydride contains acid dianhydride (a3), an excessive increase in molecular weight due to addition of acid dianhydride (a3) is suppressed. Cheap.

  The unsaturated group-containing monocarboxylic acid (a2) can contain, for example, a compound having only one ethylenically unsaturated group in one molecule. More specifically, the unsaturated group-containing monocarboxylic acid (a2) is, for example, acrylic acid, methacrylic acid, ω-carboxy-polycaprolactone (n≈2) monoacrylate, crotonic acid, cinnamic acid, 2-acryloyloxyethyl. 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 2-methacryloyloxyethyl maleic acid, β-carboxyethyl acrylate, 2-acryloyloxyethyl tetrahydrophthalic acid, 2-methacryloyloxyethyl tetrahydrophthalic acid, 2-acryloyloxyethyl hexahydrophthalate It can contain at least one compound selected from the group consisting of phosphoric acid and 2-methacryloyloxyethyl hexahydrophthalic acid. Preferably, the unsaturated group-containing monocarboxylic acid (a2) contains acrylic acid.

  The polyvalent carboxylic acid (a6) is a compound having two or more carboxyl groups in one molecule. The polyvalent carboxylic acid (a6) preferably contains a dicarboxylic acid that is a compound having two carboxyl groups in one molecule. In this case, an excessive increase in molecular weight can be prevented. The polyvalent carboxylic acid (a6) may contain only a dicarboxylic acid. The polyvalent carboxylic acid (a6) may or may not have an ethylenically unsaturated group. More specifically, the polyvalent carboxylic acid (a6) is, for example, oxalic acid, malonic acid, succinic acid, methyl succinic acid, itaconic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, maleic acid. Acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, methanetricarboxylic acid, tricarballylic acid, benzenetricarboxylic acid, benzenetetracarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid, trimellitic acid, cyclohexane-1, It contains at least one compound selected from the group consisting of 2,4-tricarboxylic acid, pyromellitic acid, benzophenone tetracarboxylic acid, and biphenyl tetracarboxylic acid.

  In reacting the epoxy compound (a1) with the unsaturated group-containing monocarboxylic acid (a2) and the polyvalent carboxylic acid (a6), a known method may be employed. For example, an unsaturated group-containing monocarboxylic acid (a2) and a polyvalent carboxylic acid (a6) are added to a solvent solution of the epoxy compound (a1), and if necessary, a thermal polymerization inhibitor and a catalyst are added and mixed with stirring. To obtain a reactive solution. An intermediate can be obtained by reacting this reactive solution at a temperature of preferably 60 to 150 ° C., particularly preferably 80 to 120 ° C., by a conventional method. Solvents include, for example, 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, propylene glycol monomethyl ether It can contain at least one component selected from the group consisting of acetates such as acetate and dialkyl glycol ethers. 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. A kind of component can be contained.

  It is particularly preferred that the catalyst contains triphenylphosphine. That is, it is preferable to react the epoxy compound (a1) with the unsaturated group-containing monocarboxylic acid (a2) and the polyvalent carboxylic acid (a6) in the presence of triphenylphosphine. In this case, the ring-opening addition reaction of the epoxy group in the epoxy compound (a1) with the unsaturated group-containing monocarboxylic acid (a2) and the polyvalent carboxylic acid (a6) is particularly promoted, 95% or more, or 97% or more, Alternatively, a reaction rate (conversion rate) of almost 100% can be achieved. For this reason, the intermediate body which has a structure (S3) is obtained with a high yield. Moreover, generation | occurrence | production of the ion migration in the layer containing the hardened | cured material of the photosensitive resin composition is suppressed, and the insulation reliability of the same layer improves further.

  When reacting the epoxy compound (a1) with the unsaturated group-containing monocarboxylic acid (a2) and the polyvalent carboxylic acid (a6), the unsaturated group-containing monocarboxylic acid with respect to 1 mol of the epoxy group of the epoxy compound (a1) The total of carboxyl groups in (a2) is preferably in the range of 0.5 to 0.95 mol. Moreover, the unsaturated group containing monocarboxylic acid with respect to 1 mol of epoxy groups of the epoxy compound (a1) at the time of making an epoxy compound (a1) react with unsaturated group containing monocarboxylic acid (a2) and polyhydric carboxylic acid (a6) The total of carboxyl groups in (a2) and polyvalent carboxylic acid (a6) is preferably in the range of 0.8 to 1.2 mol. In this case, a photosensitive resin composition having excellent storage stability can be obtained. Moreover, it is preferable that the quantity of the carboxyl group in polyhydric carboxylic acid (a6) with respect to 1 mol of carboxyl groups in unsaturated group containing monocarboxylic acid (a2) exists in the range of 0.05-2 mol. In this case, the photosensitive resin composition can have particularly good photosensitivity, and the film formed from the photosensitive resin composition can have particularly good photosensitivity and particularly low tackiness. The cured product of the photosensitive resin composition can have particularly good insulation reliability and plating resistance.

  It is also preferable to react the epoxy compound (a1) with the unsaturated group-containing monocarboxylic acid (a2) and the polyvalent carboxylic acid (a6) under air bubbling. In this case, since the addition polymerization reaction of the unsaturated group is suppressed, the increase in the molecular weight of the intermediate and the gelation of the intermediate solution can be suppressed. Moreover, the excessive coloring of carboxyl group-containing resin (A1) which is a final product can be suppressed.

  The intermediate obtained in this way is a hydroxyl group produced by the reaction of the epoxy group of the epoxy compound (a1) and the carboxyl group of the unsaturated group-containing monocarboxylic acid (a2), and the epoxy group of the epoxy compound (a1). And a hydroxyl group produced by a reaction of the carboxyl group of the polyvalent carboxylic acid (a6).

  As described above, the acid anhydride can contain at least one of acid dianhydride (a3) and acid monoanhydride (a4).

  The acid dianhydride (a3) is a compound having two acid anhydride groups. The acid dianhydride (a3) can contain an anhydride of tetracarboxylic acid. Acid dianhydride (a3) is, for example, 1,2,4,5-benzenetetracarboxylic dianhydride, benzophenone tetracarboxylic dianhydride, methylcyclohexene tetracarboxylic dianhydride, tetracarboxylic dianhydride, Naphthalene-1,4,5,8-tetracarboxylic dianhydride, ethylenetetracarboxylic dianhydride, 9,9'-bis (3,4-dicarboxyphenyl) fluorene dianhydride, glycerin bisanhydrotri Melitate monoacetate, ethylene glycol bisanhydro trimellitate, 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-buta Tetracarboxylic dianhydride, and 3,3 ', may contain at least one compound selected from the group consisting of 4,4'-biphenyl tetracarboxylic acid dianhydride. In particular, the acid dianhydride (a3) preferably contains 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride. That is, it is preferable that D in Formula (5) and Formula (6) includes a 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride residue. In this case, while ensuring good developability of the photosensitive resin composition, it is possible to further suppress the tackiness of a film formed from the photosensitive resin composition and further improve the insulation reliability and plating resistance of the cured product. . The amount of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride relative to the total amount of acid dianhydride (a3) is preferably in the range of 20 to 100 mol%, and in the range of 40 to 100 mol%. Although it is more preferable to be within, it is not restricted to these ranges.

  The acid monoanhydride (a4) is a compound having one acid anhydride group. The acid monoanhydride (a4) can contain an anhydride of a dicarboxylic acid. Examples of the acid monoanhydride (a4) include phthalic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic acid anhydride, hexahydrophthalic anhydride, methylhexa Hydrophthalic anhydride, succinic anhydride, methyl succinic anhydride, maleic anhydride, citraconic anhydride, glutaric anhydride, cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride, and It can contain at least one compound selected from the group consisting of itaconic anhydride. In particular, it is preferable that the acid monoanhydride (a4) contains 1,2,3,6-tetrahydrophthalic anhydride. That is, it is preferable that B in Formula (4) contains a 1,2,3,6-tetrahydrophthalic anhydride residue. In this case, while ensuring good developability of the photosensitive resin composition, it is possible to further suppress the tackiness of a film formed from the photosensitive resin composition and further improve the insulation reliability and plating resistance of the cured product. . The amount of 1,2,3,6-tetrahydrophthalic anhydride relative to the total amount of acid monoanhydride (a4) is preferably in the range of 20 to 100 mol%, and preferably in the range of 40 to 100 mol%. Although more preferable, it is not limited to these ranges.

  At least one of the acid dianhydride (a3) and the acid monoanhydride (a4) may include an acid anhydride (a5) having a carboxyl group and having an alicyclic skeleton. In this case, the amount of carboxyl groups contained in the carboxyl group-containing resin (A1) can be increased. Thereby, the developability by the alkaline aqueous solution of the photosensitive resin composition further improves. Further, since the carboxyl group-containing resin (A1) has an alicyclic skeleton derived from the acid anhydride (a5), the tackiness of the film formed from the photosensitive resin composition is further suppressed and the resistance to resistance is increased. Plating property and solder heat resistance are further improved.

  The acid anhydride (a5) is preferably contained in the acid monoanhydride (a4). That is, it is preferable that B in Formula (5) and Formula (6) includes a residue of acid anhydride (a5). The acid anhydride (a5) contains at least one alicyclic compound such as cycloalkane, cycloalkene, bicyclic compound, polycyclic compound, and spiro compound. In particular, the acid anhydride (a5) is preferably a compound containing a cycloalkane. Examples of cycloalkane include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, and cyclooctane. More preferably, the acid anhydride (a5) is a compound containing cyclohexane. The acid anhydride (a5) preferably has a carboxyl group directly bonded to the alicyclic skeleton. Furthermore, the acid anhydride group in the acid anhydride (a5) is preferably directly bonded to the alicyclic skeleton. The acid anhydride (a5) may not contain an aromatic ring. The acid anhydride (a5) may be a tricarboxylic acid anhydride.

  More preferably, the acid anhydride (a5) contains cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride. That is, it is preferable that B in Formula (5) and Formula (6) includes a cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride residue. In this case, the structure (S4) has two carboxyl groups and an alicyclic skeleton, the tackiness of the film formed from the photosensitive resin composition is reduced, and the insulation reliability and resistance of the cured product are reduced. Plating properties are improved and good developability is ensured. Further, since cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride has high water solubility and good reactivity, the production of the carboxyl group-containing resin (A1) is facilitated.

  In reacting the intermediate with the acid anhydride, a known method can be employed. For example, an acid anhydride is added to the solvent solution of the intermediate, and a thermal polymerization inhibitor and a catalyst are further added as necessary, followed by stirring and mixing to obtain a reactive solution. A carboxyl group-containing resin (A1) is obtained by reacting this reactive solution at a temperature of preferably 60 to 150 ° C., particularly preferably 80 to 120 ° C., by a conventional method. As the solvent, catalyst and thermal polymerization inhibitor, appropriate ones can be used, and the solvent, catalyst and thermal polymerization inhibitor used in 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 an intermediate with an acid anhydride in the presence of triphenylphosphine. In this case, the reaction between the secondary hydroxyl group and the acid anhydride in the intermediate is particularly accelerated, and a reaction rate (conversion rate) of 90%, 95%, 97%, or almost 100% can be achieved. For this reason, the carboxyl group-containing resin (A1) having the structure (S4) and the structure (S5) is obtained in a high yield. Moreover, generation | occurrence | production of the ion migration in the layer containing the hardened | cured material of the photosensitive resin composition is suppressed, and the insulation reliability of the same layer improves further.

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

  When the acid anhydride contains acid monoanhydride (a4) and acid dianhydride (a3), the amount of acid dianhydride (a3) is 0 with respect to 1 mol of the epoxy group of the epoxy compound (a1). It is preferably within the range of 0.05 to 0.24 mol. Moreover, it is preferable that the quantity of acid monoanhydride (a4) exists in the range of 0.3-0.7 mol with respect to 1 mol of epoxy groups of an epoxy compound (a1). In this case, the carboxyl group-containing resin (A1) in which the acid value and the molecular weight are appropriately adjusted can be easily obtained. Moreover, the excessive increase in molecular weight of the produced carboxyl group-containing resin (A1) is suppressed.

  When the acid anhydride contains acid monoanhydride (a4) and acid dianhydride (a3), the intermediate is reacted with acid monoanhydride (a4) and acid dianhydride (a3) at a time. Also good.

  When the acid anhydride contains acid monoanhydride (a4) and acid dianhydride (a3), the product is first synthesized by reacting the intermediate with acid dianhydride (a3). The product and acid monoanhydride (a4) may be reacted. That is, the carboxyl group-containing resin (A1) may be a reaction product of a product that is a reaction product of an intermediate and an acid dianhydride (a3) and an acid monoanhydride (a4). In this case, since the reaction between the intermediate and the acid dianhydride (a3) proceeds stably without competing with the reaction with the acid monoanhydride (a4), the structure (S7) is stably generated. Cheap. Furthermore, the structure of the molecules in the product is less likely to vary. For this reason, also in the carboxyl group-containing resin (A1) obtained by reacting the product with the acid monoanhydride (a4), the structure of the molecules is less likely to vary. Therefore, for example, a carboxyl group-containing resin (A1) having a weight average molecular weight in the range of 1000 to 5000 or having a specific acid value can be produced stably.

  Components other than the carboxyl group-containing resin (A1) in the photosensitive resin composition will be described.

  As described above, the photosensitive resin composition includes, for example, a carboxyl group-containing resin (A), an unsaturated compound (B) having at least one ethylenically unsaturated bond in one molecule, and a photopolymerization initiator (C). And an epoxy compound (D), and the carboxyl group-containing resin (A) contains a carboxyl group-containing resin (A1).

  The carboxyl group-containing resin (A) may contain only the carboxyl group-containing resin (A1), or a carboxyl group-containing resin other than the carboxyl group-containing resin (A1) (hereinafter also referred to as carboxyl group-containing resin (F)). May further be contained.

  The carboxyl group-containing resin (F) can contain, for example, a compound having a carboxyl group and not having photopolymerizability (hereinafter referred to as (F1) component). (F1) A component contains the polymer of the ethylenically unsaturated monomer containing the ethylenically unsaturated compound which has a carboxyl group, for example. The ethylenically unsaturated compound having a carboxyl group can contain compounds such as acrylic acid, methacrylic acid, and 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 and the like with a dibasic acid anhydride. The ethylenically unsaturated monomer is 2- (meth) acryloyloxyethyl phthalate, 2- (meth) acryloyloxyethyl-2-hydroxyethyl phthalate, linear or branched aliphatic or alicyclic (provided that It may further contain an ethylenically unsaturated compound having no carboxyl group, such as (meth) acrylic acid ester (which may partially have an unsaturated bond in the ring).

  The carboxyl group-containing resin (F) may contain a compound having a carboxyl group and an ethylenically unsaturated group (hereinafter referred to as (F2) component). Moreover, carboxyl group-containing resin (F) may contain only the (F2) component. The component (F2) includes, for example, an intermediate that is a reaction product of an epoxy compound (g1) having two or more epoxy groups in one molecule and an ethylenically unsaturated compound (g2), a polyvalent carboxylic acid and its anhydride. A resin (referred to as a first resin (g)) that is a reaction product with at least one compound (g3) selected from the group of substances. For example, the first resin (g) is obtained by adding the compound (g3) to an intermediate obtained by reacting the epoxy group in the epoxy compound (g1) with the carboxyl group in the ethylenically unsaturated compound (g2). Can be obtained. The epoxy compound (g1) can contain an appropriate epoxy resin such as a cresol novolac epoxy resin or a phenol novolac epoxy resin. The epoxy compound (g1) may contain a polymer of the ethylenically unsaturated compound (h). The ethylenically unsaturated compound (h) contains a compound (h1) having an epoxy group such as glycidyl (meth) acrylate, or further has no epoxy group such as 2- (meth) acryloyloxyethyl phthalate. Contains compound (h2). The ethylenically unsaturated compound (g2) preferably contains at least one of acrylic acid and methacrylic acid. The compound (g3) contains one or more compounds selected from the group consisting of polyvalent carboxylic acids such as phthalic acid, tetrahydrophthalic acid, and methyltetrahydrophthalic acid, and anhydrides of these polyvalent carboxylic acids. .

  The component (F2) is a resin (second resin) that 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. (I)) may be contained. The ethylenically unsaturated monomer may further contain an ethylenically unsaturated compound having no carboxyl group. The second resin (i) can be obtained by reacting an ethylenically unsaturated compound having an epoxy group with a part of the carboxyl group 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. Examples of the ethylenically unsaturated compound having no carboxyl group include 2- (meth) acryloyloxyethyl phthalate, 2- (meth) acryloyloxyethyl-2-hydroxyethyl phthalate, linear or branched aliphatic or oil It contains a compound such as a (meth) acrylic acid ester of a cyclic group (however, it may have some unsaturated bonds 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) or the carboxyl group-containing resin (A1) and the carboxyl group-containing resin (F). The carboxyl group-containing resin (A) preferably contains 30% by mass or more of the carboxyl group-containing resin (A1), more preferably 50% by mass or more, and still more preferably 100% by mass. In this case, the heat resistance and insulation reliability of the cured product of the photosensitive resin composition can be particularly improved. Moreover, the tackiness of the film | membrane formed from the photosensitive resin composition can fully be reduced. Furthermore, the developability by the alkaline aqueous solution of the photosensitive resin composition is securable.

  The unsaturated compound (B) can impart photocurability to the photosensitive resin composition. The unsaturated compound (B) is, for example, a monofunctional (meth) acrylate such as 2-hydroxyethyl (meth) acrylate; and diethylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) Acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ε-caprolactone modified pentaerythritol hexaacrylate, tricyclodecandi At least one compound selected from the group consisting of polyfunctional (meth) acrylates such as methanol di (meth) acrylate can be contained.

  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 the film formed from the photosensitive resin composition is exposed and developed 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. Phosphorus-containing unsaturated compounds include, for example, 2-methacryloyloxyethyl acid phosphate (as specific examples, product number light ester P-1M and light ester P-2M manufactured by Kyoeisha Chemical Co., Ltd.), 2-acryloyloxyethyl acid phosphate (As a specific example, product number light acrylate P-1A manufactured by Kyoeisha Chemical Co., Ltd.), diphenyl-2-methacryloyloxyethyl phosphate (as a specific example, product number MR-260 manufactured by Daihachi Kogyo Co., Ltd.), and Showa Polymer Co., Ltd. HFA series (part number HFA-6003 which is an addition reaction product of dipentaerystol hexaacrylate and HCA (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) as a specific example, and HFA-6007, caprolactone Product No. HFA-3003, HFA-6127, etc., which are addition reaction products of modified dipentaerystol hexaacrylate and HCA (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) It can contain at least one compound selected from the group.

  The unsaturated compound (B) may contain a prepolymer. The prepolymer is at least one selected from the group consisting of, for example, a prepolymer obtained by polymerizing a monomer having an ethylenically unsaturated bond and then adding an ethylenically unsaturated group, and oligo (meth) acrylate prepolymers These compounds can be contained. 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 At least one component selected from the group consisting of:

  The photopolymerization initiator (C) contains, for example, an acyl phosphine oxide photopolymerization initiator (C1). That is, the photosensitive resin composition contains, for example, an acyl phosphine oxide photopolymerization initiator (C1). In this case, although the photosensitive resin composition contains the carboxyl group-containing resin (A1), high sensitivity to ultraviolet rays can be imparted to the photosensitive resin composition. Moreover, generation | occurrence | production of the ion migration in the layer containing the hardened | cured material of the photosensitive resin composition is suppressed, and the insulation reliability of the same layer improves further.

  Further, the acyl phosphine oxide photopolymerization initiator (C1) is unlikely to inhibit the electrical insulation of the cured product. For this reason, by curing the photosensitive resin composition by exposure, a cured product having excellent electrical insulation can be obtained. This cured product can be used as, for example, a solder resist layer, a plating resist layer, an etching resist layer, or an interlayer insulating layer. Is preferred.

  Acylphosphine oxide photopolymerization initiator (C1) is, for example, monoacyl such as 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2,4,6-trimethylbenzoyl-ethyl-phenyl-phosphinate Phosphine oxide photopolymerization initiator, 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-dimethoxyben Yl) -2,4,4-trimethylpentylphosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,5-dimethylphenylphosphine oxide, bis- (2,4,6-trimethylbenzoyl) phenylphosphine Contains at least one component selected from the group consisting of bisacylphosphine oxide photopolymerization initiators such as fin oxide and (2,5,6-trimethylbenzoyl) -2,4,4-trimethylpentylphosphine oxide it can. 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, It is also preferred to contain only 4,6-trimethylbenzoyl-diphenyl-phosphine oxide.

  The photopolymerization initiator (C) preferably contains a hydroxyketone photopolymerization initiator (C2) in addition to the acylphosphine oxide photopolymerization initiator (C1). That is, the photosensitive resin composition preferably contains a hydroxyketone photopolymerization initiator (C2). In this case, higher photosensitivity can be imparted to the photosensitive resin composition as compared with the case where the hydroxyketone photopolymerization initiator (C2) is not contained. Thereby, when irradiating and hardening an ultraviolet-ray to the coating film formed from the photosensitive resin composition, it becomes possible to fully harden a coating film over the deep part from the surface. Examples of the hydroxyketone photopolymerization initiator (C2) include 1-hydroxy-cyclohexyl-phenyl-ketone, phenylglyoxyc acid methyl ester, and 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-propane-1- On and 2-hydroxy-2-methyl-1-phenyl-propan-1-one.

  The mass ratio of the acylphosphine oxide photopolymerization initiator (C1) and the hydroxyketone photopolymerization initiator (C2) is preferably in the range of 1: 0.01 to 1:10. In this case, the curability in the vicinity of the surface of the coating film formed from the photosensitive resin composition and the curability in the deep portion can be improved in a well-balanced manner.

  The photopolymerization initiator (C) also preferably contains bis (diethylamino) benzophenone (C3). That is, the photosensitive resin composition contains an acyl phosphine oxide photopolymerization initiator (C1) and bis (diethylamino) benzophenone (C3), or an acyl phosphine oxide photopolymerization initiator (C1), a hydroxyketone type. It is also preferable to contain a photopolymerization initiator (C2) and bis (diethylamino) benzophenone (C3). In this case, when developing after partially exposing the coating film formed from the photosensitive resin composition, since the hardening of the part which is not exposed is suppressed, resolution becomes especially high. For this reason, the hardened | cured material of the photosensitive resin composition of a very fine pattern can be formed. 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 provided in the interlayer insulating layer by a photolithography method (see FIG. 1), the small-diameter hole is formed. Precise and easy to form.

  The amount of bis (diethylamino) benzophenone (C3) relative to the acylphosphine oxide photopolymerization initiator (C1) is preferably in the range of 0.5 to 20% by mass. When the amount of bis (diethylamino) benzophenone (C3) with respect to the acylphosphine oxide photopolymerization initiator (C1) is 0.5% by mass or more, the resolution is particularly high. Further, when the amount of bis (diethylamino) benzophenone (C3) relative to the acylphosphine oxide-based photopolymerization initiator (C1) is 20% by mass or less, the electrical insulation of the cured product of the photosensitive resin composition is increased to bis (diethylamino). ) Benzophenone (C3) is difficult to inhibit.

  The photosensitive resin composition may further contain a known photopolymerization accelerator, sensitizer and the like. For example, the photosensitive resin composition includes benzoin and its alkyl ethers; acetophenones such as acetophenone and benzyldimethyl ketal; anthraquinones such as 2-methylanthraquinone; 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2- Thioxanthones such as isopropylthioxanthone, 4-isopropylthioxanthone and 2,4-diisopropylthioxanthone; benzophenones such as benzophenone and 4-benzoyl-4′-methyldiphenyl sulfide; xanthones such as 2,4-diisopropylxanthone; Α-hydroxyketones such as hydroxy-2-methyl-1-phenyl-propan-1-one; 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-propanone It can contain at least one component selected from the group consisting of compounds containing a nitrogen atom. The photosensitive resin composition includes known photopolymerization initiators (C) and tertiary amines such as p-dimethylbenzoic acid ethyl ester, p-dimethylaminobenzoic acid isoamyl ester, and 2-dimethylaminoethylbenzoate. You may contain a photoinitiator, a sensitizer, etc. The photosensitive resin composition may contain at least one of a photopolymerization initiator for visible light exposure and a photopolymerization initiator for near infrared exposure, if necessary. The photosensitive resin composition contains a photopolymerization initiator (C) and a coumarin derivative such as 7-diethylamino-4-methylcoumarin, which is a sensitizer for laser exposure, a carbocyanine dye system, a xanthene dye system, and the like. May be.

  The epoxy compound (D) can impart thermosetting properties to the photosensitive resin composition. The epoxy compound (D) preferably has at least two epoxy groups in one molecule. The epoxy compound (D) may be a solvent-insoluble epoxy compound or a general-purpose solvent-soluble epoxy compound. The epoxy compound (D) is a phenol novolac type epoxy resin (specifically, product number EPICLON N-775 manufactured by DIC Corporation), a cresol novolak type epoxy resin (specifically, product number EPICLON N-695 manufactured by DIC Corporation), bisphenol A. Novolac type epoxy resin (specifically, 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 (specifically, Mitsubishi Chemical Corporation) (Product number jER4004P manufactured by Co., Ltd.), bisphenol S type epoxy resin (specific example, product number EPICLON EXA-1514 manufactured by DIC Corporation), bisphenol AD type epoxy resin, biphenyl type epoxy resin (specific) As a product number YX4000 manufactured by Mitsubishi Chemical Co., Ltd.), biphenyl novolac type epoxy resin (specifically, product number NC-3000 manufactured by Nippon Kayaku Co., Ltd.), hydrogenated bisphenol A type epoxy resin (specifically manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) Product number ST-4000D), naphthalene type epoxy resin (specific examples: product numbers EPICLON HP-4032, EPICLON HP-4700, EPICLON HP-4770, manufactured by DIC Corporation), hydroquinone type epoxy resin (specific examples, manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) Product number YDC-1312), tertiary butyl catechol type epoxy resin (specifically, product number EPICLON HP-820 manufactured by DIC Corporation), dicyclopentadiene type epoxy resin (specific example, product number EPICLON H manufactured by DIC) -7200), adamantane type epoxy resin (part number ADAMANTATE X-E-201 manufactured by Idemitsu Kosan Co., Ltd.), bisphenol type epoxy resin (part number YSLV-80XY manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), biphenyl ether type epoxy Resin (part number YSLV-80DE manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), tetrakisphenolethane type epoxy resin (part number GTR-1800 manufactured by Nippon Kayaku Co., Ltd.) Epoxy resin having bisphenolfluorene skeleton (specific example As an example, an epoxy resin having a structure (S7), a rubbery core-shell polymer modified bisphenol A type epoxy resin (as a specific example, product number MX-156 manufactured by Kaneka Corporation), a rubbery core shell polymer modified bisphenol F type epoxy resin. As specific examples, product number MX-136 manufactured by Kaneka Co., Ltd., and special bifunctional epoxy resin (as specific examples, product numbers YL7175-500 and YL7175-1000 manufactured by Mitsubishi Chemical Corporation; product number EPICLON TSR manufactured by DIC Corporation) -960, EPICLON TER-601, EPICLON TSR-250-80BX, EPICLON 1650-75MPX, EPICLON EXA-4850, EPICLON EXA-4816, EPICLON EXA-4822, and EPICLON EXA-9726; It is preferable to contain one or more components selected from the group consisting of -120TE).

  The epoxy compound (D) preferably contains a crystalline epoxy resin. In this case, the developability of the photosensitive resin composition can be improved. The crystalline epoxy resin is an epoxy resin having a melting point. The crystalline epoxy resin is, for example, triglycidyl isocyanurate (1,3,5-tris (2,3-epoxypropyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H)- Trione), hydroquinone type crystalline epoxy resin (as a specific example, product name YDC-1312 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), biphenyl type crystalline epoxy resin (as a specific example, product number YX-4000 manufactured by Mitsubishi Chemical Corporation), diphenyl ether type Crystalline epoxy resin (part number YSLV-80DE manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), bisphenol type crystal epoxy resin (part number YSLV-80XY manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), tetrakisphenol ethane type crystallinity Epoxy resin (as a specific example, product number GTR-1800 manufactured by Nippon Kayaku Co., Ltd. It may contain at least one component selected from the group consisting of bisphenol fluorene type crystalline epoxy resin (epoxy resin having a structure (S7) as a specific example).

  The amount of the crystalline epoxy resin relative to the epoxy compound (D) is preferably in the range of 10 to 100% by mass, more preferably in the range of 30 to 100% by mass, and in the range of 35 to 100% by mass. More preferably, it is within. In this case, the thermosetting reaction between the carboxyl group-containing resin and the epoxy resin is suppressed in the process before the thermosetting of the photosensitive resin composition, and the developability can be improved.

  In particular, the crystalline epoxy resin preferably contains a crystalline epoxy resin having a melting point of 110 ° C. or lower. That is, the epoxy compound (D) preferably contains a crystalline epoxy resin 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. Crystalline epoxy resins having a melting point of 110 ° C. or lower are, for example, biphenyl type epoxy resins (specifically, product number YX4000 manufactured by Mitsubishi Chemical Corporation), biphenyl ether type epoxy resins (specifically, product number YSLV-80DE manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.). ), And at least one component selected from the group consisting of bisphenol type epoxy resins (specifically, Nippon Steel & Sumikin Chemicals product number YSLV-80XY).

  The epoxy compound (D) may contain triglycidyl isocyanurate. Triglycidyl isocyanurate is preferably a β-form having a structure in which three epoxy groups are bonded in the same direction with respect to the S-triazine ring skeleton, or the β-form and the S-triazine ring skeleton. On the other hand, it is preferable that one epoxy group is a mixture with an α-form having a structure in which the other two epoxy groups are bonded in different directions.

  It is also preferred that the crystalline epoxy resin contains a crystalline epoxy resin having a melting point of less than 100 ° C. That is, the epoxy compound (D) preferably contains a crystalline epoxy resin having a melting point of less than 100 ° C. In this case, the developability of the photosensitive resin composition can be further improved. In addition, a crystalline epoxy resin having a melting point of less than 100 ° C. is highly compatible with components and solvents other than the epoxy resin (D) in the photosensitive resin composition, so that it is dispersed in the photosensitive resin composition. Easy to homogenize. Furthermore, when the photosensitive resin composition contains a crystalline epoxy resin having a melting point of less than 100 ° C., crystallization hardly occurs even at a low temperature. For this reason, high storage stability can be provided to the photosensitive resin composition. Furthermore, since the crosslinking reaction between the carboxyl group and the epoxy group in the photosensitive resin composition is suppressed at a low temperature, the photosensitive resin composition has high storage stability while maintaining good developability. Can be granted.

  Crystalline epoxy resins having a melting point of less than 100 ° C. are, for example, biphenyl ether type epoxy resins (specifically, product number YSLV-80DE manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) and bisphenol type epoxy resins (specifically, product number YSLV manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.). -80XY), at least one component selected from the group consisting of epoxy resins having a bisphenolfluorene skeleton (an epoxy resin having the structure (S7) as a specific example) can be contained.

  When the epoxy compound (D) contains a crystalline epoxy resin having a melting point of less than 100 ° C., the equivalent of the epoxy group contained in the crystalline epoxy resin having a melting point of less than 100 ° C. is the carboxyl group contained in the carboxyl group-containing resin (A). It is preferably within a range of 0.2 to 2.0, more preferably within a range of 0.25 to 1.7, and within a range of 0.3 to 1.5 with respect to 1 equivalent. Further preferred.

  The epoxy compound (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. Examples of the phosphorus-containing epoxy resin include phosphoric acid-modified bisphenol F type epoxy resins (specific examples, product numbers EPICLON EXA-9726 and EPICLON EXA-9710 manufactured by DIC Corporation), and product number Epototo FX-305 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. Etc.

  The photosensitive resin composition may contain melamine. The photosensitive resin composition may contain a component (E) containing at least one of melamine and a melamine derivative. In this case, the adhesion between the cured product of the photosensitive resin composition and a metal such as copper is increased. For this reason, the photosensitive resin composition is particularly suitable as an insulating material for a printed wiring board. Moreover, the plating resistance of the cured product of the photosensitive resin composition, that is, the whitening resistance during the electroless nickel / gold plating process is improved.

  Melamine is 2,4,6-triamino-1,3,5-triazine and is generally available from commercially available compounds. The melamine derivative may be a compound having one triazine ring and an amino group in one molecule. Examples of melamine derivatives include guanamine; acetoguanamine; benzoguanamine; 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-4,6-diamino-S-triazine, 2-vinyl-4,6. -S-triazine derivatives such as diamino-S-triazine isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-S-triazine isocyanuric acid adduct; and melamine such as melamine-tetrahydrophthalate A reaction product with an acid anhydride is mentioned. Specific examples of the melamine derivative include Shikoku Kasei Kogyo Co., Ltd. product name VD-1, product name VD-2, and product name VD-3.

  The photosensitive resin composition may contain an organic solvent. The organic solvent is used for the purpose of liquefaction or varnishing of the photosensitive resin composition, viscosity adjustment, application property adjustment, film formation property adjustment, and the like.

  Organic solvents include, for example, linear, branched, secondary or polyhydric alcohols such as ethanol, propyl alcohol, isopropyl alcohol, hexanol and ethylene glycol; ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene and xylene Petroleum aromatic mixed solvents such as Swazol series (manufactured by Maruzen Petrochemical Co., Ltd.) and Solvesso series (manufactured by Exxon Chemical Co.); cellosolves such as cellosolve and butylcellosolve; Tolls; propylene glycol alkyl ethers such as propylene glycol methyl ether; polypropylene glycol alkyl ethers such as dipropylene glycol methyl ether; ethyl acetate, butyl acetate, cellosolve acetate, carb Acetic esters such Lumpur acetate; as well as containing at least one compound selected from the group consisting of dialkyl glycol ethers.

  The amount of the component in the photosensitive resin composition is 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) relative to the solid content of the photosensitive resin composition is preferably in the range of 5 to 85% by mass, more preferably in the range of 10 to 75% by mass, and 30 to 60%. If it is in the range of mass%, it is still more preferable.

  The amount of the unsaturated compound (B) relative to the carboxyl group-containing resin (A) is preferably in the range of 1 to 50% by mass, more preferably in the range of 10 to 45% by mass, and 21 to 40% by mass. If it is in the range, it is more preferable. In particular, when the amount of the unsaturated compound (B) relative to the carboxyl group-containing resin (A) is in the range of 21 to 40% by mass, the photosensitive resin composition is imparted with excellent photocurability while being imparted to the photosensitive resin composition. The developability of the product can be further improved, and the tackiness of the film formed from the photosensitive resin composition can be further reduced. That is, when the amount of the unsaturated compound (B) relative to the carboxyl group-containing resin (A) is 21% by mass or more, the developability of the photosensitive resin composition is improved while improving the photocurability of the photosensitive resin composition. Further improvement can be achieved. Moreover, the tackiness of the film | membrane formed from the photosensitive resin composition is further reduced as the quantity of the unsaturated compound (B) with respect to carboxyl group-containing resin (A) is 40 or less.

  The amount of the photopolymerization initiator (C) relative to the carboxyl group-containing resin (A) is preferably in the range of 0.1 to 30% by mass, and more preferably in the range of 1 to 25% by mass.

  Regarding the amount of the epoxy compound (D), the total equivalent of the epoxy groups contained in the epoxy compound (D) is 0.7 to 2.5 with respect to 1 equivalent of the carboxyl group contained in the carboxyl group-containing resin (A). Is preferably within the range of 0.7 to 2.3, more preferably within the range of 0.7 to 2.0.

  When the photosensitive resin composition contains melamine, the amount of melamine relative to the carboxyl group-containing resin (A) is preferably in the range of 0.1 to 10% by mass, and in the range of 0.5 to 5% by mass. If it is in, it is more preferable.

  When the photosensitive resin composition contains the component (E) containing at least one of melamine and melamine derivatives, the amount of the component (E) relative to the carboxyl group-containing resin (A) is 0.1 to 10 mass. %, Preferably in the range of 0.5 to 5% by mass.

  When the photosensitive resin composition contains an organic solvent, the amount of the organic solvent is such that when the coating film formed from the photosensitive resin composition is dried, the organic solvent is quickly volatilized and eliminated, that is, the organic solvent. It is preferable to adjust so that does not remain in the film. In particular, the amount of the organic solvent relative to the entire photosensitive resin composition is preferably in the range of 0 to 99.5% by mass, and more preferably in the range of 15 to 60% by mass. In addition, since the suitable ratio of an organic solvent changes with application methods etc., it is preferable to adjust a ratio suitably according to the application method.

  In addition, solid content is a total amount of all components remove | excluding volatile components, such as a solvent, from the photosensitive resin composition.

  As long as the effect of this embodiment is not impaired, the photosensitive resin composition may further contain components other than the said component.

  For example, the photosensitive resin composition may contain an inorganic filler. In this case, the curing shrinkage of the film formed from the photosensitive resin composition is reduced. The inorganic filler can contain, for example, at least one material selected from the group consisting of barium sulfate, crystalline silica, nanosilica, carbon nanotubes, talc, bentonite, aluminum hydroxide, magnesium hydroxide, and titanium oxide. You may whiten the photosensitive resin composition and its hardened | cured material by making an inorganic filler contain white materials, such as a titanium oxide and a zinc oxide. Although the ratio of the inorganic filler in the photosensitive resin composition is appropriately set, the amount of the inorganic filler relative to the carboxyl group-containing resin (A) is preferably in the range of 0 to 300% by mass.

  Photosensitive resin composition comprising tolylene diisocyanate, morpholine diisocyanate, isophorone diisocyanate and hexamethylene diisocyanate blocked isocyanates blocked with caprolactam, oxime, malonic acid ester, etc .; melamine resin, n-butylated melamine resin , Amino resins such as isobutylated melamine resin, butylated urea resin, butylated melamine urea cocondensation resin, benzoguanamine cocondensation resin; various other thermosetting resins; ultraviolet curable epoxy (meth) acrylate; bisphenol A type , Resins obtained by adding (meth) acrylic acid to phenolic novolac type, cresol novolac type, alicyclic type epoxy resins; and diallyl phthalate resin, phenoxy resin, urethane resin, fluorine resin, etc. It may contain at least one resin selected from the group consisting of a polymer compound.

  The photosensitive resin composition may contain a curing agent for curing the epoxy compound (D). Examples of the curing agent include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1- (2 Imidazole derivatives such as -cyanoethyl) -2-ethyl-4-methylimidazole; 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 hydrazide and sebacic acid hydrazide; phosphorus compounds such as triphenylphosphine; acid anhydrides; phenols; mercaptans; And It can contain at least one component selected from the group consisting um salt. Commercial products of these components include, for example, 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, 2P4MHZ (both trade names of imidazole compounds) manufactured by Shikoku Kasei Co., Ltd., U-CAT3503N, U manufactured by San Apro Co., Ltd. -CAT3502T (all are trade names of blocked isocyanate compounds of dimethylamine), DBU, DBN, U-CATSA102, U-CAT5002 (all are bicyclic amidine compounds and salts thereof).

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

  Photosensitive resin composition includes curing accelerator; colorant; copolymer such as silicone and acrylate; leveling agent; adhesion imparting agent such as silane coupling agent; thixotropic agent; thermal polymerization inhibitor; The composition may contain at least one component selected from the group consisting of a flame retardant, an antifoaming agent, an antioxidant, a surfactant, and a polymer dispersant.

  The content of the amine compound in the photosensitive resin composition is preferably as small as possible. If it does in this way, the electrical insulation of the layer which consists of hardened | cured material of the photosensitive resin composition will not be impaired easily. In particular, the amount of the amine compound relative to the carboxyl group-containing resin (A) is preferably 6% by mass or less, and more preferably 4% by mass or less.

  The raw material of the photosensitive resin composition as described above is blended, and the photosensitive resin composition can be prepared by kneading by a known kneading method using, for example, a three roll, ball mill, sand mill or the like. In the case where the raw material of the photosensitive resin composition contains a liquid component, a low viscosity component, etc., the 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, among the components of the photosensitive resin composition, the unsaturated compound (B), a part of the organic solvent, and the thermosetting component are mixed in advance and dispersed to prepare the first agent. The second agent may be prepared by mixing and dispersing the remainder of the components of the conductive resin composition. In this case, it is possible to prepare a mixed solution by mixing the necessary amount of the first agent and the second agent in a timely manner and curing the mixed solution to obtain a cured product.

  The photosensitive resin composition according to the present embodiment is suitable for an electrically insulating material for a printed wiring board. In particular, the photosensitive resin composition is suitable for materials for electrically insulating layers such as a solder resist layer, a plating resist layer, an etching resist layer, and an interlayer insulating layer.

  The photosensitive resin composition according to the present embodiment preferably has such a property that even a 25 μm thick film can be developed with an aqueous sodium carbonate solution. In this case, since it is possible to produce a sufficiently thick electrically insulating layer from the photosensitive resin composition by photolithography, the photosensitive resin composition can be used as an interlayer insulating layer, a solder resist layer, etc. in a printed wiring board. It can be widely applied to fabricate. Of course, it is also possible to produce an electrically insulating layer having a thickness of less than 25 μm from the photosensitive resin composition.

Whether or not a 25 μm thick film can be developed with an aqueous sodium carbonate solution can be confirmed by the following method. A wet paint film is formed by applying the photosensitive resin composition on a suitable substrate, and this wet paint film is heated at 80 ° C. for 40 minutes to form a film having a thickness of 25 μm. The film is exposed by irradiating the film with ultraviolet rays under a condition of 500 mJ / cm ² with a negative mask having an exposed part that transmits ultraviolet rays and a non-exposed part that blocks ultraviolet rays directly applied. After the exposure, a 1% Na ₂ CO ₃ aqueous solution at 30 ° C. is jetted for 90 seconds at a jetting pressure of 0.2 MPa, and then pure water is jetted for 90 seconds at a jetting pressure of 0.2 MPa. As a result of observing the film after this treatment, it can be determined that the film having a thickness of 25 μm can be developed with an aqueous sodium carbonate solution when a portion corresponding to the non-exposed portion of the film is removed and no residue is observed.

  Below, an example of the method of manufacturing a printed wiring board provided with the interlayer insulation layer formed from the photosensitive resin composition by this embodiment is demonstrated with reference to FIG. 1A to FIG. 1E. In this method, a through hole is formed in the interlayer insulating layer by photolithography.

  First, the core material 1 is prepared as shown in FIG. 1A. The core material 1 includes, for example, at least one insulating layer 2 and at least one conductor wiring 3. The conductor wiring 3 provided on one surface of the core material 1 is hereinafter referred to as a first conductor wiring 3. As shown in FIG. 1B, a film 4 is formed on one surface of the core material 1 from a photosensitive resin composition. Examples of the method for forming the film 4 include a coating method and a dry film method.

  In the coating method, for example, a photosensitive resin composition is coated on 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 known methods such as dipping, spraying, spin coating, roll coating, curtain coating, and screen printing. Subsequently, in order to volatilize the organic solvent in the photosensitive resin composition, for example, the wet coating film is dried at a temperature in the range of 60 to 120 ° C., whereby the coating film 4 can be obtained.

  In the dry film method, a photosensitive resin composition is first applied on an appropriate support made of polyester or the like and then dried to form a dry film that is a dried product of the photosensitive resin composition on the support. To do. Thereby, a laminated body provided with a dry film and the support body which supports a dry film is obtained. After the dry film in this laminate is overlaid on the core material 1, pressure is applied to the dry film and the core material 1, and then the support is peeled from the dry film, so that the dry film is placed on the core material 1 from the support. Transfer to Thereby, the coating 4 made of a dry film is provided on the core material 1.

  By exposing the film 4, the film 4 is partially cured as shown in FIG. 1C. For this purpose, for example, a negative mask is applied to the film 4 and then the film 4 is irradiated with ultraviolet rays. The negative mask includes an exposure part that transmits ultraviolet light and a non-exposure part that blocks ultraviolet light, and the non-exposure part 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. The ultraviolet light source is selected from the group consisting of, for example, a chemical lamp, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a xenon lamp, and a metal halide lamp.

  The exposure method may be a method other than a method using a negative mask. For example, the film 4 may be exposed by a direct drawing method in which only the portion of the film 4 to be exposed is irradiated with ultraviolet rays emitted from a light source. The light source applied to the direct drawing method is, for example, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, g line (436 nm), h line (405 nm), i line (365 nm), and g line, h line and i line. It is selected from the group consisting of two or more kinds of combinations.

  In the dry film method, the film 4 is exposed by irradiating the film 4 made of the dry film with ultraviolet rays through the support without peeling the support after the dry film in the laminate is stacked on the core material 1. Subsequently, the support may be peeled off from the film 4 before development processing.

  Subsequently, the coating 4 is developed to remove the unexposed portion 5 of the coating 4 shown in FIG. 1C, whereby the hole 6 is formed at the position where the through hole 10 is formed as shown in FIG. 1D. Is provided. In the development process, an appropriate developer according to the composition of the photosensitive resin composition can be used. 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, tetramethyl ammonium hydroxide and water. It contains at least one component selected from the group consisting of lithium oxide. The solvent in the alkaline aqueous solution may be water alone 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 work environment and reduce the burden of waste disposal.

  Subsequently, the coating 4 is cured by heating. The heating conditions are, for example, within a heating temperature range of 120 to 200 ° C. and within a heating time range of 30 to 120 minutes. When the film 4 is thermally cured in this manner, the performance of the interlayer insulating layer 7 such as strength, hardness, and chemical resistance is improved.

  If necessary, the coating 4 may be further irradiated with ultraviolet rays before or after heating. In this case, photocuring of the film 4 can be further advanced.

  As described above, the interlayer insulating layer 7 made of a cured product of the photosensitive resin composition is provided on the core material 1. The second conductor wiring 8 and the hole plating 9 can be provided on the interlayer insulating layer 7 by a known method such as an additive method. As a result, as shown in FIG. 1E, the first conductor wiring 3, the second conductor wiring 8, the interlayer insulating layer 7 interposed between the first conductor wiring 3 and the second conductor wiring 8, and the first conductor wiring A printed wiring board 11 having a through hole 10 for electrically connecting the first conductor wiring 3 and the second conductor wiring 8 is obtained. In FIG. 1E, the hole plating 9 has a cylindrical shape that covers the inner surface of the hole 6, but the entire inner side of the hole 6 may be filled with the hole plating 9.

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

  First, a core material is prepared. The core material includes, for example, at least one insulating layer and at least one conductor wiring. A film is formed from the photosensitive resin composition on the surface of the core material where the conductor wiring is provided. Examples of the method for forming the film include a coating method and a dry film method. As the coating method and the dry film method, the same method as that for forming the interlayer insulating layer can be employed. The film is partially cured by exposure. The exposure method can be the same as the method for forming the interlayer insulating layer. Subsequently, the film is subjected to a development process to remove the unexposed part of the film, whereby the exposed part of the film remains on the core material. Subsequently, the coating on the core material is heated and cured. The developing method and the heating method can be the same as the method for forming the interlayer insulating layer. If necessary, the film may be further irradiated with ultraviolet rays before or after heating. In this case, photocuring of the film can be further advanced.

  By the above, the soldering resist layer which consists of hardened | cured material of the photosensitive resin composition is provided on a core material. Thereby, a printed wiring board provided with the core material provided with an insulating layer and the conductor wiring on it, and the soldering resist layer which partially covers the surface in which the conductor wiring in a core material is provided is obtained.

(1) Examples A-1 to A-7 and Comparative Examples B-1 to B-2
Examples A-1 to A-7 and Comparative Examples B-1 to B-2, which are 65% by mass solutions of carboxyl group-containing resins, were synthesized as follows.

  In the four-necked flask equipped with a reflux condenser, thermometer, air blowing tube and stirrer, the raw material components shown in the “raw material components” column of the “first reaction” column in Table 1 are added, and these are air bubbled. The mixture was prepared by stirring under. The mixture was heated at the reaction temperature and reaction time shown in the “Reaction Conditions” column of the “First Reaction” column while stirring under air bubbling in a four-necked flask. This prepared an intermediate solution.

  Subsequently, the raw material components shown in the “raw material component” column of the “second reaction” column of Table 1 are added to the intermediate solution in the four-necked flask, and the solution in the four-necked flask is stirred under air bubbling. While heating, the reaction was carried out at the reaction temperature and reaction time shown in the “Reaction Conditions (1)” column of the “Second Reaction” column. Subsequently, in the case of Example A-5, the reaction temperature and reaction time indicated in the “Reaction Conditions (2)” column of the “Second Reaction” column are being stirred while the solution in the four-necked flask is stirred under air bubbling. Heated. This obtained a 65 mass% solution of carboxyl group-containing resin. The weight average molecular weight and acid value of the carboxyl group-containing resin are as shown in Table 1.

In addition, the epoxy resin 1 in Table 1 is a bisphenolfluorene type epoxy resin having an epoxy equivalent of 252 in which R _{1 to} R ₈ are all hydrogen, and the epoxy resin 2 is represented by the formula (2). And R _{1 to} R ₈ are all bisphenolfluorene type epoxy resins having an epoxy equivalent of 250, which is hydrogen.

(2) Preparation of photosensitive resin composition Examples 1 to 9 and Comparative Examples 1 and 2 as photosensitive resin compositions were prepared as follows.

The components shown in the “Composition” column of Table 2 below were kneaded with three rolls, and these components were stirred and mixed in a flask to obtain a photosensitive resin composition. Details of the components are as follows.
Unsaturated compound A: dipentaerythritol hexaacrylate modified with 2 caprolactones per molecule, manufactured by Nippon Kayaku Co., Ltd., product number KAYARAD DPCA-20.
Unsaturated compound B: trimethylolpropane triacrylate.
Photopolymerization initiator A: 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, manufactured by BASF, product number Irgacure TPO.
Photopolymerization initiator B: 1-hydroxy-cyclohexyl-phenyl-ketone, manufactured by BASF, product number Irgacure 184
Photopolymerization initiator C: 4,4′-bis (diethylamino) benzophenone
Epoxy resin A: Biphenyl type crystalline epoxy resin, manufactured by Mitsubishi Chemical Corporation, product number YX4000. Melting point 105 ° C.
Epoxy resin solution B: A solution having a solid content concentration of 75% by mass prepared by dissolving a cresol novolac type epoxy resin (manufactured by DIC Corporation, product number EPICLON N-695) in diethylene glycol monoethyl ether acetate.
Epoxy resin solution C: a solution having a solid content concentration of 90% by mass, prepared by dissolving a long-chain carbon chain-containing bisphenol A type epoxy resin (manufactured by DIC Corporation, part number Epicron EXA-4816) in diethylene glycol monoethyl ether acetate .
Melamine: manufactured by Nissan Chemical Industries, Ltd., fine melamine.
Antioxidant: A hindered phenol antioxidant, manufactured by BASF, product number IRGANOX 1010.
Blue pigment: phthalocyanine blue.
Yellow pigment: 1,1 ′-[(6-phenyl-1,3,5-triazine-2,4-diyl) bis (imino)] bis (9,10-anthracenedione).
Barium sulfate: manufactured by Sakai Chemical Industry Co., Ltd., product number Variace B31.
-Talc: Nippon Talc Co., Ltd. product number SG-2000.
Bentonite: manufactured by Leox, part number Benton SD-2
Antifoaming agent: manufactured by Shin-Etsu Silicone Co., Ltd., product number KS-66.
-Rheology control agent: Product number BYK-430 manufactured by Big Chemie Japan Co., Ltd.
Solvent A: Aromatic mixed solvent (petroleum naphtha), manufactured by Maruzen Petrochemical Co., Ltd., product number Swazol 1500.
Solvent B: diethylene glycol monoethyl ether acetate.
Solvent C: methyl ethyl ketone.

(3) Preparation of test piece About Examples 1-8 and Comparative Examples 1-2, the test piece was produced as follows.

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 50 μm / 50 μm was formed as a conductor wiring on this glass epoxy copper clad laminate by a subtractive method, thereby obtaining a core material. The coating film was formed by apply | coating the photosensitive resin composition to one whole surface of this core material with the screen printing method. This coating film was heated at 80 ° C. for 40 minutes and pre-dried to form a coating film having a thickness of 25 μm. In the case where Examples 1 to 7 and Comparative Examples 1 and 2 are used for the film through the negative mask with a negative mask having a circular non-exposed portion having a diameter of 40 μm and 60 μm directly applied to this film, 500 mJ / cm ^When Example 8 was used under the condition ² , the ultraviolet ray was irradiated under the condition of 300 mJ / cm ² . The exposed film was developed. In the development process, a 1% Na ₂ CO ₃ aqueous solution at 30 ° C. was sprayed onto the film for 90 seconds at a spray pressure of 0.2 MPa. Subsequently, the coating film was washed by spraying pure water at a spray pressure of 0.2 MPa for 90 seconds. Thereby, the part which was not exposed in a film | membrane was removed, and the hole was formed. This film was heated at 160 ° C. for 60 minutes, and then irradiated with ultraviolet rays under the condition of 1000 mJ / cm ² . Thereby, the layer which consists of hardened | cured material of the photosensitive resin composition was formed on the core material. As a result, a test piece was obtained.

  About Example 9, the test piece was produced as follows.

  The photosensitive resin composition was coated on a polyethylene terephthalate film with an applicator and then dried by heating at 95 ° C. for 25 minutes to form a dry film having a thickness of 25 μm on the film.

  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 50 μm / 50 μm was formed as a conductor wiring on this glass epoxy copper clad laminate by a subtractive method, thereby obtaining a core material. A dry film was laminated on the core material by heating with a vacuum laminator, and the dry film was laminated on the entire surface of the core material. The conditions for heat lamination are 0.5 MPa, 80 ° C., and 1 minute. As a result, a 25 μm-thick film made of a dry film was formed on the core material. This film was subjected to exposure, development and ultraviolet irradiation treatment under the same conditions as in Example 8. In addition, the film made from a polyethylene terephthalate was peeled from the dry film (coating) after exposure and before development. Thereby, the layer which consists of hardened | cured material of the photosensitive resin composition (it can also be said to be hardened | cured material of a dry film) was formed on the core material. As a result, a test piece was obtained.

(4) Evaluation test (4-1) Tackiness About Examples 1-8 and Comparative Examples 1-2, the degree of tackiness of the film when removing the negative mask from the film after exposure of the film during test piece production, Evaluation was performed as follows.
A: Resistance is not felt when removing the negative mask from the film, and no sticking marks are observed on the film after the negative mask is removed.
B: Resistance was felt when the negative mask was removed from the film, and sticking marks were observed on the film after the negative mask was removed.
C: It was difficult to remove the negative mask from the film, and the film was damaged when the negative mask was forcibly removed.

(4-2) Developability About Examples 1-8 and Comparative Examples 1-2, the wet paint film was formed by apply | coating the photosensitive resin composition to the whole surface of the printed wiring board by the screen printing method. This wet coating film was heated at 80 ° C. for 40 minutes or 60 minutes to form a film having a thickness of 25 μm. This film was developed without exposure. In the development process, a 1% Na ₂ CO ₃ aqueous solution at 30 ° C. was sprayed for 90 seconds at an injection pressure of 0.2 MPa, and then pure water was sprayed for 90 seconds at an injection pressure of 0.2 MPa. The printed wiring board after the treatment was observed, and the result was evaluated as follows.
A: The film was completely removed regardless of whether the heating time of the wet coating film was 40 minutes or 60 minutes.
B: When the heating time of the wet coating film was 40 minutes, all the coating film was removed, but at 60 minutes, a part of the coating film remained on the printed wiring board.
C: A part of the film remained on the printed wiring board regardless of whether the heating time of the wet coating film was 40 minutes or 60 minutes.

  In addition, for Comparative Example 1 in which the developability evaluation is C, the following evaluations (4-3) to (4-8) are not performed. Moreover, in the case of Example 9, since the membrane | film | coat was formed from the dry film, developability evaluation was not performed. In the case of Example 9, development was possible without problems in the development process after exposure.

(4-3) Resolution About Examples 1-9 and Comparative Example 2, the holes formed in the layer made of the cured product in the test piece were observed, and the results were evaluated as follows.
A: A hole corresponding to a non-exposed portion having a diameter of 40 μm and a hole corresponding to a non-exposed portion having a diameter of 60 μm are formed.
B: A hole corresponding to a non-exposed portion having a diameter of 60 μm is formed, but a hole corresponding to a non-exposed portion having a diameter of 40 μm is not formed.
C: Neither a hole corresponding to a non-exposed portion having a diameter of 40 μm or a hole corresponding to a non-exposed portion having a diameter of 60 μm is formed.

(4-4) Solder heat resistance For Examples 1 to 9 and Comparative Example 2, after applying a water-soluble flux (product number LONCO 3355-11, manufactured by London Chemical Co., Ltd.) to the test piece, It was immersed in a molten solder bath for 10 seconds and subsequently washed with water. The appearance of the solder resist layer in the test piece after repeating this series of operations three times was observed and evaluated according to the following evaluation criteria.
A: No abnormality is observed.
B: Discoloration of the solder resist layer is slightly observed.
C: A large discoloration is observed in the solder resist layer. Or peeling of a soldering resist layer is seen.

(4-5) Plating resistance For Examples 1 to 9 and Comparative Example 2, a nickel plating layer was formed on a portion of the conductor wiring of the test piece exposed to the outside using a commercially available electroless nickel plating bath. Then, a gold plating layer was formed using a commercially available electroless gold plating bath. This formed the metal layer which consists of a nickel plating layer and a gold plating layer. The layer and metal layer which consisted of hardened | cured material were observed visually. Moreover, the cellophane adhesive tape peeling test was done with respect to the layer which consists of hardened | cured material. The results were evaluated as follows.
A: No abnormality was observed in the appearance of the layer made of the cured product and the metal layer, and peeling of the layer made of the cured product by the cellophane adhesive tape peeling test did not occur.
B: Although discoloration was recognized in the layer which consists of hardened | cured materials, peeling of the layer which consists of hardened | cured materials by the cellophane adhesive tape peeling test did not arise.
C: Lifting of the layer made of the cured product was observed, and peeling of the layer made of the cured product by the cellophane adhesive tape peeling test occurred.

(4-6) Insulation between lines For Examples 1 to 9 and Comparative Example 2, while applying a DC 30 V bias voltage to the conductor wiring (comb electrode) in the test piece, the test piece was 121 ° C., 97% R.D. H. The test environment was exposed for 150 hours. The electrical resistance value between the comb-type electrodes of the cured product layer in this test environment was constantly measured, and the result was evaluated according to the following evaluation criteria.
A: The electric resistance value was constantly maintained at 10 ⁶ Ω or more until 150 hours passed from the start of the test.
B: The electric resistance value was constantly maintained at 10 ⁶ Ω or more until 120 hours passed from the start of the test, but the electric resistance value was less than 10 ⁶ Ω before 150 hours passed from the start of the test.
C: The electric resistance value was less than 10 ⁶ Ω before 120 hours passed from the start of the test.

(4-7) Interlayer insulation About Examples 1-9 and Comparative Example 2, the conductive tape was affixed on the layer which consists of hardened | cured material in a test piece. While applying a bias voltage of DC 100 V to the conductive tape, the test piece was placed at 121 ° C. and 97% R.D. H. The test environment was exposed for 50 hours. The electrical resistance value between the conductive wiring of the layer made of the cured product and the conductive tape in this test environment was constantly measured, and the result was evaluated according to the following evaluation criteria.
A: The electric resistance value was constantly maintained at 10 ⁶ Ω or more until 50 hours passed from the start of the test.
B: The electric resistance value was always maintained at 10 ⁶ Ω or more until 40 hours passed from the start of the test, but the electric resistance value became less than 10 ⁶ Ω before 50 hours passed from the start of the test.
C: The electric resistance value was less than 10 ⁶ Ω before 40 hours passed from the start of the test.

(4-8) PCT
For Examples 1-9 and Comparative Example 2, the test piece was 121 ° C., 100% R.D. H. After being allowed to stand for 100 hours in this environment, the appearance of the layer made of the cured product was evaluated according to the following evaluation criteria.
A: No abnormality was found in the layer made of the cured product.
B: Discoloration was observed in the layer made of the cured product.
C: A large discoloration was observed in the layer made of the cured product, and partial swelling occurred.

Claims (13)

An intermediate of a reaction product of an epoxy compound (a1), an unsaturated group-containing monocarboxylic acid (a2) and a polyvalent carboxylic acid (a6), and an acid anhydride,
The epoxy compound (a1) has a bisphenolfluorene skeleton,
The bisphenol fluorene skeleton is represented by the following formula (1):
In the following formula (1), R _{1 to} R ₈ are each independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or halogen.
Carboxyl group-containing resin.
The total of carboxyl groups in the unsaturated group-containing monocarboxylic acid (a2) with respect to 1 mol of the epoxy group of the epoxy compound (a1) is in the range of 0.5 to 0.95 mol.
The carboxyl group-containing resin according to claim 1. The polyvalent carboxylic acid (a6) contains a dicarboxylic acid.
The carboxyl group-containing resin according to claim 1 or 2. The acid anhydride contains an acid dianhydride (a3).
The carboxyl group-containing resin according to any one of claims 1 to 3. The weight average molecular weight is in the range of 1000-5000,
The carboxyl group-containing resin according to any one of claims 1 to 4. The solid content acid value is in the range of 60 to 140 mg KOH / g.
The carboxyl group-containing resin according to any one of claims 1 to 5. A carboxyl group-containing resin (A);
An unsaturated compound (B) having at least one ethylenically unsaturated bond in one molecule;
A photopolymerization initiator (C);
Containing an epoxy compound (D),
The carboxyl group-containing resin (A) contains the carboxyl group-containing resin according to any one of claims 1 to 6,
Photosensitive resin composition. When formed into a film having a thickness of 25 μm, the film can be developed with an aqueous sodium carbonate solution.
The photosensitive resin composition of Claim 7. The unsaturated compound (B) contains a compound having three unsaturated bonds in one molecule.
The photosensitive resin composition of Claim 7 or 8. Including a dry product of the photosensitive resin composition according to any one of claims 7 to 9,
Dry film. An interlayer insulating layer containing a cured product of the photosensitive resin composition according to any one of claims 7 to 9,
Printed wiring board. A solder resist layer comprising a cured product of the photosensitive resin composition according to any one of claims 7 to 9,
Printed wiring board. In the following formula (1), R _{1 to} R ₈ are each independently an epoxy compound (a1) having a bisphenolfluorene skeleton that is hydrogen, an alkyl group having 1 to 5 carbon atoms, or a halogen, and an unsaturated group-containing mono Carboxyl group-containing resin that synthesizes carboxyl group-containing resin (A1) by reacting carboxylic acid (a2) and polyvalent carboxylic acid (a6), and reacting the resulting intermediate with an acid anhydride Manufacturing method.