TW201726759A - Dry film layered product - Google Patents

Abstract

A dry film laminated body (15) relating to the present invention is provided with a base film (12), a dry film (13), and a cover film (14), which are laminated in this order. The base film (12) is a polyethylene terephthalate film, the dry film (13) contains a carboxyl group-containing resin (A) and a crystalline epoxy resin (B1). The cover film (14) is an oriented polypropylene film.

Description

Dry film laminate

The present invention relates to a dry film laminate.

In the past, various electrically insulating resin compositions have been used for forming an electrically insulating layer such as a solder resist layer, a plating resist layer, an etch resist layer, and an interlayer insulating layer of a printed wiring board. Such a resin composition is, for example, a resin composition containing a carboxyl group-containing resin. In addition, in order to impart thermosetting property to the resin composition, an epoxy resin is contained (refer to Japanese Patent No. 4508929).

The resin composition is often stored in the form of a dry film. The dry film is generally formed by coating a resin composition or the like on a base film. A dry film is formed on the base film by coating a resin composition or the like on the base film. A cover film is pressed onto the dry film to obtain a dry film laminate. This dry film laminate is stored, for example, in a roll shape.

However, during the storage of the dry film laminate, epoxy resin may be deposited between the outer surface of the base film and the outer surface of the cover film. Therefore, the composition of the dry film changes, and there is a problem in the storage stability of the dry film.

Further, the epoxy resin deposited from the dry film laminate may become a powder and adhere to the dry film. Therefore, when a dry film laminate is used in a clean room requiring particularly high pollution control, there is also a problem that the powder falls from the dry film laminate to contaminate the clean room.

An object of the present invention is to provide a dry film laminate which can suppress the precipitation of an epoxy resin on the outer surface of a dry film laminate and the formation of a powder composed of an epoxy resin.

A dry film laminate according to one aspect of the present invention, comprising: a base film, a dry film, and a cover film, wherein the base film is a polyethylene terephthalate film, the dry film The carboxyl group-containing resin (A) and the crystalline epoxy resin (B1) are contained, and the cover film is an extended polypropylene film.

According to one aspect of the present invention, it is possible to suppress the case where the epoxy resin is deposited on the outer surface of the dry film laminate and the powder composed of the epoxy resin.

Hereinafter, one embodiment of the present invention will be described. In the following description, "(meth)acrylic acid" means at least one of "acrylic acid" and "methacrylic acid". For example, (meth) acrylate means at least one of methacrylate and acrylate.

As shown in Fig. 1, the dry film laminate 15 of the present embodiment includes a base film 12, a dry film 13, and a cover film 14, and the films are sequentially laminated. The base film 12 is a polyethylene terephthalate film. The dry film 13 contains a carboxyl group-containing resin (A) and an epoxy compound (B), and the epoxy compound (B) contains a crystalline epoxy compound (B1). That is, the carboxyl group-containing resin (A) and the crystalline epoxy compound (B1) are contained, and the cover film 14 is an extended polypropylene film.

The dry film 13 has thermosetting property by containing a carboxyl group-containing resin (A) and a crystalline epoxy resin (B).

Conventionally, a cover film in a dry film laminate is generally a polyethylene film which is easily peeled off from a dry film. However, the inventors have found that, in particular, when a plurality of films contain a crystalline epoxy resin, the crystalline epoxy resin in the dry film penetrates the polyethylene film and is deposited on the outer surface of the dry film laminate.

Further, the inventors of the present invention have intensively studied and found that the above problem can be solved by applying the stretched polypropylene film as the cover film 14.

The stretched polypropylene film may be any of a uniaxially stretched polypropylene film and a biaxially stretched polypropylene film, preferably a biaxially stretched polypropylene film.

If the cover film 14 is an extended polypropylene film, the cover film 14 is less likely to penetrate the crystalline epoxy resin. Therefore, the precipitation of the epoxy resin on the outer surface of the dry film laminate 15 is suppressed, whereby the composition change of the dry film 13 can be suppressed. Thereby, the storage stability of the dry film laminate 15 is improved. Moreover, when the precipitation of the epoxy resin is suppressed in this manner, it is possible to suppress the occurrence of the powder composed of the epoxy resin on the outer surface of the dry film laminate 15 . Moreover, good peelability between the cover film 14 and the dry film 13 can be ensured.

Hereinafter, the components contained in the dry film 13 of the present embodiment will be specifically described.

First, the carboxyl group-containing resin (A) will be specifically described.

The carboxyl group-containing resin (A) may be any resin as long as it is a resin having a carboxyl group.

The carboxyl group-containing resin (A) is preferably a reaction product containing a polyol compound and a polyvalent carboxylic acid.

The polyol compound may be any compound having two or more hydroxyl groups. The polyol compound includes, for example, an addition reaction product of an epoxy resin having two or more epoxy groups and a carboxylic acid. This addition reactant has a hydroxyl group produced by an addition reaction of an epoxy group in an epoxy resin with a carboxyl group in a carboxylic acid.

The polycarboxylic acid is, for example, at least one of a polybasic acid and a polybasic acid anhydride. The polycarboxylic acid may contain, for example, at least one compound selected from the group consisting of polycarboxylic acids such as phthalic acid, tetrahydrophthalic acid, and methyl phthalic acid; and these polycarboxylic acids Acid anhydride.

The weight average molecular weight of the reactant of the polyol compound and the polycarboxylic acid is preferably in the range of from 700 to 40,000. When the weight average molecular weight is 700 or more, the viscosity of the dry film 13 is further suppressed, and the insulation reliability and plating resistance of the cured product can be further improved. Moreover, when the weight average molecular weight is 40,000 or less, the developability of the dry film 13 based on the alkaline aqueous solution is particularly improved. Further, the weight average molecular weight was calculated from the measurement results of the molecular weight measured under the following conditions by gel permeation chromatography. GPC device: manufactured by Showa Denko, trade name: SHODEX SYSTEM 11; column: SHODEX KF-800P, KF-005, KF-003, KF-001 4 tubes in series; mobile phase: tetrahydrofuran (THF); flow: 1ml /min; column temperature: 45 ° C; detector: refractive index (RI) detector; conversion: polystyrene.

The acid value of the reactant of the polyol compound and the polycarboxylic acid is preferably in the range of 50 to 200 mgKOH/g. At this time, the developability of the dry film 13 is particularly improved. The acid value is more preferably in the range of 60 to 140 mgKOH/g, more preferably in the range of 80 to 135 mgKOH/g, and particularly preferably in the range of 90 to 130 mgKOH/g.

The reactant of the polyol compound and the polyvalent carboxylic acid preferably contains, for example, a carboxyl group-containing resin (A1) having a bisphenol fluorene skeleton. That is, the carboxyl group-containing resin (A) preferably contains a carboxyl group-containing resin (A1). At this time, it is possible to impart high heat resistance and plating resistance to the cured product of the dry film 13 . The carboxyl group-containing resin (A1) is, for example, a reaction product of an intermediate with an acid anhydride obtained by reacting an epoxy compound (a1) with an unsaturated group-containing carboxylic acid (a2). The epoxy compound (a1) has a bisphenol fluorene skeleton, and the bisphenol fluorene skeleton is represented by the following formula (1), and in the formula (1), R ₁ to R ₈ are each independently hydrogen and have a carbon number of 1 to 5. Alkyl, or halogen.

The carboxyl group-containing resin (A1) is synthesized by reacting an intermediate with an acid anhydride obtained by reacting an epoxy compound (a1) with an unsaturated group-containing carboxylic acid (a2).

R ₁ to R ₈ in the formula (1) may each be hydrogen or may be an alkyl group having 1 to 5 carbon atoms or a halogen. The reason is that even if the hydrogen in the aromatic ring is replaced by a low molecular weight alkyl group or a halogen, the physical properties of the carboxyl group-containing resin (A1) are not adversely affected, and the carboxyl group-containing resin (A1) is sometimes promoted. The heat resistance or flame retardancy of the cured product of the photosensitive resin composition.

The carboxyl group-containing resin (A1) is more specifically described. In order to synthesize the carboxyl group-containing resin (A1), at least a part of the epoxy group (refer to the formula (2)) of the epoxy compound (a1) is first reacted with the unsaturated group-containing carboxylic acid (a2) to synthesize an intermediate. The intermediate has a structure (S3) represented by the following formula (3) which is produced by a ring-opening addition reaction of an epoxy group with an unsaturated group-containing carboxylic acid (a2). That is, the intermediate has a secondary hydroxyl group in the structure (S3) which is produced by a ring-opening addition reaction of an epoxy group with an unsaturated group-containing carboxylic acid (a2). In the formula (3), A is an unsaturated group-containing carboxylic acid residue.

The secondary hydroxyl group in the intermediate is then reacted with an anhydride. Thereby, the carboxyl group-containing resin (A1) can be synthesized.

The acid anhydride may contain at least one of acid dianhydride (a3) and acid monoanhydride (a4). When the acid anhydride contains the acid monoanhydride (a4), the carboxyl group-containing resin (A1) has a bisphenol fluorene skeleton (S1) represented by the formula (1) and a structure (S4) represented by the following formula (4).

The structure (S4) is produced by reacting a secondary hydroxyl group in the structure (S3) of the intermediate with an acid anhydride group in the acid monoanhydride (a4). In the formula (4), A is an unsaturated group-containing carboxylic acid residue, and B is an acid mono-anhydride residue.

When the acid anhydride contains the acid dianhydride (a3), the carboxyl group-containing resin (A1) has a bisphenol fluorene skeleton (S1) and a structure (S5) represented by the following formula (5).

The structure (S5) is produced by reacting two acid anhydride groups in the acid dianhydride (a3) with two secondary hydroxyl groups in the intermediate. That is, the structure (S5) is produced by crosslinking two secondary hydroxyl groups with each other by acid dianhydride (a3). Furthermore, there may be a case where two secondary hydroxyl groups present in one molecule of the intermediate are cross-linked to each other, and two secondary hydroxyl groups existing in the intermediate of two molecules respectively The situation of being cross-linked. If two secondary hydroxyl groups respectively present in the intermediate of two molecules are cross-linked to each other, the molecular weight increases. In the formula (5), A is an unsaturated group-containing carboxylic acid residue, and D is an acid dianhydride residue.

The secondary hydroxyl group in the intermediate can be reacted with an acid anhydride to obtain a carboxyl group-containing resin (A1). When the acid anhydride contains acid dianhydride (a3) and acid monoanhydride (a4), a part of the secondary hydroxyl group in the intermediate is reacted with the acid dianhydride (a3), and the secondary hydroxyl group in the intermediate is made. Another part of the reaction with the acid monoanhydride (a4). Thereby, the carboxyl group-containing resin (A1) can be synthesized. At this time, the carboxyl group-containing resin (A1) has a bisphenol fluorene skeleton (S1), a structure (S4), and a structure (S5).

The carboxyl group-containing resin (A1) may further have a structure (S6) represented by the following formula (6). The structure (S6) is produced by reacting only one of the two acid anhydride groups in the acid dianhydride (a3) with the secondary hydroxyl group in the intermediate. In the formula (6), A is an unsaturated group-containing carboxylic acid residue, and D is an acid dianhydride residue.

When the intermediate is synthesized, when a part of the epoxy group in the epoxy compound (a1) is left unreacted, the carboxyl group-containing resin (A1) may have a structure (S2) represented by the formula (2), that is, an epoxy group. . Further, when a part of the structure (S3) in the intermediate remains without reaction, the carboxyl group-containing resin (A1) may have a structure (S3).

When the acid anhydride contains acid dianhydride (a3), the number of structures (S2) and structures (S6) in the carboxyl group-containing resin (A1) is reduced by optimizing the reaction conditions for synthesizing the carboxyl group-containing resin (A1). Or the structure (S2) and the structure (S6) are substantially removed from the carboxyl group-containing resin (A1).

As described above, the carboxyl group-containing resin (A1) may have a bisphenol fluorene skeleton (S1), and may have a structure (S4) when the acid anhydride contains the acid monoanhydride (a4), and when the acid anhydride contains the acid dianhydride (a3) It may have a structure (S5). Further, when the acid anhydride contains the acid monoanhydride (a4), the carboxyl group-containing resin (A1) sometimes has at least one of the structure (S2) and the structure (S3). Further, when the acid anhydride contains the acid dianhydride (a3), the carboxyl group-containing resin (A1) may have at least one of the structure (S2) and the structure (S6). Further, when the acid anhydride contains the acid monoanhydride (a4) and the acid dianhydride (a3), the carboxyl group-containing resin (A1) may have at least one of (S2), structure (S3) and structure (S6).

In addition, when the epoxy compound (a1) itself has a secondary hydroxyl group, that is, for example, when n=1 or more in the following formula (7), the carboxyl group-containing resin (A1) sometimes has an epoxy compound. The structure in which the secondary hydroxyl group in (a1) reacts with an acid anhydride to produce a structure.

Further, the structure of the carboxyl group-containing resin (A1) is rationally derived based on technical common sense, and in reality, 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 in the formula (7) is 1 or more), the carboxyl group-containing resin (A1) is different depending on the amount of the secondary hydroxyl group in the epoxy compound (a1). The structure will vary greatly. Further, when the intermediate is reacted with the acid dianhydride (a3), as described above, there may be a case where two secondary hydroxyl groups present in one molecule of the intermediate are crosslinked by the acid dianhydride (a3). The case where two secondary hydroxyl groups respectively present in the intermediate of two molecules are cross-linked by the acid dianhydride (a3). Therefore, the carboxyl group-containing resin (A1) finally obtained contains a plurality of molecules having different structures from each other, and thus even if 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 carboxylic acid (a2), when the photopolymerization initiator (D) described later is used in combination, it has photoreactivity. Therefore, the carboxyl group-containing resin (A1) can impart photosensitivity (specifically, ultraviolet curability) to the dry film 13. Further, since the carboxyl group-containing resin (A1) has a carboxyl group derived from an acid anhydride, the dry film 13 can be provided with developability based on an alkaline aqueous solution containing an alkali metal salt and an alkali metal hydroxide. At least one. Further, when the acid anhydride contains the acid dianhydride (a3), the molecular weight of the carboxyl group-containing resin (A1) depends on the amount of crosslinking by the acid dianhydride (a3). Therefore, the carboxyl group-containing resin (A1) whose acid value and molecular weight are appropriately adjusted can be obtained. When the acid anhydride contains the acid dianhydride (a3) and the acid monoanhydride (a4), by controlling the amounts of the acid dianhydride (a3) and the acid monoanhydride (a4), and the acid monoanhydride (a4) relative to the acid dianhydride ( The amount of a3) can easily obtain a carboxyl group-containing resin (A1) having a desired molecular weight and acid value.

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

The epoxy compound (a1) has a structure (S7) represented by the following formula (7), for example. n in the formula (7) is, for example, a number in the range of 0 to 20. In order to make the molecular weight of the carboxyl group-containing resin (A1) an appropriate value, the average of n is particularly preferably in the range of 0 to 1. If the average of n is in the range of 0 to 1, especially when the acid anhydride contains acid dianhydride (a3), it is easy to suppress an excessive increase in molecular weight due to the addition of the acid dianhydride (a3).

The unsaturated carboxylic acid (a2) may contain, for example, a compound having only one ethylenically unsaturated group in one molecule. More specifically, the unsaturated group-containing carboxylic acid (a2) may contain, for example, at least one compound selected from the group consisting of acrylic acid, methacrylic acid, and ω-carboxy-polycaprolactone (n≒). 2) monoacrylate, crotonic acid, cinnamic acid, succinic acid mono(2-propenyl methoxyethyl) ester, succinic acid mono(2-methylpropenyl oxyethyl) ester, phthalic acid mono ( 2-propenyl methoxyethyl) ester, mono(2-methylpropenyl oxyethyl) phthalate, mono(2-propenyl methoxypropyl) phthalate, o-phenyl phthalate Mono(2-methylpropenyloxypropyl)carboxylate, mono(2-propenyloxyethyl) maleate, mono(2-methylpropenyloxyethyl) maleate, Β-carboxyethyl acrylate, mono(2-propenyl methoxyethyl) tetrahydrophthalate, mono(2-methylpropenyl oxyethyl) tetrahydrophthalate, hexahydroortho Mono(2-propenyl methoxyethyl) phthalate, and mono(2-methylpropenyl oxyethyl) hexahydrophthalate. The unsaturated carboxylic acid (a2) preferably contains acrylic acid.

When the epoxy compound (a1) and the unsaturated group-containing carboxylic acid (a2) are reacted, a known method can be employed. For example, an unsaturated group-containing carboxylic acid (a2) is added to a solvent solution of the epoxy compound (a1), and a thermal polymerization inhibitor and a catalyst are further added as needed, and stirred and mixed, whereby a reactive solution is obtained. The reactive solution can be more preferably reacted at a temperature of from 60 to 150 ° C by a conventional method, and it is particularly preferred to carry out the reaction at a temperature of from 80 to 120 ° C to obtain an intermediate. The solvent may contain, for example, at least one component selected from the group consisting of ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene and xylene; ethyl acetate and butyl acetate; , cellosolve acetate, butyl cyproterone acetate, carbitol acetate, butyl carbitol acetate, propylene glycol monomethyl ether acetate, etc. Acetate; and, dialkyl glycol ethers. The thermal polymerization inhibitor may contain, for example, at least one of hydroquinone and hydroquinone monomethyl ether. The catalyst may contain, for example, at least one component selected from the group consisting of tertiary amines such as benzyldimethylamine and triethylamine; trimethylbenzylammonium chloride and chlorine. a quaternary ammonium salt such as methyltriethylammonium; triphenylphosphine; and triphenyl stibine.

In particular, it is preferred that the catalyst contains triphenylphosphine. That is, it is preferred to react the epoxy compound (a1) with the unsaturated group-containing carboxylic acid (a2) 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 carboxylic acid (a2) can be particularly promoted, and a reaction of 95% or more, 97% or more, or approximately 100% can be achieved. Rate (conversion rate). Therefore, an intermediate having the structure (S3) can be obtained in a high yield. Further, in the layer containing the cured product of the dry film 13, the occurrence of ion migration can be suppressed, and the insulation reliability of the layer can be further improved.

When the epoxy compound (a1) is reacted with the unsaturated group-containing carboxylic acid (a2), the amount of the unsaturated group-containing carboxylic acid (a2) is 1 mol of the epoxy group of the epoxy compound (a1). Preferably, it is in the range of 0.8 to 1.2 moles. At this time, the dry film 13 having excellent photosensitivity and storage stability can be obtained.

It is also preferred to react the epoxy compound (a1) with the unsaturated group-containing carboxylic acid (a2) in a state in which bubbles are generated. At this time, since the addition polymerization reaction of the unsaturated group can be suppressed, the increase in the molecular weight of the intermediate and the gelation of the solution of the intermediate can be suppressed. Further, excessive coloring of the final product, that is, the carboxyl group-containing resin (A1) can be suppressed.

The intermediate obtained in such a manner has a hydroxyl group which is produced by a reaction of an epoxy group of the epoxy compound (a1) with a carboxyl group of the unsaturated group-containing carboxylic acid (a2).

The acid dianhydride (a3) is a compound having two acid anhydride groups. The acid dianhydride (a3) may contain an acid anhydride of a tetracarboxylic acid. The acid dianhydride (a3) may contain, for example, at least one compound selected from the group consisting of 1,2,4,5-benzenetetracarboxylic dianhydride, diphenyl ketone tetracarboxylic dianhydride, methyl Cyclohexene tetracarboxylic dianhydride, tetracarboxylic dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, ethylene tetracarboxylic dianhydride, 9,9'-bis(3,4-dicarboxyphenyl) Sebacic anhydride, glycerol bis(hydrogen trimellitate) monoacetate, ethylene glycol bis(hydrogen trimellitate), 3,3',4,4'-diphenylphosphonium tetracarboxylic dianhydride 1,3,3a,4,5,9b-hexahydro-5(tetrahydro-2,5-di-oxy-3-furanyl)naphtho[1,2-c]furan-1,3- Diketone, 1,2,3,4-butanetetracarboxylic dianhydride, and 3,3',4,4'-biphenyltetracarboxylic dianhydride. In particular, it is preferred that the acid dianhydride (a3) contains 3,3',4,4'-biphenyltetracarboxylic dianhydride. At this time, it is possible to ensure good developability of the dry film 13 while further suppressing the viscosity of the dry film 13, and it is possible to further improve the insulation reliability and plating resistance of the cured product. The amount of 3,3',4,4'-biphenyltetracarboxylic dianhydride is preferably in the range of 20 to 100 mol%, more preferably 40 to 100, based on the total of the acid dianhydride (a3). Moore% is within the scope, but is not limited to these ranges.

The acid monoanhydride (a4) is a compound having one acid anhydride group. The acid monoanhydride (a4) may contain an acid anhydride of a dicarboxylic acid. The acid monoanhydride (a4) may contain, for example, at least one compound selected from the group consisting of phthalic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, methyl four. Hydrogen phthalic anhydride, methyl nadic acid anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, succinic anhydride, methyl succinic anhydride, maleic anhydride, lemon Tonic anhydride, glutaric anhydride, trimellitic anhydride, cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride, and itaconic anhydride. In particular, it is preferred that the acid monoanhydride (a4) contains 1,2,3,6-tetrahydrophthalic anhydride. That is, it is preferred that the acid anhydride contains 1,2,3,6-tetrahydrophthalic anhydride. That is, it is preferred that the carboxyl group-containing resin (A1) has a structure (S4), and B in the formula (4) contains a 1,2,3,6-tetrahydrophthalic anhydride residue. At this time, it is possible to ensure good developability of the dry film 13 while further suppressing the viscosity of the dry film 13, and it is possible to further improve the insulation reliability and plating resistance of the cured product. The amount of 1,2,3,6-tetrahydrophthalic anhydride is preferably in the range of 20 to 100 mol%, more preferably 40 to 100 mol, based on the total of the acid monoanhydride (a4). Within the range of % of ears, but not limited to these ranges.

When the intermediate is reacted with an acid anhydride, a known method can be employed. For example, an acid anhydride is added to a solvent solution of an intermediate, and a thermal polymerization inhibitor and a catalyst are further added as needed, and stirred and mixed, whereby a reactive solution is obtained. The reactive solution may be reacted at a temperature of 60 to 150 ° C by a conventional method, and it is particularly preferred to carry out the reaction at a temperature of 80 to 120 ° C to obtain a carboxyl group-containing resin (A1). ). As the solvent, catalyst, and polymerization inhibitor, a suitable solvent, catalyst, and polymerization inhibitor can be used, and a solvent, a catalyst, and a polymerization inhibitor used in the synthesis of the intermediate can be used as it is.

In particular, it is preferred that the catalyst contains triphenylphosphine. That is, it is preferred to react the intermediate with an acid anhydride in the presence of triphenylphosphine. In this case, the reaction of the secondary hydroxyl group and the acid anhydride in the intermediate can be particularly promoted, and a reaction rate (conversion ratio) of 90% or more, 95% or more, 97% or more, or approximately 100% can be achieved. Therefore, the carboxyl group-containing resin (A1) having at least one of the structures (S4) and (S5) can be obtained in a high yield. Further, in the layer containing the cured product of the dry film 13, the occurrence of ion migration can be suppressed, and the insulation reliability of the layer can be further improved.

It is also preferred to react the intermediate with an acid anhydride in a state in which bubbles are generated. At this time, an increase in the excess molecular weight of the carboxyl group-containing resin (A1) can be suppressed, whereby the developability of the dry film 13 based on the alkaline aqueous solution can be particularly improved.

When the intermediate is reacted with an acid anhydride, the amount of the acid dianhydride (a3) is preferably in the range of 0.02 to 0.4 mol with respect to 1 mol of the epoxy group of the epoxy compound (a1). Preferably, it is in the range of 0.05 to 0.24 moles. Further, the amount of the acid monoanhydride (a4) is preferably in the range of 0.1 to 0.8 mol, more preferably 0.3 to 0.7 mol, based on 1 mol of the epoxy group of the epoxy compound (a1). In the range. At this time, the carboxyl group-containing resin (A1) whose acid value and molecular weight are appropriately adjusted can be obtained. Moreover, the increase in the excess molecular weight of the carboxyl group-containing resin (A1) can be suppressed, whereby the developability of the dry film 13 based on the alkaline aqueous solution can be particularly improved.

The weight average molecular weight of the carboxyl group-containing resin (A1) is preferably in the range of 700 to 10,000. When the weight average molecular weight is 700 or more, the viscosity of the dry film 13 is further suppressed, and the insulation reliability and plating resistance of the cured product can be further improved. Moreover, when the weight average molecular weight is 10,000 or less, the developability of the dry film 13 based on the alkaline aqueous solution can be particularly improved. The weight average molecular weight of the carboxyl group-containing resin (A1) is more preferably in the range of 900 to 8,000, particularly preferably in the range of 1,000 to 5,000.

Further, the acid value of the solid content of the carboxyl group-containing resin (A1) is preferably in the range of 60 to 140 mgKOH/g. At this time, the developability of the dry film 13 can be particularly improved. It is more preferable if the acid value is in the range of 80 to 135 mgKOH/g, and more preferably in the range of 90 to 130 mgKOH/g.

The carboxyl group-containing resin (A) may contain a carboxyl group-containing resin (hereinafter also referred to as a carboxyl group-containing resin (G)) other than the carboxyl group-containing resin (A1).

The carboxyl group-containing resin (G) is preferably contained in the reaction product of the polyol compound and the polycarboxylic acid, and may contain a component which is not contained in the reactant of the polyol compound and the polycarboxylic acid.

The carboxyl group-containing resin (G) may contain, for example, a compound having a carboxyl group but not having photopolymerization (hereinafter referred to as a component (G1)). The component (G1) contains a polymer such as an ethylenically unsaturated monomer, and the ethylenically unsaturated monomer contains an ethylenically unsaturated compound having a carboxyl group. The ethylenically unsaturated compound having a carboxyl group may contain the following compounds: acrylic acid, methacrylic acid, ω-carboxy-polycaprolactone (n≒2) monoacrylate, and the like. The ethylenically unsaturated compound having a carboxyl group may further contain a reaction product with a dibasic acid anhydride such as pentaerythritol triacrylate or pentaerythritol trimethacrylate. The ethylenically unsaturated monomer may further contain the following ethylenically unsaturated compound having no carboxyl group: 2-(meth)acryloxyethyl phthalate, 2-(methyl) propylene phthalate A (meth) acrylate or the like which is a methoxyethyl 2-hydroxyethyl ester, a linear or branched aliphatic or alicyclic group in which a ring may have a part of an unsaturated bond.

The carboxyl group-containing resin (G) may contain a compound having a carboxyl group and an ethylenically unsaturated group (hereinafter referred to as a component (G2)). a component (G2) containing a resin (hereinafter referred to as a first resin (g)), which is, for example, a reaction product of an intermediate with at least one compound (g3) selected from the group consisting of polycarboxylic acids and anhydrides thereof, This intermediate is a reaction product of an epoxy compound (g1) having two or more epoxy groups in one molecule and an ethylenically unsaturated compound (g2). This intermediate is a polyol compound, and the compound (g3) is a polycarboxylic acid, and thus the first resin (g) is contained in the reactant of the polyol compound and the polycarboxylic acid. The first resin (g), for example, can react an epoxy group in the epoxy compound (g1) with a carboxyl group in the ethylenically unsaturated compound (g2), and then add the compound (g3) to the obtained intermediate. obtain. The epoxy compound (g1) may contain an appropriate epoxy resin: a cresol novolac type epoxy resin, a phenol novolak type epoxy resin, or the like. In particular, the epoxy compound (g1) preferably contains at least one compound selected from the group consisting of a biphenol novolak type epoxy compound and a cresol novolak type epoxy compound. The epoxy compound (g1) may contain only a biphenol novolak type epoxy compound, or may contain only a cresol novolak type epoxy compound. At this time, since the aromatic ring is contained in the main chain of the epoxy compound (g1), the cured product of the photosensitive resin composition is more likely to be less corroded by the oxidizing agent. The epoxy compound (g1) may contain a polymer of the ethylenically unsaturated compound (h). The ethylenically unsaturated compound (h) contains an epoxy group-containing compound (h1) such as glycidyl (meth)acrylate or further contains 2-(methyl)propenyloxyethyl phthalate. The compound (h2) which does not have an epoxy group. The ethylenically unsaturated compound (g2) preferably contains at least one of acrylic acid or methacrylic acid. The compound (g3) contains, for example, at least one compound selected from the group consisting of polycarboxylic acids such as phthalic acid, tetrahydrophthalic acid, and methyltetrahydrophthalic acid; and these An acid anhydride of a polycarboxylic acid.

The component (G2) may further contain a resin (referred to as a second resin (i)) which is a reactant of a polymer of an ethylenically unsaturated monomer and an ethylenically unsaturated compound having an epoxy group, the ethylene The unsaturated monomer contains an ethylenically unsaturated compound having a carboxyl group. 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 carboxyl groups in the polymer. An ethylenically unsaturated compound having a carboxyl group, for example, the following compounds: acrylic acid, methacrylic acid, ω-carboxy-polycaprolactone (n≒2) monoacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, etc. . An ethylenically unsaturated compound having no carboxyl group, and containing, for example, the following compound: 2-(methyl)propenyloxyethyl phthalate, 2-(methyl)propenyloxyethyl phthalate- 2-hydroxyethyl ester, a linear or branched aliphatic or alicyclic (wherein the ring may have a part of an unsaturated bond) (meth) acrylate or the like. The ethylenically unsaturated compound having an epoxy group preferably contains glycidyl (meth)acrylate.

The carboxyl group-containing resin (A) contains, for example, only a carboxyl group-containing resin (A1) or a carboxyl group-containing resin (A1) and a carboxyl group-containing resin (G). The carboxyl group-containing resin (A) preferably contains 30% by mass or more of the carboxyl group-containing resin (A1), more preferably contains 50% by mass or more of the carboxyl group-containing resin (A1), and further preferably contains 100% by mass of the carboxyl group-containing resin. Resin (A1). At this time, the heat resistance and insulation reliability of the cured product of the dry film 13 can be particularly improved. Moreover, the viscosity of the dry film 13 can be sufficiently reduced. Further, the developability of the dry film 13 based on the alkaline aqueous solution can be ensured. Further, the carboxyl group-containing resin (A) may contain only the carboxyl group-containing resin (G).

Specifically, the epoxy resin (B) contained in the dry film 13 will be described.

The epoxy compound (B) can impart thermosetting properties to the dry film 13 . The epoxy compound (B) preferably has at least two epoxy groups in one molecule. The epoxy compound (B) may be a solvent-insoluble epoxy compound or a general-purpose solvent-soluble epoxy compound.

The epoxy compound (B) preferably contains one or more components selected from the group consisting of phenol novolac type epoxy resins (as a specific example, the product model EPICLON N-775 manufactured by DIC Corporation) ), a cresol novolac type epoxy resin (a specific example, a product model EPICLON N-695 manufactured by DIC Corporation), and a bisphenol A novolac type epoxy resin (a specific example, a product manufactured by DIC Corporation) Model EPICLON N-865), bisphenol A type epoxy resin (for example, product type jER1001 manufactured by Mitsubishi Chemical Corporation), bisphenol F type epoxy resin (as a specific example, manufactured by Mitsubishi Chemical Corporation) Product model jER4004P), bisphenol S type epoxy resin (as a specific example, product model EPICLON EXA-1514 manufactured by DIC Corporation), bisphenol AD type epoxy resin, biphenyl type epoxy resin (as a specific example, Mitsubishi Chemical Co., Ltd. product model YX4000), biphenyl aldehyde varnish type epoxy resin (as a specific example, the product model NC-3000 manufactured by Nippon Kayaku Co., Ltd.), hydrogenated bisphenol A ring Oxygen resin (as a specific example, product model ST-4000D manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.), naphthalene type epoxy resin (as a specific example, the product model EPICLON HP-4032, EPICLON HP- manufactured by DIC Corporation) 4700, EPICLON HP-4770), hydroquinone type epoxy resin (as a specific example, YT-1312 manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.), and tertiary catechol type epoxy resin (as Specific examples are a product model EPICLON HP-820 manufactured by DIC Corporation, a dicyclopentadiene type epoxy resin (as a specific example, a product model EPICLON HP-7200 manufactured by DIC Corporation), and an adamantane type epoxy resin. (As a specific example, the product type ADAMANTATE XE-201 manufactured by Idemitsu Kosan Co., Ltd.), bisphenol type epoxy resin (as a specific example, the product model YSLV-80XY manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.), a phenyl ether type epoxy resin (a specific example, a product model YSLV-80DE manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.) and an epoxy resin having a bisphenol fluorene skeleton (as a specific example, having the formula (7) of Epoxy resin), rubbery core-shell polymer modified bisphenol A epoxy resin (as a specific example, the product model MX-156 manufactured by Zhonghua Co., Ltd.), rubbery core-shell polymer modified double A phenol F-type epoxy resin (a specific example, a product model MX-136 manufactured by Chung Ching Co., Ltd.), and a special difunctional epoxy resin (as a specific example, the product model YL7175-500 manufactured by Mitsubishi Chemical Corporation) And YL7175-1000; DIC Co., Ltd. manufactured by EPICLON TSR-960, EPICLON TER-601, EPICLON TSR-250-80BX, EPICLON 1650-75MPX, EPICLON EXA-4850, EPICLON EXA-4816, EPICLON EXA-4822 And EPICLON EXA-9726; the product model YSLV-120TE manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.).

In the present embodiment, the epoxy compound (B) contains a crystalline epoxy resin (B1). The crystalline epoxy resin means an epoxy resin having a melting point. Therefore, especially when the dry film 13 is photosensitive, the developability of the dry film 13 can be improved, and when the dry film 13 contains the carboxyl group-containing resin (A1), the developability is remarkably improved. At this time, the developability of the dry film 13 based on the alkaline aqueous solution can be improved, and the dry film 13 can be developed by using an alkaline aqueous solution containing at least one of an alkali metal salt and an alkali metal hydroxide. The crystalline epoxy resin (B1) may contain, for example, at least one component selected from the group consisting of 1,3,5-gin(2,3-epoxypropyl)-1,3, 5-triazine-2,4,6(1H,3H,5H)-trione, hydroquinone-type crystalline epoxy resin (as a specific example, trade name YDC-1312 manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.) , a biphenyl type crystalline epoxy resin (for example, a trade name YX-4000 manufactured by Mitsubishi Chemical Corporation), and a diphenyl ether type crystalline epoxy resin (as a specific example, Nippon Steel & Sumitomo Chemical Co., Ltd. The product type YSLV-80DE manufactured by the company, the bisphenol type crystalline epoxy resin (as a specific example, the trade name YSLV-80XY manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.), bismuth (hydroxyphenyl) ethane type crystal Epoxy resin (for example, GTR-1800 manufactured by Nippon Kayaku Co., Ltd.) and bisphenol fluorene-type crystalline epoxy resin (as a specific example, epoxy having a structure represented by formula (7) Resin).

The epoxy compound (B) may contain a phosphorus-containing epoxy resin. At this time, the flame retardancy of the cured product of the dry film 13 can be improved. Examples of the phosphorus-containing epoxy resin include a phosphoric acid-modified bisphenol F-type epoxy resin (for example, EPICRON EXA-9726 and EPICRON EXA-9710, manufactured by DIC Corporation), and Nippon Steel & Sumitomo Chemical Co., Ltd. The product model EPOTORT FX-305 manufactured by the company.

The dry film 13 of the present embodiment preferably further contains an unsaturated compound (C) and a photopolymerization initiator (D) containing at least one polymerizable ethylenic unsaturation in one molecule. key. At this time, the dry film 13 can be provided with photosensitivity. Further, excellent alkali developability can be imparted to the non-exposed portion of the dry film.

Specifically, the unsaturated compound (C) and the photopolymerization initiator (D) are exemplified.

The unsaturated compound (C) may contain, for example, at least one compound selected from the group consisting of: a monofunctional (meth) acrylate such as 2-hydroxyethyl (meth)acrylate; and, Alcohol di(meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(methyl) Acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ε-caprolactone modified pentaerythritol hexaacrylate, tricyclodecane dimethanol di(meth) acrylate, etc. Functional (meth) acrylate.

The unsaturated compound (C) preferably contains a trifunctional compound, that is, a compound having three unsaturated bonds in one molecule. At this time, when the dry film 13 is exposed and developed, the resolution can be improved, and the developability of the dry film 13 based on the alkaline aqueous solution can be particularly improved. The trifunctional compound may contain, for example, at least one compound selected from the group consisting of trimethylolpropane tri(meth)acrylate, EO-modified trimethylolpropane tri(meth)acrylate , pentaerythritol tri (meth) acrylate, ethoxylated isocyanuric acid tri(meth) acrylate, ε-caprolactone modified ginseng (2-propenyl methoxyethyl) iso-cyanuric acid Ester, and ethoxylated glycerol tri(meth) acrylate.

The unsaturated compound (C) preferably also contains a phosphorus-containing compound (phosphorus-containing unsaturated compound). At this time, the flame retardancy of the cured product of the dry film 13 can be improved. The phosphorus-containing unsaturated compound may contain, for example, at least one compound selected from the group consisting of 2-methylpropenyloxyethyl phosphate (as a specific example, manufactured by Kyoeisha Chemical Co., Ltd.) Product type LIGHT ESTER P-1M, and LIGHT ESTER P-2M), 2-propenyl methoxyethyl phosphate (as a specific example, the product model LIGHT ACRYLATE P-1A manufactured by Kyoeisha Chemical Co., Ltd.), Diphenyl-2-methylpropenyloxyethyl phosphate (as a specific example, the product model MR-260 manufactured by Daihatsu Industrial Co., Ltd.) and the HFA series manufactured by Showa Polymer Co., Ltd. For example, the addition reaction of dipentaerythritol hexaacrylate with HCA (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) is also available in the product models HFA-6003 and HFA-6007. The addition reaction of caprolactone-modified dipentaerythritol hexaacrylate with HCA (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) is also the commercial model HFA-3003 and HFA. -6127, etc.).

The unsaturated compound (C) may contain a prepolymer. The prepolymer may contain, for example, at least one compound selected from the group consisting of polymerizing a monomer having an ethylenically unsaturated bond and then adding an ethylenically unsaturated group. And, oligomeric (meth) acrylate prepolymers. The oligomeric (meth) acrylate prepolymer may contain, for example, at least one component selected from the group consisting of epoxy (meth) acrylate, polyester (meth) acrylate, Amine ester (meth) acrylate, alkyd resin (meth) acrylate, oxime resin (meth) acrylate, and spirane resin (meth) acrylate.

The photopolymerization initiator (D) contains, for example, a fluorenylphosphine oxide-based photopolymerization initiator (D1). That is, the dry film 13 contains, for example, a fluorenylphosphine oxide-based photopolymerization initiator (D1). In this case, although the photosensitive resin composition contains the carboxyl group-containing resin (A1), it is possible to impart high sensitivity to ultraviolet light to the photosensitive resin composition. Further, the occurrence of ion migration is suppressed in the layer containing the cured product of the photosensitive resin composition, and the insulation reliability of the layer is further improved. Further, the fluorenylphosphine oxide-based photopolymerization initiator (D1) is less likely to interfere with the electrical insulation of the cured product. Therefore, by subjecting the photosensitive resin composition to exposure curing, a cured product excellent in electrical insulating properties can be obtained, and the cured product is suitable as, for example, a solder resist layer, a plating resist layer, an etch resist layer, and an interlayer insulating layer.

The fluorenylphosphine oxide-based photopolymerization initiator (D1) may contain, for example, at least one component selected from the group consisting of 2,4,6-trimethylbenzylidene-diphenyl- Monodecylphosphine oxide photopolymerization initiator such as phosphine oxide, 2,4,6-trimethylbenzimidyl-phenyl-phosphonic acid ethyl ester; and, bis-(2,6-dichlorobenzene) Mercapto) phenylphosphine oxide, bis-(2,6-dichlorobenzhydryl)-2,5-dimethylphenylphosphine oxide, bis-(2,6-dichlorobenzhydryl)- 4-propylphenylphosphine oxide, bis-(2,6-dichlorobenzhydryl)-1-naphthylphosphine oxide, bis-(2,6-dimethoxybenzylidene)phenyl oxide Phosphine, bis-(2,6-dimethoxybenzylidene)-2,4,4-trimethylpentylphosphine oxide, bis-(2,6-dimethoxybenzylidene)- 2,5-Dimethylphenylphosphine oxide, bis-(2,4,6-trimethylbenzylidene)phenylphosphine oxide, (2,5,6-trimethylbenzylidene)- A bis-indenylphosphine oxide-based photopolymerization initiator such as 2,4,4-trimethylpentylphosphine oxide. In particular, it is preferred that the fluorenylphosphine oxide-based photopolymerization initiator (D1) contains 2,4,6-trimethylbenzylidene-diphenyl-phosphine oxide, and is preferably a fluorenylphosphine oxide-based light. The polymerization initiator (D1) contains only 2,4,6-trimethylbenzimidyl-diphenyl-phosphine oxide.

It is preferred that the photopolymerization initiator (D) contains a hydroxyketone-based photopolymerization initiator (D2) in addition to the fluorenylphosphine oxide-based photopolymerization initiator (D1). That is, it is preferred that the dry film 13 contains a hydroxyketone-based photopolymerization initiator (D2). In this case, the dry film 13 can be imparted with further higher photosensitivity than in the case where the hydroxyketone-based photopolymerization initiator (D2) is not contained. Thereby, when the film formed by the dry film 13 is irradiated with ultraviolet rays to be cured, the film can be sufficiently cured from the surface to the deep portion. The hydroxyketone-based photopolymerization initiator (D2) may, for example, be 1-hydroxy-cyclohexyl-phenyl-ketone, methyl phenylglyoxylate or 1-[4-(2-hydroxyethoxy). -phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propenyl)-benzene Methyl]phenyl}-2-methyl-propan-1-one, and 2-hydroxy-2-methyl-1-phenyl-propan-1-one.

The mass ratio of the fluorenylphosphine oxide-based photopolymerization initiator (D1) to the hydroxyketone-based photopolymerization initiator (D2) is preferably in the range of 1:0.01 to 1:10. At this time, the hardenability in the vicinity of the surface of the film formed by the dry film 13 and the hardenability in the deep portion can be uniformly increased.

It is also preferred that the photopolymerization initiator (D) contains bis(diethylamino)diphenyl ketone (D3). That is, it is also preferred that the dry film 13 contains a fluorenylphosphine oxide photopolymerization initiator (D1) and bis(diethylamino)diphenyl ketone (D3), or the dry film 13 contains sulfhydryl oxidation. A phosphine-based photopolymerization initiator (D1), a hydroxyketone-based photopolymerization initiator (D2), and bis(diethylamino)diphenyl ketone (D3). At this time, when the film formed by the dry film 13 is partially exposed and developed, the hardening of the portion which is not exposed is suppressed, whereby the resolution is particularly high. Therefore, a very fine pattern can be formed by the cured product of the dry film 13. In particular, when the interlayer insulating layer of the multilayer printed wiring board is formed from the dry film 13, and a small diameter hole for the through hole is provided in the interlayer insulating layer by photolithography (see FIGS. 2A to F). ), it is possible to form a hole having a small diameter with precision.

The amount of bis(diethylamino)diphenyl ketone (D3) is preferably in the range of 0.5 to 20% by mass based on the fluorenylphosphine oxide-based photopolymerization initiator (D1). When the amount of bis(diethylamino)diphenyl ketone (D3) is 0.5% by mass or more with respect to the fluorenylphosphine oxide-based photopolymerization initiator (D1), the resolution is particularly high. In addition, when the amount of bis(diethylamino)diphenyl ketone (D3) is 20% by mass or less based on the fluorenyl phosphine oxide-based photopolymerization initiator (D1), bis(diethylamino group) Diphenyl ketone (D3) does not easily interfere with the electrical insulation of the cured product of the dry film 13.

The dry film 13 of the present embodiment may further contain a known photopolymerization accelerator, a sensitizer, or the like. The dry film 13 may contain, for example, at least one component selected from the group consisting of benzoin and its alkyl ethers; acetophenones such as acetophenone and benzoin dimethyl ketal; Anthraquinones; 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2, a thioxanthone such as 4-diisopropylthioxanthone; a diphenyl ketone such as diphenyl ketone or 4-benzylidene-4'-methyldiphenyl sulfide; 2,4 -xanthone such as diisopropyldibenzopiperone; and α-hydroxyketones such as 2-hydroxy-2-methyl-1-phenyl-propan-1-one a compound containing a nitrogen atom such as 2-methyl-1-[4-(methylthio)phenyl]-2-(N-morpholinyl)-1-propanone. In addition to the photopolymerization initiator (D), the dry film 13 may further contain p-dimethyl benzoic acid ethyl ester, p-dimethylamino benzoic acid isoamyl ester, benzoic acid 2-dimethylaminoethyl ester, and the like. A known photopolymerization accelerator or sensitizer such as a tertiary amine system. The dry film 13 may contain at least one of a photopolymerization initiator for visible light exposure and a photopolymerization initiator for near-infrared exposure as needed. In addition to the photopolymerization initiator (D), the dry film 13 may further contain a sensitizer for laser exposure, that is, a coumarin derivative such as 7-diethylamino-4-methylcoumarin , carbocyanine pigment system, dibenzopyran (xanthene) pigment system, and the like.

The dry film 13 of the present embodiment preferably further contains a surfactant (E). At this time, when the dry film 13 is formed, generation of bubbles or the like can be suppressed, and a uniform dry film 13 can be easily formed.

The surfactant (E), in particular, preferably has a fluorine atom. At this time, since the surface tension of the resin composition can be largely lowered, the dispersibility of the components of the dry film 13 can be improved, and the dry film 13 having higher uniformity can be easily formed. Examples of the surfactant (E) include, for example, MEGAFACE F-470, MEGAFACE F-477, MEGAFACE F-553, MEGAFACE F-555, MEGAFACE F-556, MEGAFACE F-557, manufactured by DIC Corporation. MEGAFACE F-559, MEGAFACE F-562, MEGAFACE F-565, MEGAFACE F-567, MEGAFACE F-568, MEGAFACE F-571, MEGAFACE R-40, and MEGAFACE R-94; Fluorad FC manufactured by Japan 3M Co., Ltd. -4430 and Fluorad FC-4432; Surfllon S-241, Surflon S-242, Surflon S-243, Surflon S-420, Surflon S-611, Surflon S-651 and Surflon S-386 manufactured by AGC Qingmei Chemical Co., Ltd. And PF636, PF6320, PF656, and PF6520 manufactured by OMNOVA.

The dry film 13 of the present embodiment preferably further contains melamine (F). At this time, it is possible to impart good adhesion to the dry film 13 and to improve the adhesion between the cured product of the dry film 13 and a metal such as copper. Therefore, the dry film 13 is particularly suitable as an insulating material for printed wiring boards. Moreover, the plating resistance of the cured product of the dry film 13 can be improved, that is, the whitening resistance at the time of electroless nickel/gold treatment.

The amount of the carboxyl group-containing resin is preferably in the range of 5 to 85% by mass based on the dry film 13, and more preferably in the range of 10 to 75% by mass, and in the range of 30 to 60% by mass. It is further preferred.

The amount of the epoxy compound (B) is preferably 0.7 to 2.5 in terms of the equivalent amount of the epoxy group contained in the epoxy compound (B) per equivalent of the carboxyl group contained in the carboxyl group-containing resin (A). In the range of 0.7 to 2.3, it is more preferably in the range of 0.7 to 2.3, and further preferably in the range of 0.7 to 2.0. Further, the crystalline epoxy resin (B1) is preferably in the range of 10 to 100% by mass, more preferably in the range of 30 to 100% by mass, even more preferably in the epoxy compound (B). It is further preferably in the range of 35 to 100% by mass. At this time, in the step before the thermal curing of the dry film 13, the thermosetting reaction of the carboxyl group-containing resin can be suppressed, and the developability is improved.

The amount of the unsaturated compound (C) relative to the carboxyl group-containing resin (A) is preferably in the range of 10 to 50% by mass, more preferably in the range of 21 to 40% by mass, and in the range of 23 to 36% by mass. Further within the range of % is further preferred.

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

When the dry film contains the surfactant (E), the amount of the surfactant (E) relative to the carboxyl group-containing resin (A) is preferably in the range of 0.005 to 5% by mass, more preferably 0.01 to 1%. In the range of 0.02% by mass to 0.5% by mass, it is more preferably in the range of 5% by mass.

When the dry film contains melamine (F), the amount of melamine (F) is preferably in the range of 0.1 to 10% by mass, and in the range of 0.5 to 5% by mass based on the carboxyl group-containing resin (A). Further preferred.

The dry film 13 may further contain components other than the above components as long as the effects of the embodiment are not impaired.

For example, the dry film 13 may contain an inorganic filler material. At this time, it is possible to reduce the hardening and shrinkage of the film formed by the dry film 13. The inorganic filler may contain, for example, at least one material selected from the group consisting of barium sulfate, crystalline cerium oxide, nano cerium oxide, carbon nanotube, talc, bentonite, Aluminum hydroxide, magnesium hydroxide, and titanium dioxide. The dry film 13 and its cured product can be whitened by including a white material such as titanium oxide or zinc oxide in the inorganic filler. The ratio of the inorganic filler in the dry film 13 can be appropriately set, and is preferably in the range of 0 to 300% by mass based on the carboxyl group-containing resin (A).

The dry film 13 may contain at least one resin selected from the group consisting of toluene diisocyanate, morpholine diisocyanate, and the like which are blocked with caprolactam, hydrazine, malonate or the like. Sulphate diisocyanate and hexamethylene diisocyanate blocked isocyanate; melamine resin, n-butyl melamine resin, isobutylated melamine resin, butylated urea resin, butylated melamine urea co-condensation resin, benzoquinone An amine-based resin such as a benzoguanamine co-condensation resin; various thermosetting resins other than the above; ultraviolet curable epoxy (meth) acrylate; bisphenol A type, phenol novolak type, cresol novolac An epoxy resin such as a varnish type or an alicyclic type, a resin obtained by adding (meth)acrylic acid; and a polymer compound such as diallyl phthalate resin, phenoxy resin, amine ester resin or fluororesin.

The dry film 13 may contain a hardener for hardening the epoxy compound. The hardener may contain, for example, at least one component selected from the group consisting of imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-benzene Imidazole derivatives such as imidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; dicyandiamide, Benzyl dimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, 4-methyl An amine compound such as benzyl-N,N-dimethylbenzylamine; an anthracene compound such as hexamethylene or fluorene; a phosphorus compound such as triphenylphosphine; an acid anhydride; a phenol; a thiol; Compound; and, bismuth salt. Commercial products of these components are, for example, 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, 2P4MHZ (all trade names of imidazole compounds) manufactured by Shikoku Chemicals Co., Ltd.; manufactured by San-Apro Co., Ltd. U-CAT3503N, U-CAT3502T (trade names of blocked isocyanate compounds of dimethylamine); DBU, DBN, U-CATSA102, U-CAT5002 (all of which are bicyclic guanidine compounds and salts thereof).

The dry film 13 may contain an adhesive imparting agent other than melamine (F). The adhesion imparting agent is, for example, the following S-triazine derivatives: decylamine, methyl decylamine, benzoguanamine, and 2,4-diamino-6-methylpropenyloxyethyl-S- Triazine, 2-vinyl-4,6-diamino-S-triazine, 2-vinyl-4,6-diamino-S-triazine/isocyanuric acid adduct, 2, 4-Diamino-6-methylpropenyloxyethyl-S-triazine/isocyanuric acid addition product and the like.

The dry film 13 may contain at least one component selected from the group consisting of: a hardening accelerator; a colorant; a copolymer of polyfluorene oxide, acrylate, etc.; a leveling agent; a decane coupling agent Equivalent adhesion imparting agent; thixotropic agent; polymerization inhibitor; antihalation agent; flame retardant; antifoaming agent; antioxidant;

The content of the amine compound in the dry film 13 is preferably as small as possible. In this case, electrical insulation of the layer composed of the cured product of the resin composition is not easily impaired. In particular, the amine compound is preferably 6% by mass or less based on the carboxyl group-containing resin (A), and more preferably 4% by mass or less.

An example of a method of producing the dry film laminate 15 of the present embodiment will be described.

First, a resin composition containing a component of the dry film 13 is prepared. The resin composition may contain an organic solvent. The organic solvent is used for liquidification or varnishing of a resin composition, adjustment of viscosity, adjustment of coatability, adjustment of film formability, and the like.

The organic solvent may contain, for example, at least one compound selected from the group consisting of: linear, branched, quaternary or polyhydric alcohols such as ethanol, propanol, isopropanol, hexanol, ethylene glycol; Ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene and xylene; Swasol series (manufactured by Maruzen Petrochemical Co., Ltd.), Solvesso series (manufactured by ExxonMobil Chemical Company), etc. Petroleum aromatic mixed solvent; celecoxib, butyl acesulfame, etc.; carbitol, carbitol, propylene glycol methyl ether and other propylene glycol alkyl ether; a polypropylene glycol alkyl ether such as propylene glycol methyl ether; an acetate such as ethyl acetate, butyl acetate, celecoxib acetate or carbitol acetate; and a dialkyl glycol ether.

When the organic solvent is contained, the amount of the organic solvent is preferably such that the organic solvent can be quickly volatilized and disappeared when the coating film formed of the resin composition is dried, that is, the organic solvent does not remain in the dry film. The way in 13 is to make adjustments. In particular, the amount of the organic solvent is preferably in the range of 0 to 99.5% by mass, and more preferably in the range of 15 to 60% by mass, based on the entire resin composition. Further, the appropriate ratio of the organic solvent varies depending on the coating method and the like. Therefore, it is preferred to appropriately adjust the ratio according to the coating method.

The resin composition can be formulated by blending a raw material of the resin composition as described above, and by using, for example, a three-roll mill, a ball mill, a sand mill ( A known kneading method such as sand mill) is used for the kneading. When the raw material of the resin composition contains a liquid component or a component having a low viscosity, the resin composition can be prepared by first adding a component other than the liquid component and the component having a low viscosity to the raw material. The kneading is carried out, and then a liquid component, a component having a low viscosity, and the like are added to the obtained mixture and mixed.

In consideration of storage stability and the like, the first agent can be prepared by mixing a part of the components of the resin composition, and the second agent can be prepared by mixing the remaining components. That is, the resin composition may be provided with the first agent and the second agent. In this case, for example, the first compound can be prepared by premixing and dispersing the unsaturated compound (C), a part of the organic solvent, and the thermosetting component in the component of the resin composition, and by disposing the resin composition. The remaining ingredients in the ingredients are mixed and dispersed to prepare a second agent. At this time, the required amount of the first agent and the second agent may be mixed in a timely manner to prepare a mixed liquid, and the mixed liquid is thereby obtained to obtain a dry film 13.

The resin composition may be applied to the base film 12, that is, the polyethylene terephthalate film, and then dried to form a dry film 13 on the base film 12. Thereby, a member having the dry film 13 and the base film 12 which supports the dry film 13 is obtained. The coating method of the resin composition may be selected from known methods, for example, a group consisting of a dipping method, a spray method, a spin coating method, a roll coating method, and a curtain coating method (curtain Coating), and screen printing. In order to volatilize the organic solvent contained in the resin composition, the drying temperature of the resin composition is, for example, in the range of 40 to 150 °C.

Then, the cover film 14, that is, the stretched polypropylene film, is pressed onto the dry film 13, whereby the dry film laminate 15 is obtained. The dry film laminate 15 is wound in, for example, a drum shape for storage. According to the above, the dry film laminate 15 can be formed, and even if it is stored, the epoxy resin or the like is less likely to be deposited, and the cover film 14 is easily peeled off from the dry film 13 .

The dry film 13 of the present embodiment is suitable for an electrically insulating material for printed wiring boards. In particular, the dry film 13 is suitable for a material of an electrically insulating layer such as a solder resist layer, a plating resist layer, an etch resist layer, or an interlayer insulating layer.

The dry film 13 of the present embodiment preferably has a property that when the thickness of the film composed of the dry film 13 is 25 μm, the film composed of the dry film 13 can be developed by an aqueous solution of sodium carbonate. . In this case, since a sufficiently thick electrically insulating layer can be formed by photolithography, the dry film 13 can be widely applied to an interlayer insulating layer, a solder resist layer, or the like in the production of a printed wiring board. Of course, it is also possible to form an electrically insulating layer thinner than the thickness of 25 μm from the dry film 13.

Whether or not the film can be developed by an aqueous solution of sodium carbonate can be confirmed by the following method. The wet coating film was formed by coating a resin composition on a suitable substrate, and then the wet coating film was heated at 80 ° C for 40 minutes to form a film having a thickness of 25 μm and composed of the dry film 13 . In a state where the negative mask is directly adhered to the film, exposure is performed by irradiating the film with ultraviolet rays at a condition of 500 mJ/cm ² through a negative mask, and the negative mask has ultraviolet light. The exposure portion and the non-exposure portion that shields the ultraviolet rays. After the exposure, the following treatment was carried out: a 1% sodium carbonate (Na ₂ CO ₃ ) aqueous solution at 30 ° C was sprayed on the film at an injection pressure of 0.2 MPa for 90 seconds, and then pure water was sprayed at a spray pressure of 0.2 MPa for 90 seconds. . After the film was observed after the treatment, the portion corresponding to the non-exposed portion of the film was removed, and when the residue could not be confirmed, it was confirmed that the film having a thickness of 25 μm can be developed by an aqueous solution of sodium carbonate.

Hereinafter, an example of a method of manufacturing a printed wiring board having an interlayer insulating layer formed of a dry film obtained in the present embodiment will be described with reference to FIGS. 2A to 2F. In the method, a through hole is formed on the interlayer insulating layer by photolithography.

First, as shown in Fig. 2A, the core material 1 is prepared. The core material 1 is provided with, for example, at least one insulating layer 2 and at least one conductor line 3. The conductor line 3 provided on one side of the core material 1 is hereinafter referred to as a first conductor line 3.

The cover film 14 in the dry film laminate 15 is peeled off from the dry film 13. In the present embodiment, the cover film 14 can be easily peeled off from the dry film 13. The dry film 13 is laminated on the core material 1.

Then, the dry film 13 and the core material 1 are first pressed, and then the base film 12 is peeled off from the dry film 13 in the manner shown in FIG. 2B, whereby the dry film 13 is transferred from the base film 12 to the core material 1. on. Thereby, as shown in FIG. 2, the film 4 composed of the dry film 13 is provided on the core material 1.

As shown in Fig. 2D, the film 4 is partially photocured by exposing the film 4. For this purpose, for example, the negative mask is attached to the film 4, and the film 4 is irradiated with ultraviolet rays through the negative mask. The negative photomask includes an exposure portion that allows ultraviolet rays to pass through, and a non-exposure portion that blocks ultraviolet rays, and the non-exposed portion is provided at a position that coincides with the position of the through hole 10. The negative mask is, for example, a photo tool such as a mask film or a dry plate. The ultraviolet light source may be selected from the group consisting of a chemical lamp, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultra high pressure mercury lamp, a xenon lamp, and a metal halide lamp.

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

Further, in the dry film method, the dry film 13 may be laminated on the core material 1, and then the film 4 composed of the dry film 13 may be irradiated with ultraviolet rays through the base film 12 without peeling off the base film 12. Thereby, the film 4 is exposed, and then the base film 12 is peeled off from the film 4 before the development process.

Then, by performing development processing on the film 4, the unexposed portion 5 of the film 4 shown in Fig. 2D is removed, whereby the through hole 10 is formed in the manner shown in Fig. 2E. Set the hole 6 on it. In the development treatment, an appropriate developer corresponding to the composition of the dry film 13 can be used. The developer is, for example, an alkaline aqueous solution or an organic amine, and the alkaline aqueous solution contains at least one of an alkali metal salt and an alkali metal hydroxide. The alkaline aqueous solution, more specifically, contains, for example, at least one component selected from the group consisting of sodium carbonate, potassium carbonate, ammonium carbonate, sodium hydrogencarbonate, potassium hydrogencarbonate, ammonium hydrogencarbonate, sodium hydroxide , potassium hydroxide, ammonium hydroxide, tetramethylammonium hydroxide, and lithium hydroxide. The solvent in the alkaline aqueous solution may be only water or a mixture of water and a hydrophilic organic solvent such as a lower alcohol. 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 aqueous alkaline solution containing at least one of an alkali metal salt and an alkali metal hydroxide, and particularly preferably an aqueous sodium carbonate solution. At this time, it is possible to achieve an increase in the working environment and a reduction in the burden of waste disposal.

Then, the film 4 is hardened by heating it. The heating conditions, for example, the heating temperature is in the range of 120 to 200 ° C, and the heating time is in the range of 30 to 120 minutes. When the film 4 is thermally cured in this manner, the properties such as strength, hardness, and chemical resistance of the interlayer insulating layer 7 can be improved.

The film 4 may be further irradiated with ultraviolet rays before or after heating, or before and after heating, as needed. At this time, the photocuring of the film 4 can be further performed.

According to the above, the interlayer insulating layer 7 can be provided on the core material 1, and the interlayer insulating layer 7 is composed of a cured product of the dry film 13. The second conductor line 8 and the perforated plating 9 may be provided on the interlayer insulating layer 7 by a known method such as an additive method. Thereby, as shown in FIG. 2F, a printed wiring board 11 having the first conductor line 3, the second conductor line 8, and the interlayer insulating layer 7 interposed between the first conductor line 3 and the second conductor can be obtained. Between the lines 8; and the through hole 10, the first conductor line 3 and the second conductor line 8 are electrically connected. Further, in FIG. 2F, the perforated plating 9 has a tubular shape in which the inner surface of the hole 6 is covered, but the perforated plating 9 may be entirely filled inside the hole 6.

Further, before the perforated plating 9 as in FIG. 2F is provided, the entire inner surface of the hole 6 and a part of the outer surface of the interlayer insulating layer 7 can be roughened. In such a manner, a part of the outer surface of the interlayer insulating layer 7 and the inner surface of the hole 6 are roughened, whereby the adhesion of the core material 1 to the perforated plating 9 can be improved.

An example of a method of manufacturing a printed wiring board having a solder resist layer formed of the dry film 13 obtained in the present embodiment will be described.

First, prepare the core material. The core material is provided with, for example, at least one insulating layer and at least one conductor line. A film is formed by the dry film 13 on the surface of the core material on which the conductor line is provided. As a method of forming the film, the same method as in the case of forming the interlayer insulating layer described above can be employed. The portion is hardened by exposing the film. The exposure method may be the same as the above-described method of forming the interlayer insulating layer. Then, the unexposed portion of the film is removed by subjecting the film to development treatment, whereby the exposed portion of the film remains on the core material. Then, the film on the core material is hardened by heating it. The developing method and the heating method may be the same as those in the case of forming the interlayer insulating layer described above. The film may be further irradiated with ultraviolet rays before or after heating, or before and after heating, as needed. At this time, the photocuring of the film can be further performed.

According to the above, the solder resist layer can be provided on the core material, and the solder resist layer is composed of the cured product of the dry film 13. Thereby, it is possible to obtain a printed wiring board comprising: a core material having an insulating layer and a conductor line thereon; and a solder resist layer partially covering the surface of the core material on which the conductor line is provided. [Examples]

Hereinafter, the present invention will be specifically described by way of examples.

(1) Synthesis of a carboxyl group-containing resin In a four-necked flask equipped with a reflux condenser, a thermometer, an air blowing tube, and a stirrer, the raw material components shown in the column of "First Reaction" in Table 1 were added, and air was carried out. These raw material components are stirred in a bubble state, thereby blending the mixture. The mixture was stirred while being air-bubble in a four-necked flask, and heated at the reaction temperature and reaction time shown in the "Reaction conditions" column of the "First reaction" column. Thereby, a solution of the intermediate is formulated. Then, the raw material components shown in the "second reaction" column of Table 1 were placed in a solution of the intermediate in the four-necked flask, and the solution in the four-necked flask was stirred while air bubbling. The heating was carried out by the reaction temperature and the reaction time shown in the column of "Reaction conditions (1)" in the "second reaction" column. Then, in addition to the synthesis example A-6, the solution in the four-necked flask was stirred while air bubbling was performed, as shown in the column of "reaction conditions (2)" in the "second reaction" column. The reaction temperature and the reaction time are used for heating. Thereby, a 65 mass% solution of the carboxyl group-containing resin was obtained. The weight average molecular weight and acid value of the carboxyl group-containing resin are shown in Table 1. The molar ratio between the components is also shown in Table 1.

In addition, the details of the components shown in the column (a1) in Table 1 are as follows. ‧Epoxy compound 1: A bisphenol fluorene type epoxy compound having an epoxy equivalent of 250 g/eq, which is represented by the formula (7), and all of R ₁ to R ₈ in the formula (7) are hydrogen. ‧Epoxy compound 2: a bisphenol fluorene type epoxy compound having an epoxy equivalent of 279 g/eq, which is represented by the formula (7), and both of R ₁ and R ₅ in the formula (7) are a methyl group, and R ₂ ～ R ₄ and R ₆ to R ₈ are all hydrogen.

[Table 1]

(2) Preparation of resin composition A part of the components shown in the "composition" column of Tables 2 to 3 to be described later were blended by a three-roll mill. Then, the composition was transferred to a flask, and all the components shown in Tables 2 to 3 described below were stirred and mixed, whereby the resin compositions of the examples and the comparative examples were obtained. The details of the components shown in Tables 2 to 3 are as follows. ‧ Crystalline epoxy resin (YX4000): Biphenyl type crystalline epoxy resin, manufactured by Mitsubishi Chemical Corporation, trade name YX-4000, melting point 105 ° C, epoxy equivalent 187 g / eq. ‧ Crystalline Epoxy Resin (YDC1312): Hydroquinone-type crystalline epoxy resin, manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., trade name YDC-1312, melting point 138-145 ° C, epoxy equivalent 176 g/eq. ‧Amorphous epoxy resin solution (EXA4816): A bisphenol A type epoxy resin containing a long-chain carbon chain (manufactured by DIC Corporation, product model EPICLON EXA-4816, in a solid content of 90%) A liquid resin (epoxy equivalent: 410 g/eq) was dissolved in diethylene glycol monoethyl ether acetate (the epoxy equivalent in terms of 90% solid content was 455.56 g/eq). ‧ Amorphous epoxy resin solution (N-695): a cresol novolac type epoxy resin (manufactured by DIC Corporation, product type EPICLON N-695, softening point 90) in a solid content of 75% A solution obtained by dissolving ethylene glycol monoethyl ether acetate at ～100° C., an epoxy equivalent of 214 g/eq (the epoxy equivalent in terms of solid content of 75% was 285.33 g/eq). ‧ Unsaturated compound (TMPTA): Trimethylolpropane triacrylate. ‧ Unsaturated compound (DPHA): Dipentaerythritol hexaacrylate, manufactured by Nippon Kayaku Co., Ltd., product model KAYARAD DPHA. ‧Photopolymerization initiator (TPO): 2,4,6-trimethylbenzimidyl-diphenyl-phosphine oxide, manufactured by BASF Corporation, trade name Irgacure TPO. ‧ Photopolymerization initiator (IC184): 1-hydroxy-cyclohexyl-phenyl-ketone, manufactured by BASF Corporation, trade name Irgacure 184. ‧ Photopolymerization initiator (EAB): 4,4'-bis(diethylamino)diphenyl ketone. ‧ Surfactant (F-477): Manufactured by DIC Corporation, product model MEGAFACE F-477. ‧ Surfactant (F-556): Manufactured by DIC Corporation, product model MEGAFACE F-556. ‧ Melamine: Made of Nissan Chemical Industry Co., Ltd., melamine fine powder, dispersed in a photosensitive resin composition in an average particle diameter of 8 μm. ‧Antioxidant: A hindered phenolic antioxidant, manufactured by BASF, under the trade designation IRGANOX 1010. ‧ Blue pigment: phthalocyanine blue. ‧ Yellow pigment: 1,1'-[(6-phenyl-1,3,5-triazine-2,4-diyl)diimido]bis(9,10-nonanedione). ‧ Barium sulfate: manufactured by 堺Chemical Industries Co., Ltd., product model BARIACE B31. ‧ Talc: Made by Japan Talc, product model SG-2000. ‧ Bentonite: manufactured by Rheox, the product model BENTONE SD-2. ‧ Rheology regulator: manufactured by BYK Japan Co., Ltd., product model BYK-430. ‧ Solvent: methyl ethyl ketone.

[Examples 1 to 13 and Comparative Examples 1 to 4] [Production of dry film and dry film laminate] The resin composition was first applied to a base film by an applicator, that is, polyethylene terephthalate. The ester film was further dried by heating at 80 ° C for 30 minutes and then at 110 ° C for 5 minutes to form a dry film having a thickness of 25 μm. Then, a biaxially stretched polypropylene film as a cover film was overlaid on the dry film, and the cover film was pressed by a roller at 40 ° C, whereby a dry film laminate was obtained.

[Production test piece] A glass epoxy copper-clad laminate (FR-4 type) having a copper foil having a thickness of 35 μm was prepared. On this glass epoxy-clad laminate, a comb-shaped electrode as a conductor line was formed by a subtractive method, thereby obtaining a printed wiring board having a line width/space width of 100 μm/100 μm. A conductor portion CZ-8100 manufactured by MEC Co., Ltd. was used to dissolve and remove the surface portion of the conductor wiring of the printed wiring board having a thickness of about 1 μm, thereby roughening the conductor wiring. Then, the cover film of the dry film laminate is peeled off, and then the dry film is heated and laminated on the printed wiring board. The heating lamination was carried out under the conditions of 0.5 MPa, 80 ° C, and 1 minute using a vacuum laminator. Thereby, a film having a thickness of 25 μm was formed on the printed wiring board. In a state in which the base film is superposed on the film, and in a state in which the negative mask including the circular non-exposed portion having a diameter of 80 μm is in direct contact with the base film, the self-base film is polyethylene terephthalate. On the diester film, the film was irradiated with ultraviolet rays at a condition of 400 mJ/cm ² through a negative mask. Then, the base film was peeled off from the film, and a 1% sodium carbonate aqueous solution of 30 ° C was sprayed on the film at an ejection pressure of 0.2 MPa for 90 seconds. Then, washing was performed by spraying pure water on the film for 90 seconds at an ejection pressure of 0.2 MPa. Thereby, the unexposed portion of the film is removed and a hole is formed. Then, the film was heated at 160 ° C for 60 minutes, and then the film was further irradiated with ultraviolet rays at a condition of 1000 mJ/cm ² . Thereby, a layer composed of a cured product of a dry film is formed on the printed wiring board. Thereby a test piece is obtained.

[Evaluation Test] For each of the examples and comparative examples, an evaluation test was carried out. However, in Comparative Example 2, when the cover film was peeled off, since the dry film was adhered to the cover film, the evaluation of (2) to (6) was not performed. Further, in Comparative Examples 3 and 4, since the development residue was generated in the development processing step, the evaluation of (2) to (6) was not performed.

(1) Developability For each of the examples and the comparative examples, a film having a thickness of 25 μm composed of a dry film was formed on the printed wiring board by the same method as in the case of producing a test piece. The film was subjected to development treatment without exposure. At the time of development processing, a 1% sodium carbonate aqueous solution of 30 ° C was sprayed on the film at an injection pressure of 0.2 MPa for 90 seconds, and then pure water was sprayed at an injection pressure of 0.2 MPa for 90 seconds. The treated printed wiring board was observed and the results were evaluated in the following manner. A: All the film is removed. B: A part of the film remains on the printed wiring board.

(2) Resolution The pores formed on the layer composed of the cured product in the test pieces of the respective Examples and Comparative Examples were observed, and the results were evaluated in the following manner. A: The diameter of the bottom of the hole is 70 μm or more. B: The diameter of the bottom of the hole is less than 70 μm. C: Unable to form a clear hole.

(3) Plating resistance First, a commercially available electroless nickel bath was used to form a nickel plating layer on a layer composed of a cured product in the test pieces of the respective Examples and Comparative Examples, and a commercially available electroless plating was used. Gold bath to form a gold plating layer. Thereby, a metal layer composed of a nickel plating layer and a gold plating layer is formed on the layer composed of the cured product. The layer composed of the cured material and the metal layer were visually observed. Further, a cellophane adhesive tape peeling test was performed on the layer composed of the cured product and the metal layer. The results were evaluated in the following manner. A: The appearance of the layer composed of the cured product and the metal layer was not confirmed to be abnormal, and the layer composed of the cured product was not peeled off due to the cellophane adhesive tape peeling test. B: Discoloration was confirmed in the layer composed of the cured product, but the layer formed of the cured product was not peeled off due to the cellophane adhesive tape peeling test. C: It was confirmed that the layer composed of the cured product floated, and the layer composed of the cured product was peeled off due to the cellophane adhesive tape peeling test.

(4) Insulation between wires A bias voltage of 30 V of direct current (DC) was applied to the conductor lines (comb electrodes) in the test pieces of the respective examples and comparative examples, and the printed wiring board was exposed to 121. °C, 97% relative humidity (RH) test environment for 120 hours. The resistance value between the comb-shaped electrodes of the layer composed of the hardened material was continuously measured in this test environment, and the results were evaluated in accordance with the following evaluation criteria. A: The resistance value was maintained at 10 ⁶ Ω or more from the start of the test to 120 hours. B: The resistance value was maintained at 10 ⁶ Ω or more from the start of the test to the lapse of 100 hours, but the resistance value was less than 10 ⁶ Ω from the start of the test until 120 hours passed. C: The resistance value was less than 10 ⁶ Ω from the start of the test until 100 hours passed.

(5) Interlayer insulation The conductive tape was adhered to the layer composed of the cured material in the test pieces of the respective Examples and Comparative Examples. While applying a bias voltage of DC 100 V to the conductive tape, the printed wiring board was exposed to a test environment of 130 ° C and 85% RH for 60 hours. The resistance value between the conductor wiring of the layer composed of the cured product and the conductive tape was continuously measured in this test environment, and the results were evaluated in accordance with the following evaluation criteria. A: The resistance value was maintained at 10 ⁶ Ω or more from the start of the test until 50 hours passed. B: The resistance value was maintained above 10 ⁶ Ω from the start of the test to 35 hours, but the resistance value was less than 10 ⁶ Ω from the start of the test until 50 hours passed. C: The resistance value was less than 10 ⁶ Ω from the start of the test until 35 hours passed.

(6) Pressure cooker test (PCT) The test pieces of the respective examples and comparative examples were placed in an environment of 121 ° C and 100% RH for 80 hours, and then the cured product was evaluated according to the following evaluation criteria. The appearance of the layer. A: No abnormality was observed in the layer composed of the cured product. B: Discoloration was observed in the layer composed of the cured product. C: A large discoloration was observed in the layer composed of the cured product, and a part of the expansion occurred.

(7) Surface state of the coating film The resin composition of each of the examples and the comparative examples was applied onto a film made of polyethylene terephthalate by an applicator, and then dried by heating at 95 ° C for 25 minutes. Then, the film was observed and evaluated according to the following evaluation criteria. A: It is a uniform surface state. B: There are some places where the film thickness is uneven. C: There is a pinhole.

(8) Dry film stability 1 In each of the examples and comparative examples, immediately after the production of the dry film laminate, immediately after storage at 20 ° C for 2 weeks, at this time, the dry film laminate was evaluated according to the following evaluation criteria. Whether there is any foreign matter that produces needle-like crystals. A: No foreign matter like needle crystals was observed. B: Foreign matter similar to needle crystals was observed on the inner surface of the cover film (the surface in contact with the dry film). C: Foreign matter similar to needle crystals was observed on the outside of the cover film (opposite to the face in contact with the dry film).

This result is shown in the column of "Dry Film Stability 1 (OPP)" in Tables 2 and 3. Moreover, for the comparative evaluation, the evaluation test was performed similarly in the case where the cover film was changed to a polyethylene terephthalate (PET) film, and the case where it changed to a polyethylene (PE) film. The results are shown in the fields of "dry film stability 1 (PET)" and "dry film stability 1 (PE)" in Tables 2 and 3, respectively.

(9) Dry film stability 2 In each of the examples and the comparative examples, after the laminate of the dry film was produced, it was wound into a roll shape and stored at 20 ° C for 2 weeks, at which time, according to the following evaluation criteria To evaluate the presence or absence of foreign matter in the dry film laminate that produces needle-like crystals. A: No foreign matter like needle crystals was observed. B: Foreign matter similar to needle crystals was observed on the inner surface of the base film (the surface in contact with the dry film) or on the inner surface of the cover film. C: Foreign matter similar to needle crystals was observed on the outside of the base film (opposite to the face in contact with the dry film) or on the outside of the cover film.

This result is shown in the column of "Dry Film Stability 2 (OPP)" in Tables 2 and 3. Moreover, for the comparative evaluation, the evaluation test was performed similarly in the case where the cover film was changed to a polyethylene terephthalate (PET) film, and the case where it changed to a polyethylene (PE) film. The results are shown in the fields of "dry film stability 2 (PET)" and "dry film stability 2 (PE)" in Tables 2 and 3, respectively.

(10) Cover film peelability In each of the examples and comparative examples, the peeling property of the cover film was evaluated in accordance with the following evaluation criteria. A: The cover film was easily peeled off, and no dry film sticking was observed on the cover film. B: The cover film was easily peeled off, but dry film sticking was observed on the cover film. C: The cover film was difficult to peel off, and a dry film adhesion was observed on the cover film.

The results are shown in the "cover film peelability (OPP)" column in Tables 2 and 3. Moreover, for the comparative evaluation, the evaluation test was performed similarly in the case where the cover film was changed to a polyethylene terephthalate (PET) film, and the case where it changed to a polyethylene (PE) film. The results are shown in the fields of "covering film peeling property (PET)" and "covering film peeling property (PE)" in Tables 2 and 3, respectively.

The evaluation results of the above evaluation test are shown in Tables 2 and 3. In addition, the "crystalline epoxy E/A" in Tables 2 and 3 is equivalent to the epoxy group contained in the crystalline epoxy resin (B1) with respect to the carboxyl group-containing resin (A); "Amorphous ring The oxygen E/A" is an equivalent of the epoxy group contained in the crystalline epoxy resin (B1) with respect to 1 equivalent of the carboxyl group contained in the carboxyl group-containing resin (A); "epoxy whole E/A" is relative to the The carboxyl group resin (A), the equivalent of the epoxy group contained in the epoxy compound.

[Table 2]

[table 3]

According to the above results, if the cover film is a polyethylene film and the resin composition contains a crystalline epoxy resin, foreign matter similar to needle crystals is observed on the outer surface of the cover film. This foreign matter resembling needle crystals was analyzed as a crystalline epoxy resin. From this phenomenon, it is presumed that the crystalline epoxy resin dissolved in the dry film penetrates the polyethylene film and cannot be kept in a dissolved state, thereby crystallizing. Further, when it was stored in a state of being wound into a roll, foreign matter similar to needle crystals was observed on the outer surface of the base film which was in contact with the cover film. This is considered to be because the crystalline epoxy resin dissolved in the dry film adheres and crystallizes on the outer surface of the base film after penetrating the cover film, that is, the polyethylene film, and the base film is made of a polyethylene film. A stronger polyethylene terephthalate film.

If the cover film is a polyethylene terephthalate film, a dry film adheres to the cover film. This is considered to be because the dry film before curing has a strong adhesion to the polyethylene terephthalate film, and the same material as the base film is used.

On the other hand, when the dry film contains a crystalline epoxy resin and the base film of the dry film laminate is a polyethylene terephthalate film, if the cover film is an extended polypropylene film, the crystalline epoxy can be prevented. The resin penetrates or precipitates, and good stability can be obtained. Moreover, when the base film is peeled off, it can be easily peeled off without the dry film sticking.

The dry film of the first aspect includes a base film 12, a dry film 13 and a cover film 14, and the layers are sequentially laminated, wherein the base film 12 is a polyethylene terephthalate film, and the dry film 13 contains a carboxyl group. The resin (A) and the crystalline epoxy resin (B1), and the cover film 14 is an extended polypropylene film.

According to the first aspect, it is possible to suppress the precipitation of the crystalline epoxy resin on the outer surface of the dry film laminate, and it is possible to suppress the change in the composition of the dry film. Thereby, the storage stability of the dry film laminate can be improved. Further, by suppressing the precipitation of the crystalline epoxy resin, it is possible to suppress the occurrence of the powder composed of the crystalline epoxy resin on the outer surface of the dry film laminate. Further, it is possible to ensure good peelability of the cover film and the dry film.

According to the first aspect, it is possible to impart thermosetting properties to the dry film.

The dry film of the second aspect may further contain, in the first aspect, an unsaturated compound (C) and a photopolymerization initiator (D) having at least one polymerizable group in one molecule. Ethylene unsaturated bond.

According to the second aspect, the dry film can be provided with photosensitivity. Further, excellent alkali developability can be imparted to the non-exposed portion of the dry film.

The dry film of the third aspect may further comprise a surfactant (E) for the first or second aspect.

According to the third aspect, when a dry film is formed, generation of bubbles or the like can be suppressed, and a uniform dry film can be easily formed.

In the dry film of the fourth aspect, for any of the first to third aspects, the carboxyl group-containing resin (A) may contain a reactant of a polyol compound and a polyvalent carboxylic acid, and a polymerization average molecular weight of the reactant. It may be in the range of 700 to 40,000, and the acid value of the aforementioned reactant may be in the range of 50 to 200 mgKOH/g.

According to the fourth aspect, the viscosity of the dry film can be further suppressed, and the insulation reliability and the plating resistance of the cured product can be further improved. Moreover, the developability of the dry film based on the alkaline aqueous solution can be particularly improved.

The dry film of the fifth aspect, for any of the first to fourth aspects, the carboxyl group-containing resin (A) may comprise a reactant of an intermediate and an acid anhydride, that is, a carboxyl group-containing resin (A1), the intermediate It is a reaction product of an epoxy compound (a1) having a bisphenol fluorene skeleton and an unsaturated carboxylic acid (a2).

According to the fifth aspect, it is possible to impart high heat resistance and plating resistance to the cured product of the dry film.

The dry film of the sixth aspect may further comprise melamine (F) for any of the first to fifth aspects.

According to the sixth aspect, it is possible to impart good adhesion to the dry film and to improve the adhesion between the cured product of the dry film and a metal such as copper. Therefore, it is particularly suitable as an insulating material for printed wiring boards. Moreover, the plating property of the cured product of the dry film, that is, the whitening resistance at the time of electroless nickel/gold treatment can be improved.

1‧‧‧ core material
2‧‧‧Insulation
3‧‧‧Conductor line (first conductor line)
4‧‧ ‧ film
5‧‧‧Unexposed parts
6‧‧‧ hole
7‧‧‧Interlayer insulation
8‧‧‧Second conductor line
9‧‧‧Perforated plating
10‧‧‧through holes
11‧‧‧Printed circuit board
12‧‧‧Base film
13‧‧‧Dry film
14‧‧‧ Cover film
15‧‧‧ dry film laminar body

Fig. 1 is a cross-sectional view showing a dry film laminate according to an embodiment of the present invention. 2A to 2F are cross-sectional views showing a step of manufacturing a multilayer printed wiring board from the same dry film laminate as described above.

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12‧‧‧Base film

13‧‧‧Dry film

14‧‧‧ Cover film

15‧‧‧ dry film laminar body

Claims (6)

A dry film laminate comprising a base film, a dry film and a cover film, wherein the base film is a polyethylene terephthalate film, and the dry film contains a carboxyl group-containing resin (A) And the crystalline epoxy resin (B1), and the cover film is an extended polypropylene film. The dry film laminate according to claim 1, wherein the dry film further comprises an unsaturated compound (C) and a photopolymerization initiator (D), the unsaturated compound (C) having at least one in one molecule Polymerized ethylenically unsaturated bonds. The dry film laminate according to claim 1 or 2, wherein the dry film further comprises a surfactant (E). The dry film laminate according to claim 1 or 2, wherein the carboxyl group-containing resin (A) contains a reactant of a polyol compound and a polyvalent carboxylic acid, and the weight average molecular weight of the reactant is in the range of 700 to 40,000. Further, the acid value of the above reactant is in the range of 50 to 200 mgKOH/g. The dry film laminate according to claim 1 or 2, wherein the carboxyl group-containing resin (A) contains a carboxyl group-containing resin (A1), and the carboxyl group-containing resin (A1) is a reactant of an intermediate and an acid anhydride. It is a reaction product of the epoxy compound (a1) and the unsaturated group-containing carboxylic acid (a2), the epoxy compound (a1) has a bisphenol fluorene skeleton, and the bisphenol fluorene skeleton 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. . The dry film laminate according to claim 1 or 2, wherein the dry film further comprises melamine (F).