WO2010052811A1

WO2010052811A1 - Photocurable resin composition, dry film and cured product of the photocurable resin composition, and printed wiring board using the photocurable resin composition, the dry film, and the cured product

Info

Publication number: WO2010052811A1
Application number: PCT/JP2009/003037
Authority: WO
Inventors: 秋山学; 峰岸昌司; 有馬聖夫
Original assignee: 太陽インキ製造株式会社
Priority date: 2008-11-07
Filing date: 2009-06-30
Publication date: 2010-05-14
Also published as: KR20110086814A; KR101693900B1; CN102272677B; TWI420243B; JP2010113241A; TW201032003A; CN102272677A

Abstract

Disclosed is a photocurable resin composition that can form a dried coating film, which is highly dry to the touch, has high sensitivity, and can form a cured film which is soft and particularly has a high insulating resistance under high temperature and humidified conditions. Also disclosed are a dry film and a cured product of the photocurable resin composition, and a printed wiring board comprising a cured film such as a solder resist formed using the photocurable resin composition, the dry film and the cured product. The photocurable resin composition is alkaline-developable and comprises a photosensitive resin having a structure represented by general formula (I), a carboxyl group-containing resin, and a photopolymerization initiator. Preferably, the photocurale resin composition further comprises a heat curable component and more preferably further comprises a colorant. In general formula (I), R¹s, which may be the same or different, represent a hydrogen atom and an organic group having 1 to 20 carbon atoms; R² represents at least one functional group selected from the group consisting of alkyl groups having 1 to 10 carbon atoms, alkylene groups having 1 to 10 carbon atoms, and phenylene groups; R³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R⁴ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R⁵ represents a hydrogen atom or a methyl group; p is an integer of 1 to 5; q is an integer of 3 or more; m is an integer of 1 to 4; and n is an integer of 1 to 10.

Description

Photocurable resin composition, dry film and cured product thereof, and printed wiring board using them

The present invention relates to a photocurable resin composition that can be developed with a dilute alkaline aqueous solution, particularly a composition for a solder resist that is photocured by ultraviolet exposure or laser exposure, a dry film and a cured product thereof, and a cure formed using them The present invention relates to a printed wiring board having a film.

Conventionally, alkali development type photosensitive resin compositions have been used in large quantities as solder resists for printed wiring boards. The solder resist is intended to protect the circuit of the printed circuit board, and is mainly composed of a carboxyl group-containing resin, a polyfunctional acrylate compound, a photopolymerization initiator, a thermosetting resin, and the like. As the polyfunctional acrylate compounds, liquid polyfunctional polyester acrylates are widely used mainly from the viewpoints of high sensitivity and development resistance. However, in the case of a contact exposure method in which a negative film is directly attached to a dry coating film at the time of exposure, the dry coating film needs to be dry to the touch (tack-free property). In the case of a photosensitive resin composition using a large amount of liquid polyfunctional polyester acrylate in order to improve photocurability, there is a problem that the dryness of the dry coating film is poor. Therefore, the amount of liquid polyfunctional polyester acrylate used is limited. On the other hand, an attempt to improve touch dryness using semi-solid polyester (meth) acrylates has been proposed (see Patent Document 1). However, in this case, since the polyester (meth) acrylate is bifunctional and semi-solid, the sensitivity is lowered, and the softening point of the dried coating film is improved, so that the developability is lowered. It was.

On the other hand, as described above, the solder resist is used for the purpose of protecting the surface layer circuit of the printed wiring board, and requires high solder heat resistance and electrical insulation. However, since the photosensitive resin is an acrylate-based compound, there is still a point to be improved in terms of electrical insulation, which is inferior in hydrophobicity and alkali resistance, and has a low insulation resistance value under high temperature humidification conditions. It has been regarded as a problem that it easily causes migration and causes a short circuit between circuits.

On the other hand, Patent Document 2 contains a carboxyl group obtained by reacting a polybasic acid anhydride with a reaction product of an epoxy compound having two or more epoxy groups in one molecule and an unsaturated group-containing monocarboxylic acid. Carboxylic group-containing product obtained by reacting a reaction product obtained by reacting an unsaturated group-containing monocarboxylic acid with a reaction product of a photosensitive resin, a novolak-type phenolic resin, and an alkylene oxide. An example of a photosensitive composition having good dryness to the touch and excellent adhesion by using a photosensitive resin in combination is disclosed. However, a carboxyl group-containing photosensitive resin obtained by reacting a reaction product of a novolak-type phenol resin with an alkylene oxide with an unsaturated group-containing monocarboxylic acid and reacting the resulting reaction product with a polybasic acid anhydride. Adds an unsaturated group-containing carboxylic acid and a polybasic acid anhydride to the hydroxyl group produced by ring opening of the alkylene oxide, so the content of unsaturated groups decreases when trying to obtain the required acid value, There was a trade-off relationship between sensitivity and development that a necessary acid value could not be obtained if an attempt was made to contain many unsaturated groups. *

International Publication WO03 / 075095A1 (Claims) JP 2003-280189 A (Claims)

The present invention has been made in view of the prior art as described above, and is excellent in dryness to touch of a dry coating film, highly sensitive and flexible, solder heat resistance, electroless gold plating resistance, moisture resistance, electrical insulation. It is an object of the present invention to provide a photo-curable resin composition that can form a cured film such as a solder resist having excellent insulation resistance and particularly high insulation resistance when humidified at high temperature.
Furthermore, the object of the present invention is to obtain a dry film and a cured product excellent in various properties as described above obtained by using such a photocurable resin composition, and to cure a solder resist or the like with the dry film or the cured product. It is providing the printed wiring board by which a membrane | film | coat is formed.

In order to achieve the above object, according to the present invention, a photosensitive resin (hereinafter referred to as “photosensitive resin”) having a structure represented by the following general formula (I), a carboxyl group-containing resin, and a photopolymerization initiator An alkali-developable photo-curable resin composition is provided.

(Wherein R ¹ is a hydrogen atom or an organic group having 1 to 20 carbon atoms, which may be the same or different,
R ² represents at least one functional group selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an alkylene group having 1 to 10 carbon atoms, and a phenylene group,
R ³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms,
R ⁴ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms,
R ⁵ represents a hydrogen atom or a methyl group,
p represents an integer of 1 to 5, q represents an integer of 3 or more, m represents an integer of 1 to 4, and n represents an integer of 1 to 10. )

In a preferred embodiment, the photo-curable resin composition according to claim 1, wherein the photosensitive resin does not contain an acid and has a double bond equivalent of 200 or more and 400 or less.
The photosensitive resin is prepared by reacting a compound having three or more phenolic hydroxyl groups in one molecule with a cyclic ether compound or a cyclic carbonate compound, and reacting a compound having an ethylenically unsaturated group with the generated hydroxyl group. It is a photosensitive resin obtained in this way.
In this case, preferably, the compound having three or more phenolic hydroxyl groups in one molecule is a compound having a phenolic hydroxyl group having a softening point of room temperature or higher, and the compound having the ethylenically unsaturated group. Is preferably methacrylic acid.

In a preferred embodiment, it further contains a thermosetting component, and preferably further contains a colorant. Such a photocurable resin composition, particularly a photocurable thermosetting resin composition containing a thermosetting component, can be suitably used as a solder resist.
Further, according to the present invention, the photocurable resin composition obtained by applying and drying the photocurable resin composition on a carrier film, the photocurable resin composition or the dry film is cured. In addition, a cured product obtained by photo-curing on copper, and a cured product obtained by photo-curing in a pattern are also provided.

Furthermore, according to the present invention, there is also provided a printed wiring board characterized by having a cured film obtained by photocuring the photocurable resin composition or dry film in a pattern and then thermosetting. *

In the photocurable resin composition of the present invention, as the photosensitive resin, the photosensitive resin including the structure represented by the general formula (I) does not particularly contain an acid, and the double bond equivalent is 200 or more and 400 or less. It is characterized by.

In addition, this photosensitive resin reacts a compound having three or more phenolic hydroxyl groups in one molecule with a cyclic ether compound or a cyclic carbonate compound, and reacts a compound having an ethylenically unsaturated group with the generated hydroxyl group. Excellent dryness to touch of dry coating, high sensitivity and flexibility, excellent solder heat resistance, electroless gold plating resistance, moisture resistance, electrical insulation, etc., especially high insulation resistance at high temperature humidification A cured film can be formed. Moreover, since the carboxyl group-containing resin is contained together with the photosensitive resin, the resulting photocurable resin composition can be developed with an alkaline aqueous solution.

Therefore, the photocurable resin composition of the present invention can be advantageously applied to the formation of a cured film such as a solder resist of a printed wiring board or a flexible printed wiring board.

Hereinafter, embodiments of the present invention will be described.
As described above, the photocurable resin composition of the present invention is characterized in that a photosensitive resin including the structure represented by the general formula (I) is used as the photosensitive resin.

According to the study by the present inventors, by containing a photosensitive resin containing the structure represented by the general formula (I), the dry photocoating resin composition obtained has excellent dryness to touch. Moreover, the cured film has a high insulation resistance value under high-temperature humidification conditions, and it has been found that the occurrence of ion migration is not a problem for a long time as compared with the case where the photosensitive resin is not contained. In particular, a hydroxyl group produced by reacting a cyclic ether compound or a cyclic carbonate compound with a compound having no acid, having a double bond equivalent of 200 or more and 400 or less, and having 3 or more phenolic hydroxyl groups in one molecule. It has been found that the sensitivity is improved when a photosensitive resin obtained by reacting a compound having an ethylenically unsaturated group with is used. Surprisingly, it was also obtained that the elongation percentage of the cured film was improved as the amount of the photosensitive resin used was increased. Therefore, good results were obtained with respect to crack resistance, flexibility and punching resistance of the cured film, but this was surprising and unexpected.

The photosensitive resin contains three or more structures represented by the general formula (I) in one molecule (q ≧ 3). When the structure represented by the general formula (I) is 2 or less in one molecule, high sensitivity which is one of the objects of the present invention cannot be achieved, and in particular, in the case of a solder resist, the surface curability is inferior. As a result, the electrical insulation during high temperature humidification is low, and ion migration may occur. Similarly, a double bond equivalent of 200 or less cannot be structurally, and when it is 400 or more, high sensitivity cannot be achieved, and furthermore, the electrical insulation and ion migration properties are poor, so the double bond equivalent is 200 or more. 400 or less is preferable.

The photosensitive resin containing the structure represented by the general formula (I) may be synthesized by a conventionally known method, but preferably a compound having three or more phenolic hydroxyl groups in one molecule. A photosensitive resin obtained by reacting a cyclic ether compound or a cyclic carbonate compound and reacting the resulting alcoholic hydroxyl group with a compound having an ethylenically unsaturated group can be suitably used. Further, if the photosensitive resin obtained by reacting an alcoholic hydroxyl group with a compound having an ethylenically unsaturated group has three or more structures represented by the general formula (1), the alcoholic hydroxyl group may remain. .

Examples of the compound having three or more phenolic hydroxyl groups in one molecule include novolak type phenol resins. The novolak-type phenol resin is obtained by a condensation reaction between phenols and formaldehyde, and these reactions are usually performed in the presence of an acidic catalyst. Examples of the phenols used for the synthesis of the novolak type phenol resin include phenol, cresol, ethylphenol, propylphenol, butylphenol, hexylphenol, octylphenol, nonylphenol, phenylphenol, cumylphenol, bisphenol A, bisphenol F, and bixylenol. These may be used alone or in combination. Further, condensates of phenols and aromatic aldehydes having a phenolic hydroxyl group, poly-p-hydroxystyrene, 1-naphthol or condensates of 2-naphthol and aldehydes (ie, naphthol type novolak resin), 1, 2 -, 1,3-, 1,4-, 1,5-, 1,6-, 2,3-, 2,6-, 2,7-dihydroxynaphthalene and aldehydes, mononaphthol and the above Condensates of dihydroxynaphthalene and aldehydes, condensates of mono or dihydroxynaphthalene and xylylene glycols, adducts of mono or dihydroxynaphthalene and diene compounds, condensates of phenols and bis (methoxymethyl) biphenyl, etc. However, it is not limited to these. In particular, it is preferable to use a phenol resin having an average phenol nucleus number of 3 or more.

Among the cyclic ether compound or the cyclic carbonate compound, examples of the cyclic ether compound include ethylene oxide, propylene oxide, 1,2-butylene oxide, trimethylene oxide, tetrahydrofuran, and tetrahydropyran.

Also, examples of the cyclic carbonate compound include ethylene carbonate and / or propylene carbonate. Particularly preferred are ethylene oxide and propylene oxide.

As the compound having an ethylenically unsaturated group, acrylic acid and methacrylic acid are preferable, and methacrylic acid is particularly preferable from the viewpoint of alkali resistance and electrical insulation. It is clear that the photosensitive resin using methacrylic acid has a high sensitivity, particularly excellent alkali resistance and electrical characteristics, and gives a cured product having a high insulation resistance value at high temperature humidification. There was no surprising result.

The amount of the photosensitive resin is, for example, in the range of 1 to 100 parts by weight, preferably 5 to 60 parts by weight, more preferably 10 to 40 parts by weight with respect to 100 parts by weight of the carboxyl group-containing resin. When there are too many compounding quantities of photosensitive resin than the said range, alkali developability will fall and it will become easy to produce a development residue. On the other hand, when the amount is 1 part by mass or less, the image forming ability is impaired.

As the carboxyl group-containing resin, various conventionally known carboxyl group-containing resins having a carboxyl group in the molecule for the purpose of imparting alkali developability can be used. In particular, a carboxyl group-containing photosensitive resin having an ethylenically unsaturated double bond in the molecule is more preferable in terms of photocurability and development resistance. And the unsaturated double bond is preferably derived from acrylic acid, methacrylic acid or derivatives thereof.

As specific examples of the carboxyl group-containing resin, the following compounds (any of oligomers and polymers) are preferable.
(1) A carboxyl group-containing resin obtained by copolymerization of an unsaturated carboxylic acid such as (meth) acrylic acid and an unsaturated group-containing compound such as styrene, α-methylstyrene, lower alkyl (meth) acrylate, and isobutylene.
(2) Diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, and aromatic diisocyanates; carboxyl group-containing dialcohol compounds such as dimethylolpropionic acid and dimethylolbutanoic acid, polycarbonate polyols, and polyethers A carboxyl group-containing urethane resin by a polyaddition reaction of a diol compound such as a polyol, a polyester-based polyol, a polyolefin-based polyol, an acrylic polyol, a bisphenol A-based alkylene oxide adduct diol, a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.
(3) Diisocyanate and bifunctional epoxy resin such as bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bixylenol type epoxy resin, biphenol type epoxy resin ( Photosensitive carboxyl group-containing urethane resin by polyaddition reaction of (meth) acrylate or its modified partial anhydride, carboxyl group-containing dialcohol compound and diol compound.
(4) During the synthesis of the resin of the above (2) or (3), a compound having one hydroxyl group and one or more (meth) acryl groups in the molecule such as hydroxyalkyl (meth) acrylate is added, and the terminal ( Photosensitive carboxyl group-containing urethane resin that has been meta-acrylated.
(5) During the synthesis of the resin of the above (2) or (3), one isocyanate group and one or more (meth) acryl groups are added in the molecule, such as an equimolar reaction product of isophorone diisocyanate and pentaerythritol triacrylate. The photosensitive carboxyl group-containing urethane resin which added the compound which has and was terminally (meth) acrylated.
(6) A photosensitive carboxyl group obtained by reacting a bifunctional or higher polyfunctional (solid) epoxy resin as described later with (meth) acrylic acid and adding a dibasic acid anhydride to the hydroxyl group present in the side chain. Containing resin.
(7) A polyfunctional epoxy resin obtained by epoxidizing a hydroxyl group of a bifunctional (solid) epoxy resin as described later with epichlorohydrin is reacted with (meth) acrylic acid, and a dibasic acid anhydride is added to the resulting hydroxyl group. Added photosensitive carboxyl group-containing resin.
(8) A carboxyl group-containing polyester resin obtained by reacting a difunctional oxetane resin as described later with a dicarboxylic acid and adding a dibasic acid anhydride to the resulting primary hydroxyl group.
(9) A photosensitive carboxyl group-containing resin obtained by adding a compound having one epoxy group and one or more (meth) acryl groups in one molecule to the resins (1) to (8).
In addition, in this specification, (meth) acrylate is a term that collectively refers to acrylate, methacrylate, and mixtures thereof, and the same applies to other similar expressions.
Since the carboxyl group-containing resin as described above has many free carboxyl groups in the side chain of the backbone polymer, development with a dilute alkaline aqueous solution is possible.

The acid value of the carboxyl group-containing resin is in the range of 40 to 200 mgKOH / g, and more preferably in the range of 45 to 120 mgKOH / g. When the acid value of the carboxyl group-containing resin is less than 40 mgKOH / g, alkali development becomes difficult. On the other hand, when the acid value exceeds 200 mgKOH / g, dissolution of the exposed area by the developer proceeds and the line becomes thinner than necessary. In some cases, the exposed portion and the unexposed portion are not distinguished from each other by dissolution and peeling with a developer, which makes it difficult to draw a normal resist pattern.

The weight-average molecular weight of the carboxyl group-containing resin varies depending on the resin skeleton, but is generally within the range of 2,000 to 150,000, more preferably 5,000 to 100,000. When the weight average molecular weight is less than 2,000, tack-free performance may be inferior, the moisture resistance of the coated film after exposure may be poor, film thickness may be reduced during development, and resolution may be greatly inferior. On the other hand, when the weight average molecular weight exceeds 150,000, developability may be remarkably deteriorated, and storage stability may be inferior.

The amount of such a carboxyl group-containing resin is 20 to 60% by mass, preferably 30 to 50% by mass in the total composition. When the amount of the carboxyl group-containing resin is less than the above range, the film strength is lowered, which is not preferable. On the other hand, when the amount is larger than the above range, the viscosity of the composition is increased or the coating property is lowered, which is not preferable.
These carboxyl group-containing resins can be used without being limited to those listed above, and can be used singly or in combination.

Examples of the photopolymerization initiator include an oxime ester photopolymerization initiator having a group represented by the following general formula (II), and an α-aminoacetophenone photopolymerization initiator having a group represented by the following general formula (III). It is preferable to use at least one photopolymerization initiator selected from the group consisting of acylphosphine oxide photopolymerization initiators having a group represented by the following formula (IV).

(Wherein R ⁶ represents a hydrogen atom, a phenyl group (which may be substituted with an alkyl group having 1 to 6 carbon atoms, a phenyl group or a halogen atom), an alkyl group having 1 to 20 carbon atoms (one or more). Or a cycloalkyl group having 5 to 8 carbon atoms, an alkanoyl group having 2 to 20 carbon atoms, or benzoyl. A group (which may be substituted with an alkyl group having 1 to 6 carbon atoms or a phenyl group),
R ⁷ is a phenyl group (which may be substituted with an alkyl group having 1 to 6 carbon atoms, a phenyl group or a halogen atom), or an alkyl group having 1 to 20 carbon atoms (which may be substituted with one or more hydroxyl groups). It may have one or more oxygen atoms in the middle of the alkyl chain), a cycloalkyl group having 5 to 8 carbon atoms, an alkanoyl group having 2 to 20 carbon atoms or a benzoyl group (having 1 to 6 carbon atoms) Which may be substituted with an alkyl group or a phenyl group of
R ⁸ and R ⁹ each independently represents an alkyl group having 1 to 12 carbon atoms or an arylalkyl group,
R ¹⁰ and R ¹¹ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a cyclic alkyl ether group in which two are bonded,
R ¹² and R ¹³ are each independently a linear or branched alkyl group having 1 to 10 carbon atoms, a cyclohexyl group, a cyclopentyl group, an aryl group, or an aryl substituted with a halogen atom, an alkyl group or an alkoxy group Wherein one of R ¹² and R ¹³ may represent an R—C (═O) — group (where R is a hydrocarbon group having 1 to 20 carbon atoms). )

The oxime ester photopolymerization initiator having a group represented by the general formula (II) is preferably 2- (acetyloxyiminomethyl) thioxanthen-9-one represented by the following formula (V): The compound represented by the following general formula (VI) and the compound represented by the following general formula (VII) are mentioned.

(Wherein R ¹⁴ represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, a cyclopentyl group, a cyclohexyl group, a phenyl group, a benzyl group, a benzoyl group, an alkanoyl group having 2 to 12 carbon atoms, or 2 carbon atoms) To 12 alkoxycarbonyl groups (when the alkyl group constituting the alkoxyl group has 2 or more carbon atoms, the alkyl group may be substituted with one or more hydroxyl groups, and one or more oxygen atoms in the middle of the alkyl chain) Or a phenoxycarbonyl group,
R ¹⁵ and R ¹⁷ are each independently a phenyl group (which may be substituted with an alkyl group having 1 to 6 carbon atoms, a phenyl group or a halogen atom), an alkyl group having 1 to 20 carbon atoms (one or more Which may be substituted with a hydroxyl group and may have one or more oxygen atoms in the middle of the alkyl chain), a cycloalkyl group having 5 to 8 carbon atoms, an alkanoyl group having 2 to 20 carbon atoms or a benzoyl group (Which may be substituted with an alkyl group having 1 to 6 carbon atoms or a phenyl group),
R ¹⁶ is a hydrogen atom, a phenyl group (which may be substituted with an alkyl group having 1 to 6 carbon atoms, a phenyl group or a halogen atom), or an alkyl group having 1 to 20 carbon atoms (substituted with one or more hydroxyl groups). And may have one or more oxygen atoms in the middle of the alkyl chain), a cycloalkyl group having 5 to 8 carbon atoms, an alkanoyl group having 2 to 20 carbon atoms or a benzoyl group (having a carbon number). Optionally substituted with 1 to 6 alkyl groups or phenyl groups). )

(Wherein R ¹⁸ , R ¹⁹ and R ²⁴ each independently represents an alkyl group having 1 to 12 carbon atoms,
R ²⁰ , R ²¹ , R ²² and R ²³ each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms,
M represents O, S or NH;
x and y each independently represents an integer of 0 to 5. )

Among the oxime ester photopolymerization initiators, 2- (acetyloxyiminomethyl) thioxanthen-9-one represented by the general formula (V) and a compound represented by the formula (VI) are more preferable. Examples of commercially available products include CGI-325, Irgacure OXE01, Irgacure OXE02 manufactured by Ciba Specialty Chemicals, and N-1919 manufactured by ADEKA. These oxime ester photopolymerization initiators can be used alone or in combination of two or more.

Examples of the α-aminoacetophenone photopolymerization initiator having the group represented by the general formula (III) include 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropanone-1, 2- Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) ) Phenyl] -1-butanone, N, N-dimethylaminoacetophenone and the like. Examples of commercially available products include Irgacure 907, Irgacure 369, and Irgacure 379 manufactured by Ciba Specialty Chemicals.

Examples of the acylphosphine oxide photopolymerization initiator having a group represented by the general formula (IV) include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine. And oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, and the like. Examples of commercially available products include Lucilin TPO manufactured by BASF and Irgacure 819 manufactured by Ciba Specialty Chemicals.

The blending amount of such a photopolymerization initiator is suitably in the range of 0.01 to 30 parts by mass, preferably 0.5 to 15 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. When the blending amount of the photopolymerization initiator is less than 0.01 parts by mass, the photocurability on copper is insufficient, and the coating film is peeled off or the coating film properties such as chemical resistance are deteriorated. . On the other hand, if it exceeds 30 parts by mass, light absorption on the surface of the solder resist coating film of the photopolymerization initiator becomes violent and the deep-part curability tends to decrease, which is not preferable.

In the case of the oxime ester photopolymerization initiator having a group represented by the formula (II), the blending amount is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. More preferably, the range of 0.01 to 5 parts by mass is desirable.

Other photopolymerization initiators, photoinitiator assistants and sensitizers that can be suitably used in the photocurable resin composition of the present invention include benzoin compounds, acetophenone compounds, anthraquinone compounds, thioxanthone compounds, ketal compounds, and benzophenones. A compound, a xanthone compound, a tertiary amine compound, etc. can be mentioned.

Specific examples of the benzoin compound include benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether.
Specific examples of the acetophenone compound include acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, and 1,1-dichloroacetophenone.
Specific examples of the anthraquinone compound include 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, and 1-chloroanthraquinone.
Specific examples of the thioxanthone compound include, for example, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, and 2,4-diisopropylthioxanthone.
Specific examples of the ketal compound include acetophenone dimethyl ketal and benzyl dimethyl ketal.
Specific examples of the benzophenone compound include, for example, benzophenone, 4-benzoyldiphenyl sulfide, 4-benzoyl-4′-methyldiphenyl sulfide, 4-benzoyl-4′-ethyldiphenyl sulfide, 4-benzoyl-4′-propyldiphenyl. Sulfide.

Specific examples of the tertiary amine compound include, for example, an ethanolamine compound, a compound having a dialkylaminobenzene structure, such as 4,4′-dimethylaminobenzophenone (Nisso Cure MABP manufactured by Nippon Soda Co., Ltd.), 4,4′-diethylamino. Dialkylamino benzophenones such as benzophenone (EAB manufactured by Hodogaya Chemical Co.), and dialkylamino groups such as 7- (diethylamino) -4-methyl-2H-1-benzopyran-2-one (7- (diethylamino) -4-methylcoumarin) Contained coumarin compound, ethyl 4-dimethylaminobenzoate (Kayacure EPA, Nippon Kayaku Co., Ltd.), ethyl 2-dimethylaminobenzoate (Quantacure DMB, International Bio-Synthetics), 4-dimethylaminobenzoic acid n-butoxy) ethyl (Quantacure BEA, manufactured by International Bio-Synthetics), p-dimethylaminobenzoic acid isoamyl ethyl ester (Kayacure DMBI manufactured by Nippon Kayaku Co., Ltd.), 2-ethylhexyl 4-dimethylaminobenzoic acid (Van Dyk) Esol 507), 4,4′-diethylaminobenzophenone (EAB manufactured by Hodogaya Chemical Co., Ltd.).

Among the aforementioned compounds, thioxanthone compounds and tertiary amine compounds are preferable. The composition of the present invention preferably contains a thioxanthone compound from the viewpoint of deep curability, and among them, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone A thioxanthone compound such as

The amount of such a thioxanthone compound is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, with respect to 100 parts by mass of the carboxyl group-containing resin. If the amount of the thioxanthone compound is too large, the thick film curability is lowered and the cost of the product is increased, which is not preferable.

As the tertiary amine compound, a compound having a dialkylaminobenzene structure is preferable, among which a dialkylaminobenzophenone compound and a dialkylamino group-containing coumarin compound having a maximum absorption wavelength of 350 to 410 nm are particularly preferable. As the dialkylaminobenzophenone compound, 4,4'-diethylaminobenzophenone is preferable because of its low toxicity. A dialkylamino group-containing coumarin compound having a maximum absorption wavelength of 350 to 410 nm has a maximum absorption wavelength in the ultraviolet region, so that it is less colored and uses a color pigment as well as a colorless and transparent photosensitive composition. A colored solder resist film reflecting the color can be provided. In particular, 7- (diethylamino) -4-methyl-2H-1-benzopyran-2-one is preferable because it exhibits an excellent sensitizing effect on laser light having a wavelength of 400 to 410 nm.

The blending amount of such a tertiary amine compound is preferably 0.1 to 20 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. When the amount of the tertiary amine compound is less than 0.1 parts by mass, a sufficient sensitizing effect tends not to be obtained. On the other hand, when the amount exceeds 20 parts by mass, light absorption on the surface of the dry solder resist coating film by the tertiary amine compound becomes intense, and the deep curability tends to decrease.

These photopolymerization initiators, photoinitiator assistants, and sensitizers can be used alone or as a mixture of two or more.

The total amount of such photopolymerization initiator, photoinitiator assistant, and sensitizer is preferably in the range of 35 parts by mass or less with respect to 100 parts by mass of the carboxyl group-containing resin. When it exceeds 35 parts by mass, the deep curability tends to decrease due to light absorption.

In the photocurable resin composition of the present invention, known and commonly used N-phenylglycines, phenoxyacetic acids, thiophenoxyacetic acids, mercaptothiazole and the like can be used as chain transfer agents in order to improve sensitivity. Specific examples of chain transfer agents include, for example, chain transfer agents having a carboxyl group such as mercaptosuccinic acid, mercaptoacetic acid, mercaptopropionic acid, methionine, cysteine, thiosalicylic acid and derivatives thereof; mercaptoethanol, mercaptopropanol, mercaptobutanol Chain transfer agents having a hydroxyl group such as 1-butanethiol, butyl-3-mercaptopropionate, methyl-3-mercaptopropionate, 2,2 -(Ethylenedioxy) diethanethiol, ethanethiol, 4-methylbenzenethiol, dodecyl mercaptan, propanethiol, butanethiol, pentanethiol, 1-octanethiol, cyclo Ntanchioru, cyclohexane thiol, thioglycerol, 4,4-thiobisbenzenethiol like.

Further, examples of the heterocyclic compound having a mercapto group acting as a chain transfer agent include mercapto-4-butyrolactone (also known as 2-mercapto-4-butanolide), 2-mercapto-4-methyl-4-butyrolactone, 2-mercapto. -4-ethyl-4-butyrolactone, 2-mercapto-4-butyrothiolactone, 2-mercapto-4-butyrolactam, N-methoxy-2-mercapto-4-butyrolactam, N-ethoxy-2-mercapto-4- Butyrolactam, N-methyl-2-mercapto-4-butyrolactam, N-ethyl-2-mercapto-4-butyrolactam, N- (2-methoxy) ethyl-2-mercapto-4-butyrolactam, N- (2-ethoxy) Ethyl-2-mercapto-4-butyrolactam, 2-mercapto-5 Lerolactone, 2-mercapto-5-valerolactam, N-methyl-2-mercapto-5-valerolactam, N-ethyl-2-mercapto-5-valerolactam, N- (2-methoxy) ethyl-2-mercapto- Examples include 5-valerolactam, N- (2-ethoxy) ethyl-2-mercapto-5-valerolactam, and 2-mercapto-6-hexanolactam.

In particular, as a heterocyclic compound having a mercapto group that is a chain transfer agent that does not impair the developability of the photocurable resin composition, mercaptobenzothiazole, 3-mercapto-4-methyl-4H-1,2,4- Triazole, 5-methyl-1,3,4-thiadiazole-2-thiol and 1-phenyl-5-mercapto-1H-tetrazole are preferred. These chain transfer agents can be used alone or in combination of two or more.

A thermosetting resin can be added to the photocurable resin composition of the present invention in order to impart heat resistance. Examples of thermosetting components used in the present invention include amine resins such as melamine resins and benzoguanamine resins, block isocyanate compounds, cyclocarbonate compounds, polyfunctional epoxy compounds, polyfunctional oxetane compounds, episulfide resins, melamine derivatives, and the like. A curable resin can be used. Particularly preferred is a thermosetting component having two or more cyclic ether groups and / or cyclic thioether groups (hereinafter abbreviated as cyclic (thio) ether groups) in the molecule.

Such a thermosetting component having two or more cyclic (thio) ether groups in the molecule is either one of the three-, four- or five-membered cyclic ether groups in the molecule, or the cyclic thioether group, or two of them. A compound having at least two epoxy groups in the molecule, that is, a polyfunctional epoxy compound, a compound having at least two oxetanyl groups in the molecule, that is, a polyfunctional compound. Examples include oxetane compounds, compounds having two or more thioether groups in the molecule, that is, episulfide resins.

Examples of the polyfunctional epoxy compound include jER828, jER834, jER1001, and jER1004 manufactured by Japan Epoxy Resin, Epicron 840, Epicron 850, Epicron 1050, Epicron 2055, and Epoto manufactured by Tohto Kasei Co., Ltd. YD-011, YD-013, YD-127, YD-128, D.C. E. R. 317, D.E. E. R. 331, D.D. E. R. 661, D.E. E. R. 664, Ciba Specialty Chemicals' Araldide 6071, Araldide 6084, Araldide GY250, Araldide GY260, Sumitomo Chemical Industries Sumi-Epoxy ESA-011, ESA-014, ELA-115, ELA-128, Asahi Kasei Corporation A. E. R. 330, A.I. E. R. 331, A.I. E. R. 661, A.I. E. R. Bisphenol A type epoxy resin such as 664 (all trade names); jERYL903 manufactured by Japan Epoxy Resin Co., Epicron 152, Epicron 165 manufactured by Dainippon Ink and Chemicals, Epototo YDB-400, YDB-500 manufactured by Tohto Kasei Co., Ltd. D. Chemicals manufactured by Dow Chemical Company. E. R. 542, Araldide 8011 manufactured by Ciba Specialty Chemicals, Sumi-epoxy ESB-400, ESB-700 manufactured by Sumitomo Chemical Co., Ltd., and A.D. E. R. 711, A.I. E. R. 714 (both trade names) brominated epoxy resin; jER152, jER154 manufactured by Japan Epoxy Resin, D.C. E. N. 431, D.D. E. N. 438, Epicron N-730, Epicron N-770, Epicron N-865 manufactured by Dainippon Ink and Chemicals, Epototo YDCN-701, YDCN-704 manufactured by Tohto Kasei Co., Ltd., Araldide ECN1235 manufactured by Ciba Specialty Chemicals, Araldide ECN1273, Araldide ECN1299, Araldide XPY307, EPPN-201, EOCN-1025, EOCN-1020, EOCN-104S, RE-306 manufactured by Nippon Kayaku Co., Ltd., Sumi-epoxy ESCN-195X, ESCN- manufactured by Sumitomo Chemical Co., Ltd. 220, manufactured by Asahi Kasei Corporation. E. R. Novolak type epoxy resins such as ECN-235, ECN-299, etc. (both trade names); Epicron 830 manufactured by Dainippon Ink & Chemicals, jER807 manufactured by Japan Epoxy Resin, Epototo YDF-170 manufactured by Toto Kasei Co., YDF- 175, YDF-2004, Araldide XPY306 manufactured by Ciba Specialty Chemicals (both trade names), bisphenol F type epoxy resin; Etoto ST-2004, ST-2007, ST-3000 manufactured by Toto Kasei Hydrogenated bisphenol A type epoxy resin such as product name); jER604 manufactured by Japan Epoxy Resin, Epototo YH-434 manufactured by Tohto Kasei Co., Ltd., Araldide MY720 manufactured by Ciba Specialty Chemicals, Sumitomo Chemical Industries Epoxy ELM-120 etc. ( Glycidylamine type epoxy resin (trade name); Hydantoin type epoxy resin such as Araldide CY-350 (trade name) manufactured by Ciba Specialty Chemicals; Celoxide 2021 manufactured by Daicel Chemical Industries, Ciba Specialty Chemicals Alicyclic epoxy resins such as Araldide CY175, CY179, etc. (both trade names) manufactured by YL-933 manufactured by Japan Epoxy Resin Co., Ltd. E. N. , EPPN-501, EPPN-502, etc. (all trade names) trihydroxyphenylmethane type epoxy resin; Japan Epoxy Resin YL-6056, YX-4000, YL-6121 (all trade names), etc. Xylenol type or biphenol type epoxy resins or mixtures thereof; bisphenols such as EBPS-200 manufactured by Nippon Kayaku Co., Ltd., EPX-30 manufactured by Asahi Denka Kogyo Co., Ltd., EXA-1514 manufactured by Dainippon Ink & Chemicals, Inc. S type epoxy resin; bisphenol A novolac type epoxy resin such as jER157S (trade name) manufactured by Japan Epoxy Resin; jERYL-931 manufactured by Japan Epoxy Resin, Araldide 163 manufactured by Ciba Specialty Chemicals, etc. Name) tetraphenylolethane type Xylon resin; Araldide PT810 manufactured by Ciba Specialty Chemicals, TEPIC manufactured by Nissan Chemical Industries, Ltd. (both trade names), heterocyclic epoxy resins; Diglycidyl phthalate resin such as Bremer DGT manufactured by Nippon Oil &Fats; Toto Kasei Tetraglycidylxylenoylethane resin such as ZX-1063 manufactured by Nippon Steel; containing naphthalene groups such as ESN-190 and ESN-360 manufactured by Nippon Steel Chemical Co., Ltd. and HP-4032, EXA-4750 and EXA-4700 manufactured by Dainippon Ink & Chemicals, Inc. Epoxy resin; Epoxy resin having a dicyclopentadiene skeleton such as HP-7200 and HP-7200H manufactured by Dainippon Ink &Chemicals; Glycidyl methacrylate copolymer epoxy resin such as CP-50S and CP-50M manufactured by Nippon Oil &Fats; In addition, cyclohexylmaleimide and glycidyl Copolymerized epoxy resin of acrylate; epoxy-modified polybutadiene rubber derivative (for example, PB-3600 manufactured by Daicel Chemical Industries), CTBN-modified epoxy resin (for example, YR-102, YR-450 manufactured by Tohto Kasei Co., Ltd.), etc. However, it is not limited to these. These epoxy resins can be used alone or in combination of two or more. Among these, a novolac type epoxy resin, a heterocyclic epoxy resin, a bisphenol A type epoxy resin or a mixture thereof is particularly preferable.

Examples of the polyfunctional oxetane compound include bis [(3-methyl-3-oxetanylmethoxy) methyl] ether, bis [(3-ethyl-3-oxetanylmethoxy) methyl] ether, 1,4-bis [(3-methyl -3-Oxetanylmethoxy) methyl] benzene, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, (3-methyl-3-oxetanyl) methyl acrylate, (3-ethyl-3-oxetanyl) In addition to polyfunctional oxetanes such as methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate and oligomers or copolymers thereof, oxetane alcohol and novolak resin, Poly (p-hydroxystyrene), cardo-type bisphe Lumpur acids, calixarenes, calix resorcin arenes, or the like ethers of a resin having a hydroxyl group such as silsesquioxane and the like. In addition, a copolymer of an unsaturated monomer having an oxetane ring and an alkyl (meth) acrylate is also included.

Examples of the compound having two or more cyclic thioether groups in the molecule include bisphenol A type episulfide resin YL7000 manufactured by Japan Epoxy Resins. Moreover, episulfide resin etc. which replaced the oxygen atom of the epoxy group of the novolak-type epoxy resin with the sulfur atom using the same synthesis method can be used.

The amount of the thermosetting component having two or more cyclic (thio) ether groups in the molecule is preferably 0.6 to 2.5 equivalents relative to 1 equivalent of the carboxyl group of the carboxyl group-containing resin. More preferably, a range of 0.8 to 2.0 equivalents is appropriate. When the amount of the thermosetting component having two or more cyclic (thio) ether groups in the molecule is less than 0.6, carboxyl groups remain in the solder resist film, and heat resistance, alkali resistance, electrical insulation, etc. Is unfavorable because it decreases. On the other hand, when the amount exceeds 2.5 equivalents, the low molecular weight cyclic (thio) ether group remains in the dry coating film, which is not preferable because the strength of the coating film decreases.

In addition, a compound having two or more isocyanate groups or blocked isocyanate groups in one molecule can be added to the photocurable resin composition of the present invention as a thermosetting component. Such a compound having two or more isocyanate groups or blocked isocyanate groups in one molecule is a compound having two or more isocyanate groups in one molecule, that is, a polyisocyanate compound, or two in one molecule. Examples thereof include compounds having the above blocked isocyanate groups, that is, blocked isocyanate compounds.

As the polyisocyanate compound, for example, aromatic polyisocyanate, aliphatic polyisocyanate or alicyclic polyisocyanate is used. Specific examples of the aromatic polyisocyanate include 4,4′-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, naphthalene-1,5-diisocyanate, o-xylylene diisocyanate, m- Examples include xylylene diisocyanate and 2,4-tolylene dimer. Specific examples of the aliphatic polyisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, 4,4-methylenebis (cyclohexyl isocyanate), and isophorone diisocyanate. Specific examples of the alicyclic polyisocyanate include bicycloheptane triisocyanate. In addition, adduct bodies, burette bodies, and isocyanurate bodies of the isocyanate compounds listed above may be mentioned.

The blocked isocyanate group contained in the blocked isocyanate compound is a group in which the isocyanate group is protected by reaction with a blocking agent and temporarily deactivated. When heated to a predetermined temperature, the blocking agent is dissociated to produce isocyanate groups.

As the blocked isocyanate compound, an addition reaction product of an isocyanate compound and an isocyanate blocking agent is used. Examples of the isocyanate compound that can react with the blocking agent include isocyanurate type, biuret type, and adduct type. As this isocyanate compound, aromatic polyisocyanate, aliphatic polyisocyanate, or alicyclic polyisocyanate is used, for example. Specific examples of the aromatic polyisocyanate include 4,4′-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, naphthalene-1,5-diisocyanate, o-xylylene diisocyanate, m- Examples include xylylene diisocyanate and 2,4-tolylene dimer. Specific examples of the aliphatic polyisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, 4,4-methylenebis (cyclohexyl isocyanate), and isophorone diisocyanate. Specific examples of the alicyclic polyisocyanate include bicycloheptane triisocyanate.

Examples of the isocyanate blocking agent include phenolic blocking agents such as phenol, cresol, xylenol, chlorophenol and ethylphenol; lactam blocking agents such as ε-caprolactam, δ-palerolactam, γ-butyrolactam and β-propiolactam; Active methylene blocking agents such as ethyl acetoacetate and acetylacetone; methanol, ethanol, propanol, butanol, amyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, propylene glycol monomethyl ether, benzyl Ether, methyl glycolate, butyl glycolate, diacetone alcohol, lactic acid Alcohol-based blocking agents such as chill and ethyl lactate; oxime-based blocking agents such as formaldehyde oxime, acetoaldoxime, acetoxime, methylethyl ketoxime, diacetyl monooxime, cyclohexane oxime; butyl mercaptan, hexyl mercaptan, t-butyl mercaptan, thiophenol, Mercaptan block agents such as methylthiophenol and ethylthiophenol; Acid amide block agents such as acetic acid amide and benzamide; Imide block agents such as succinimide and maleic imide; Amines such as xylidine, aniline, butylamine and dibutylamine Blocking agents; imidazole blocking agents such as imidazole and 2-ethylimidazole; imine blocking agents such as methyleneimine and propyleneimine It is done.

The blocked isocyanate compound may be commercially available, for example, Sumidur BL-3175, BL-4165, BL-1100, BL-1265－, Desmodur TPLS-2957２９, TPLS-2062, manufactured by Sumitomo Bayer Urethane Co., Ltd. TPLS-2078, TPLS-2117, Desmotherm 2170, Desmotherm 2265, Coronate 2512, Coronate 2513, Coronate 2520, manufactured by Nippon Polyurethane Industry Co., Ltd. B-830, B-815, B-846, B-870 manufactured by Mitsui Takeda Chemical Co., Ltd. , B-874, B-882, TPA-B80E, 17B-60PX, E402-B80T (all trade names) manufactured by Asahi Kasei Chemicals Corporation. Sumijoules BL-3175 and BL-4265 are obtained using methyl ethyl oxime as a blocking agent.

The compounds having two or more isocyanate groups or blocked isocyanate groups in one molecule can be used singly or in combination of two or more.

The compounding amount of the compound having two or more isocyanate groups or blocked isocyanate groups in one molecule is 1 to 100 parts by mass, more preferably 2 parts per 100 parts by mass of the carboxyl group-containing resin. A proportion of up to 70 parts by weight is appropriate. When the amount is less than 1 part by mass, sufficient toughness of the coating film cannot be obtained, which is not preferable. On the other hand, when it exceeds 100 mass parts, storage stability falls and it is not preferable.

Furthermore, examples of the thermosetting component include melamine derivatives and benzoguanamine derivatives. Examples include methylol melamine compounds, methylol benzoguanamine compounds, methylol glycoluril compounds, and methylol urea compounds. Furthermore, the alkoxymethylated melamine compound, the alkoxymethylated benzoguanamine compound, the alkoxymethylated glycoluril compound and the alkoxymethylated urea compound have the methylol group of the respective methylolmelamine compound, methylolbenzoguanamine compound, methylolglycoluril compound and methylolurea compound. Obtained by conversion to an alkoxymethyl group. The type of the alkoxymethyl group is not particularly limited and can be, for example, a methoxymethyl group, an ethoxymethyl group, a propoxymethyl group, a butoxymethyl group, or the like. In particular, a melamine derivative having a formalin concentration which is friendly to the human body and the environment is preferably 0.2% or less.

Examples of these commercially available products include Cymel 300, 301, 303, 370, 325, 327, 701, 266, 267, 238, 1141, and 272 manufactured by Mitsui Cyanamid Co., Ltd. 202, 1156, 1158, 1158, 1123, 1170, 1174, UFR65, 300, Nikarak Mx-750, Mx-032, Mx-270, Mx made by Sanwa Chemical Co., Ltd. -280, Mx-290, Mx-706, Mx-708, Mx-40, Mx-31, Ms-11, Mw-30, Mw-30HM, Mw-390, Mw -100LM, Mw-750LM (trade name), etc. The said thermosetting component can be used individually or in combination of 2 or more types.

When using a thermosetting component having two or more cyclic (thio) ether groups in the molecule, it is preferable to contain a thermosetting catalyst. Examples of such thermosetting catalysts include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole. Imidazole derivatives such as 1- (2-cyanoethyl) -2-ethyl-4-methylimidazole; dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N -Amine compounds such as dimethylbenzylamine and 4-methyl-N, N-dimethylbenzylamine; hydrazine compounds such as adipic acid dihydrazide and sebacic acid dihydrazide; and phosphorus compounds such as triphenylphosphine. Examples of commercially available products include 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, 2P4MHZ (both trade names of imidazole compounds) manufactured by Shikoku Kasei Kogyo Co., Ltd., and U-CAT (registered by San Apro). Trademarks) 3503N, U-CAT3502T (all are trade names of blocked isocyanate compounds of dimethylamine), DBU, DBN, U-CATSA102, U-CAT5002 (all are bicyclic amidine compounds and salts thereof), and the like. In particular, it is not limited to these, as long as it is a thermosetting catalyst for epoxy resins or oxetane compounds, or a catalyst that promotes the reaction of epoxy groups and / or oxetanyl groups with carboxyl groups, either alone or in combination of two or more. Can be used. Guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino S-triazine derivatives such as -S-triazine / isocyanuric acid adducts and 2,4-diamino-6-methacryloyloxyethyl-S-triazine / isocyanuric acid adducts can also be used. A compound that also functions in combination with the thermosetting catalyst.

The blending amount of these thermosetting catalysts is sufficient in the usual quantitative ratio, for example, with respect to 100 parts by mass of the carboxyl group-containing resin or thermosetting component having two or more cyclic (thio) ether groups in the molecule. The amount is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15.0 parts by mass.

In the photocurable resin composition of the present invention, an adhesion promoter can be used in order to improve adhesion between layers or adhesion between the photosensitive resin layer and the substrate. Specific examples include benzimidazole, benzoxazole, benzthiazole, 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzthiazole, 3-morpholinomethyl-1-phenyl-triazole-2-thione. , 5-amino-3-morpholinomethyl-thiazole-2-thione, 2-mercapto-5-methylthio-thiadiazole, triazole, tetrazole, benzotriazole, carboxybenzotriazole, amino group-containing benzotriazole, silane coupling agent, etc. .

The compound having two or more ethylenically unsaturated groups in the molecule used in the photocurable resin composition of the present invention is photocured by irradiation with active energy rays to contain the ethylenically unsaturated group-containing carboxyl group. The resin is insolubilized in an alkaline aqueous solution, or helps insolubilization. Examples of such compounds include glycol diacrylates such as ethylene glycol, methoxytetraethylene glycol, polyethylene glycol, and propylene glycol; hexanediol, trimethylolpropane, pentaerythritol, dipentaerythritol, tris-hydroxyethyl isocyanurate, and the like. Polyhydric acrylates such as polyhydric alcohols or their ethylene oxide adducts or propylene oxide adducts; Phenoxy acrylate, bisphenol A diacrylate, and polyhydric acrylates such as ethylene oxide adducts or propylene oxide adducts of these phenols Glycerin diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycy Ethers, polyvalent acrylates of glycidyl ethers such as triglycidyl isocyanurate; and melamine acrylate, and / or the like each methacrylates corresponding to the acrylates.

Further, an epoxy acrylate resin obtained by reacting acrylic acid with a polyfunctional epoxy resin such as a cresol novolac type epoxy resin, and further, a hydroxy acrylate such as pentaerythritol triacrylate and a diisocyanate such as isophorone diisocyanate on the hydroxyl group of the epoxy acrylate resin. Examples thereof include an epoxy urethane acrylate compound obtained by reacting a half urethane compound. Such an epoxy acrylate resin can improve photocurability without deteriorating the touch drying property.

The compounding amount of the compound having two or more ethylenically unsaturated groups in the molecule is 5 to 100 parts by mass, more preferably 1 to 70 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. The ratio is appropriate. When the blending amount is less than 5 parts by mass, photocurability is lowered, and pattern formation becomes difficult by alkali development after irradiation with active energy rays, which is not preferable. On the other hand, when the amount exceeds 100 parts by mass, the solubility in an alkaline aqueous solution is lowered, and the coating film becomes brittle.

The photocurable resin composition of the present invention can contain a colorant. As the colorant, conventionally known colorants such as red, blue, green and yellow can be used, and any of pigments, dyes and dyes may be used. However, it is preferable not to contain a halogen from the viewpoint of reducing the environmental burden and affecting the human body.

Red colorant:
Examples of red colorants include monoazo, diazo, azo lake, benzimidazolone, perylene, diketopyrrolopyrrole, condensed azo, anthraquinone, and quinacridone. It is done.
Monoazo: Pigment Red 1, 2, 3, 4, 5, 6, 8, 9, 12, 14, 15, 16, 17, 21, 21, 22, 23, 31, 32, 112, 114, 146, 147, 151 , 170, 184, 187, 188, 193, 210, 245, 253, 258, 266, 267, 268, 269.
Disazo type: Pigment Red 37, 38, 41.
Monoazo lake system: Pigment Red 48: 1, 48: 2, 48: 3, 48: 4, 49: 1, 49: 2, 50: 1, 52: 1, 52: 2, 53: 1, 53: 2, 57 : 1, 58: 4, 63: 1, 63: 2, 64: 1,68.
Benzimidazolone series: Pigment Red 171, Pigment Red 175, Pigment Red 176, Pigment Red 185, Pigment Red 208.
Perylene: Solvent Red 135, Solvent Red 179, Pigment Red 123, Pigment Red 149, Pigment Red 166, Pigment Red 178, Pigment Red 179, Pigment Red 190, Pigment Red 24, Pigment Red 24,
Diketopyrrolopyrrole series: Pigment Red 254, Pigment Red 255, Pigment Red 264, Pigment Red 270, Pigment Red 272.
Condensed azo: Pigment Red 220, Pigment Red 144, Pigment Red 166, Pigment Red 214, Pigment Red 220, Pigment Red 221, and Pigment Red 242.
Anthraquinone series: Pigment Red 168, Pigment Red 177, Pigment Red 216, Solvent Red 149, Solvent Red 150, Solvent Red 52, Solvent Red 207.
Quinacridone series: Pigment Red 122, Pigment Red 202, Pigment Red 206, Pigment Red 207, Pigment Red 209.

Blue colorant:
Blue colorants include phthalocyanine-based and anthraquinone-based compounds, and pigment-based compounds classified as Pigment, specifically, the following color index (CI; The Society of Dyers and Colorists) (Issued by The Society of Dyers and Colorists) can be listed with numbers: Pigment Blue 15, Pigment Blue 15: 1, Pigment Blue 15: 2, Pigment Blue 15: 3, Pig: Blue 15: 3, Pig Pigment Blue 15: 6, Pigment Blue 16, and Pigment Blue 60.
Solvent Blue 35, Solvent Blue 63, Solvent Blue 68, Solvent Blue 70, Solvent Blue 83, Solvent Blue 87, Solvent Blue 94, Solvent Blue 97, Solvent Blue 97, SolBlu 97, SolBlu 97, SolBlu 97, SolBlu 97 Blue 70 or the like can be used. In addition to the above, a metal-substituted or unsubstituted phthalocyanine compound can also be used.

Green colorant:
Similarly, the green colorant includes phthalocyanine, anthraquinone, and perylene. Specifically, Pigment Green 7, Pigment Green 36, Solvent Green 3, Solvent Green 5, Solvent Green 20, Solvent Green 28, and the like are used. be able to. In addition to the above, a metal-substituted or unsubstituted phthalocyanine compound can also be used.

Yellow colorant:
Examples of yellow colorants include monoazo, disazo, condensed azo, benzimidazolone, isoindolinone, anthraquinone, and the like.
Anthraquinone series: Solvent Yellow 163, Pigment Yellow 24, Pigment Yellow 108, Pigment Yellow 193, Pigment Yellow 147, Pigment Yellow 199, Pigment Yellow 202.
Isoindolinone series: Pigment Yellow 110, Pigment Yellow 109, Pigment Yellow 139, Pigment Yellow 179, Pigment Yellow 185.
Condensed azo type: Pigment Yellow 93, Pigment Yellow 94, Pigment Yellow 95, Pigment Yellow 128, Pigment Yellow 155, Pigment Yellow 166, Pigment Yellow 180.
Benzimidazolone series: Pigment Yellow 120, Pigment Yellow 151, Pigment Yellow 154, Pigment Yellow 156, Pigment Yellow 175, Pigment Yellow 181.
Monoazo type: Pigment Yellow 1, 2, 3, 4, 5, 6, 9, 10, 12, 61, 62, 62: 1, 65, 73, 74, 75, 97, 100, 104, 105, 111, 116 167, 168, 169, 182, 183.
Disazo: Pigment Yellow 12, 13, 14, 16, 17, 55, 63, 81, 83, 87, 126, 127, 152, 170, 172, 174, 176, 188, 198.

In addition, for the purpose of adjusting the color tone, a colorant such as purple, orange, brown, or black may be added.
Specifically, Pigment Violet 19, 23, 29, 32, 36, 38, 42, Solvent Violet 13, 36, CI Pigment Orange 1, C.I. Pigment Orange 5, C.I. Pigment Orange 13, CI Pigment Orange 14, CI Pigment Orange 16, CI Pigment Orange 17, CI Pigment Orange 24, CI Pigment Orange 34, CI Pigment Orange 36 CI Pigment Orange 38, C.I. Pigment Orange 40, C.I. Pigment Orange 43, C.I. Pigment Orange 46, C.I. Pigment Orange 49, C.I. Pigment Orange 51, C. CI Pigment Orange 61, CI Pigment Orange 63, CI Pigment Orange 64, CI Pigment Orange Orange 71, C.I. Pigment Orange 73, C.I. Pigment Brown 23, C.I. Pigment Brown 25, C.I. Pigment Black 1, there is C.I. Pigment Black 7 and the like.

The blending ratio of the colorant as described above is not particularly limited, but is preferably 0 to 10 parts by weight, particularly preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of the carboxyl group-containing resin. It is enough.

In many polymer materials, once oxidation starts, oxidative degradation occurs successively in a chain, resulting in functional degradation of the polymer material, so that the photocurable resin composition of the present invention prevents oxidation, (1) radical scavengers that invalidate the generated radicals and / or (2) peroxide decomposers that decompose the generated peroxides into harmless substances and prevent the generation of new radicals Antioxidants can be added.

Specific examples of antioxidants that act as radical scavengers include hydroquinone, 4-tert-butylcatechol, 2-t-butylhydroquinone, hydroquinone monomethyl ether, 2,6-di-t-butyl-p-cresol, 2,2-methylene-bis- (4-methyl-6-tert-butylphenol), 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2 , 4,6-Tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, 1,3,5-tris (3 ′, 5′di-tert-butyl-4-hydroxybenzyl) -S -Phenol compounds such as triazine-2,4,6- (1H, 3H, 5H) trione, quinone compounds such as metaquinone and benzoquinone, bis (2,2, And amine compounds such as 6,6-tetramethyl-4-piperidyl) -sebacate and phenothiazine.

The radical scavenger may be commercially available, for example, Adeka Stub AO-30, Adeka Stub AO-330, Adeka Stub AO-20, Adeka Stub LA-77, Adeka Stub LA-57, Adeka Stub LA-67, manufactured by Asahi Denka Co., Ltd. ADK STAB LA-68, ADK STAB LA-87 (both trade names), IRGANOX 1010, IRGANOX 1035, IRGANOX 1076, IRGANOX 1135, TINUVIN 111FDL, TINUVIN 144, TINUVIN 152, TINUVIN 29, TINTIN Any of these may be trade names).

Specific examples of the antioxidant that acts as a peroxide decomposer include phosphorus compounds such as triphenyl phosphite, pentaerythritol tetralauryl thiopropionate, dilauryl thiodipropionate, distearyl 3,3 ′. -Sulfur compounds such as thiodipropionate.

The peroxide decomposing agent may be commercially available, for example, Adeka Stub TPP manufactured by Asahi Denka Co., Ltd., Mark AO-412S manufactured by Adeka Argus Chemical, Sumitizer TPS manufactured by Sumitomo Chemical (both are trade names), and the like. Can be mentioned.

Said antioxidant can be used individually by 1 type or in combination of 2 or more types.
Since the polymer material absorbs light and thereby decomposes and deteriorates, the photocurable resin composition of the present invention is not limited to the above-described antioxidant, but an ultraviolet absorber in order to take measures against stabilization against ultraviolet rays. Can be used.

Examples of the ultraviolet absorber include benzophenone derivatives, benzoate derivatives, benzotriazole derivatives, triazine derivatives, benzothiazole derivatives, cinnamate derivatives, anthranilate derivatives, dibenzoylmethane derivatives, and the like. Specific examples of benzophenone derivatives include 2-hydroxy-4-methoxy-benzophenone 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2,2′-dihydroxy-4-methoxy. Specific examples of benzoate derivatives include 2-ethylhexyl salicylate, phenyl salicylate, p-tert-butylphenyl salicylate, 2,4-di-tert- Butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate and hexadecyl-3,5-di-tert-butyl-4-hydroxybenzoate, etc .; specific examples of benzotriazole derivatives include 2- ( 2'-Hydroxy-5'-t-butylphenol ) Benzotriazole, 2- (2′-hydroxy-5′-methylphenyl) enzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole and 2- (2 ′ -Hydroxy-3 ', 5'-di-tert-amylphenyl) benzotriazole; Examples of specific triazine derivatives include hydroxyphenyl triazine, bisethylhexyloxyphenol methoxyphenyl triazine, and the like.

Ultraviolet absorbers may be commercially available, for example, TINUVIN PS, TINUVIN 99-2, TINUVIN 109, TINUVIN 384-2, TINUVIN 900, TINUVIN 928, TINUVIN 1130, TINUVIN manufactured by Ciba Specialty Chemicals 400, TINUVIN 405, TINUVIN 460, TINUVIN 479 (all are trade names), and the like.

Said ultraviolet absorber can be used individually by 1 type or in combination of 2 or more types, Stabilization of the molding obtained from the photocurable resin composition of this invention by using together with the said antioxidant. Can be planned.

In the photocurable resin composition of the present invention, a filler can be blended as necessary in order to increase the physical strength of the coating film. As such a filler, known and commonly used inorganic or organic fillers can be used. In particular, barium sulfate, spherical silica and talc are preferably used. Furthermore, in order to obtain a white appearance and flame retardancy, metal hydroxides such as titanium oxide, metal oxide, and aluminum hydroxide can be used as extender pigment fillers. The blending amount of the filler is preferably 75% by mass or less, more preferably 0.1 to 60% by mass of the total amount of the composition. If the blending amount of the filler exceeds 75% by mass of the total amount of the composition, the viscosity of the insulating composition is increased, and the coating and moldability are lowered, and the cured product becomes brittle.

Furthermore, the photocurable resin composition of the present invention may use an organic solvent for the synthesis of the carboxyl group-containing resin and the preparation of the composition, or for adjusting the viscosity for application to a substrate or a carrier film. it can.

Examples of such organic solvents include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, petroleum solvents, and the like. More specifically, ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl Glycol ethers such as ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, triethylene glycol monoethyl ether; ethyl acetate, butyl acetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate , Esters such as propylene glycol butyl ether acetate; ethanol, propano , Ethylene glycol, alcohols such as propylene glycol; octane, aliphatic hydrocarbons decane; petroleum ether is petroleum naphtha, hydrogenated petroleum naphtha, and petroleum solvents such as solvent naphtha. Such organic solvents are used alone or as a mixture of two or more.

The photo-curable resin composition of the present invention may further comprise, as necessary, known and commonly used thermal polymerization inhibitors, known and commonly used thickeners such as finely divided silica, organic bentonite, and montmorillonite, silicone-based, fluorine-based, and polymer-based Known additives such as antifoaming agents and / or leveling agents such as silane coupling agents such as imidazole, thiazole and triazole, antioxidants, rust inhibitors and the like can be blended.

The thermal polymerization inhibitor can be used to prevent thermal polymerization or temporal polymerization of the polymerizable compound. Examples of the thermal polymerization inhibitor include 4-methoxyphenol, hydroquinone, alkyl or aryl-substituted hydroquinone, t-butylcatechol, pyrogallol, 2-hydroxybenzophenone, 4-methoxy-2-hydroxybenzophenone, cuprous chloride, phenothiazine, Chloranil, naphthylamine, β-naphthol, 2,6-di-tert-butyl-4-cresol, 2,2′-methylenebis (4-methyl-6-tert-butylphenol), pyridine, nitrobenzene, dinitrobenzene, picric acid, 4-Toluidine, methylene blue, copper and organic chelating agent reactant, methyl salicylate, and phenothiazine, nitroso compound, chelate of nitroso compound and Al, and the like.

The photocurable resin composition of the present invention is, for example, adjusted to a viscosity suitable for the coating method with the organic solvent, and on the substrate, dip coating method, flow coating method, roll coating method, bar coater method, screen printing. A tack-free coating film can be formed by applying the organic solvent contained in the composition at a temperature of about 60 to 100 ° C., followed by volatile drying (temporary drying). Moreover, a resin insulation layer can be formed by apply | coating the said composition on a carrier film, and making it dry and winding up as a film together on a base material.

Thereafter, by a contact method (or non-contact method), exposure is selectively performed with an active energy ray through a photomask having a pattern formed thereon or direct pattern exposure is performed by a laser direct exposure machine, and an unexposed portion is diluted with a dilute alkaline aqueous solution (eg, 0.3 A resist pattern is formed by development with a 3 wt% sodium carbonate aqueous solution). Further, for example, by heating to a temperature of about 140 to 180 ° C. and thermosetting, the thermosetting having a carboxyl group of the carboxyl group-containing resin and two or more cyclic ether groups and / or cyclic thioether groups in the molecule. The reactive component reacts to form a cured coating film excellent in various properties such as heat resistance, chemical resistance, moisture absorption resistance, adhesion, and electrical characteristics.

Examples of the base material include printed circuit boards and flexible printed circuit boards that are pre-formed with a circuit, paper-phenol resin, paper-epoxy resin, glass cloth-epoxy resin, glass-polyimide, glass cloth / non-woven cloth-epoxy resin. , Glass cloth / paper-epoxy resin, synthetic fiber-epoxy resin, copper-clad laminates of all grades (FR-4 etc.) using polyimide, polyethylene, PPO, cyanate ester, etc., polyimide film, PET A film, a glass substrate, a ceramic substrate, a wafer plate, or the like can be used.

Volatile drying performed after applying the photocurable resin composition of the present invention is performed in a dryer using a hot air circulation drying furnace, an IR furnace, a hot plate, a convection oven or the like (equipped with an air heating heat source using steam). Can be performed using a method in which the hot air is brought into countercurrent contact and a method in which the hot air is blown onto the support from the nozzle.

After applying the photocurable resin composition of the present invention and evaporating and drying as follows, the resulting coating film is exposed (irradiated with active energy rays). In the coating film, the exposed portion (the portion irradiated by the active energy ray) is cured.

As the exposure apparatus used for the active energy ray irradiation, a direct drawing apparatus (for example, a laser direct imaging apparatus that directly draws an image with a laser using CAD data from a computer), an exposure apparatus equipped with a metal halide lamp, and an (ultra) high pressure mercury lamp. , An exposure machine equipped with a mercury short arc lamp, or a direct drawing apparatus using an ultraviolet lamp such as a (super) high pressure mercury lamp. As the active energy ray, either a gas laser or a solid laser may be used as long as laser light having a maximum wavelength in the range of 350 to 410 nm is used. The exposure amount varies depending on the film thickness and the like, but can be generally in the range of 5 to 200 mJ / cm ² , preferably 5 to 100 mJ / cm ² , more preferably 5 to 50 mJ / cm ² . As the direct drawing apparatus, for example, those manufactured by Nippon Orbotech, Pentax, etc. can be used, and any apparatus may be used as long as it oscillates laser light having a maximum wavelength of 350 to 410 nm. .

The developing method can be a dipping method, a shower method, a spray method, a brush method or the like, and as a developer, potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, Alkaline aqueous solutions such as ammonia and amines can be used.

The photo-curable resin composition of the present invention is in the form of a dry film having a solder resist layer formed by applying and drying a solder resist in advance on a film of polyethylene terephthalate or the like in addition to the method of directly applying the liquid curable resin composition to a substrate. Can also be used. The case where the photocurable resin composition of this invention is used as a dry film is shown below.

The dry film has a structure in which a carrier film, a solder resist layer, and a peelable cover film used as necessary are laminated in this order. The solder resist layer is a layer obtained by applying and drying an alkali-developable photocurable resin composition on a carrier film or a cover film. After forming a solder resist layer on the carrier film, a cover film is laminated thereon, or a solder resist layer is formed on the cover film, and this laminate is laminated on the carrier film to obtain a dry film.

As the carrier film, a thermoplastic film such as a polyester film having a thickness of 2 to 150 μm is used.

The solder resist layer is formed by uniformly applying an alkali-developable photocurable resin composition to a carrier film or cover film with a thickness of 10 to 150 μm using a blade coater, lip coater, comma coater, film coater, etc., and then drying. Is done.

As the cover film, a polyethylene film, a polypropylene film or the like can be used, but it is preferable that the adhesive force with the solder resist layer is smaller than that of the carrier film.

To produce a protective film (permanent protective film) on a printed wiring board using a dry film, peel off the cover film, layer the solder resist layer and the substrate on which the circuit is formed, and bond them together using a laminator, etc. A solder resist layer is formed on the formed substrate. If the formed solder resist layer is exposed, developed, and heat cured in the same manner as described above, a cured coating film can be formed. The carrier film may be peeled off either before exposure or after exposure.

Hereinafter, the present invention will be described in detail with reference to examples and comparative examples. However, the present invention is not limited to the following examples. In the following description, “parts” and “%” are based on mass unless otherwise specified.

Photosensitive resin synthesis example 1:
In an autoclave equipped with a thermometer, a nitrogen introduction device / alkylene oxide introduction device and a stirring device, 106 parts of a novolac type phenol resin (manufactured by Showa Polymer Co., Ltd., hydroxyl equivalent 106), 2.6 parts of a 50% aqueous sodium hydroxide solution, Charge 100 parts of toluene / methyl isobutyl ketone (mass ratio = 2/1), purge the system with nitrogen while stirring, then heat to heat, gradually add 60 parts of propylene oxide at 150 ° C. and 8 kg / cm ^2. Introduced and reacted. The reaction was continued for about 4 hours until the gauge pressure reached 0.0 kg / cm ^2, and then cooled to room temperature. To this reaction solution, 3.3 parts of 36% aqueous hydrochloric acid was added and mixed to neutralize sodium hydroxide. This neutralized reaction product was diluted with toluene, washed with water three times, and desolvated with an evaporator, so that the hydroxyl group equivalent was 164 g / eq. Thus, an alkylene oxide adduct of a novolac type phenol resin was obtained. This was an average of 1 mole of alkylene oxide added per equivalent of hydroxyl group.

164 parts of the alkylene oxide adduct of the resulting novolak type phenol resin, 86 parts of methacrylic acid, 3.0 parts of p-toluenesulfonic acid, 0.05 part of hydroquinone monomethyl ether, and 100 parts of toluene were stirred, a thermometer, and air blown The reactor was equipped with a tube, stirred while blowing air, and reacted at 110 ° C. for 6 hours. After the water produced by the reaction began to distill as an azeotrope with toluene, the reaction was continued for an additional 5 hours and cooled to room temperature. The obtained reaction solution was washed with 5% NaCl aqueous solution, toluene was distilled off with an evaporator, and carbitol acetate was added to obtain a novolak-type PO-added methacrylate resin solution having a nonvolatile content of 70% (double Bond equivalent 250 g / eq. Acid value 0). This is called A-1 varnish.

Photosensitive resin synthesis example 2:
164 parts of an alkylene oxide adduct of the novolak type phenol resin obtained in Synthesis Example 1, 72 parts of acrylic acid, 3.0 parts of p-toluenesulfonic acid, 0.05 part of hydroquinone monomethyl ether, and 100 parts of toluene were stirred and heated. The reactor was equipped with a total and an air blowing tube, stirred while blowing air, and reacted at 90 ° C. for 12 hours. After the water produced by the reaction began to distill as an azeotrope with toluene, the reaction was continued for an additional 5 hours and cooled to room temperature. The obtained reaction solution was washed with 5% NaCl aqueous solution, toluene was distilled off with an evaporator, and carbitol acetate was added to obtain a novolac-type PO-added acrylate resin solution having a nonvolatile content of 70% (double Bond equivalent 236 g / eq.acid value 0). This is called A-2 varnish.

Photosensitive resin synthesis example 3:
In an autoclave equipped with a thermometer, a nitrogen introduction device / alkylene oxide introduction device and a stirring device, 106 parts of a novolac type phenol resin (manufactured by Showa Polymer Co., Ltd., hydroxyl equivalent 106), 2.6 parts of a 50% aqueous sodium hydroxide solution, Charge 100 parts of toluene / methylisobutylketone (mass ratio = 2/1), purge the system with nitrogen while stirring, then heat to increase temperature, and gradually introduce 50 parts of ethylene oxide at 150 ° C. and 8 kg / cm ^2. And reacted. The reaction was continued for about 4 hours until the gauge pressure reached 0.0 kg / cm ^2, and then cooled to room temperature. To this reaction solution, 3.3 parts of 36% aqueous hydrochloric acid was added and mixed to neutralize sodium hydroxide. This neutralization reaction product was diluted with toluene, washed with water three times, and desolvated with an evaporator to obtain an alkylene oxide adduct of a novolak type phenol resin having a hydroxyl group equivalent of 150 g / eq. This was an average of 1 mole of alkylene oxide added per equivalent of hydroxyl group.
150 parts of the novolak-type phenol resin alkylene oxide adduct, 86 parts of methacrylic acid, 3.0 parts of p-toluenesulfonic acid, 0.05 part of hydroquinone monomethyl ether and 100 parts of toluene were stirred, a thermometer, and air blown. The reactor was equipped with a tube, stirred while blowing air, and reacted at 110 ° C. for 6 hours. After the water produced by the reaction began to distill as an azeotrope with toluene, the reaction was continued for an additional 5 hours and cooled to room temperature. The obtained reaction solution was washed with 5% NaCl aqueous solution, toluene was distilled off with an evaporator, and carbitol acetate was added to obtain a novolak EO-added methacrylate resin solution having a nonvolatile content of 70% (double Bond equivalent 236 g / eq.acid value 0). This is called A-3 varnish.

Comparative synthesis example 1:
In an autoclave equipped with a thermometer, a nitrogen introduction device / alkylene oxide introduction device and a stirring device, 94 parts of a monofunctional phenol compound (hydroxyl equivalent 94), 2.6 parts of 50% aqueous sodium hydroxide, toluene / methyl isobutyl ketone (mass) (Ratio = 2/1) 100 parts were charged, and the system was purged with nitrogen while stirring. Next, the temperature was raised by heating, and 50 parts of ethylene oxide was gradually introduced at 150 ° C. and 8 kg / cm ² to react. The reaction was continued for about 4 hours until the gauge pressure reached 0.0 kg / cm ^2, and then cooled to room temperature. To this reaction solution, 3.3 parts of 36% aqueous hydrochloric acid was added and mixed to neutralize sodium hydroxide. This neutralization reaction product was diluted with toluene, washed with water three times, and then the solvent was removed by an evaporator to obtain an alkylene oxide adduct of a phenol compound having a hydroxyl group equivalent of 138 g / eq. This was an average of 1 mole of alkylene oxide added per equivalent of hydroxyl group.
138 parts of an alkylene oxide adduct of the obtained phenol compound, 86 parts of methacrylic acid, 3.0 parts of p-toluenesulfonic acid, 0.05 part of hydroquinone monomethyl ether and 100 parts of toluene were mixed with a stirrer, thermometer and air blowing tube. The reactor was prepared, stirred while blowing air, and reacted at 110 ° C. for 6 hours. After the water produced by the reaction began to distill as an azeotrope with toluene, the reaction was continued for an additional 5 hours and cooled to room temperature. The obtained reaction solution was washed with 5% NaCl aqueous solution, toluene was distilled off with an evaporator, and carbitol acetate was added to obtain an EO-added methacrylate resin solution having a nonvolatile content of 70% (double bond equivalent). 224 g / eq · acid value 0). This is called A-4 varnish.

Example of synthesis of carboxyl group-containing resin (B-1):
Into a 2 liter separable flask equipped with a stirrer, thermometer, reflux condenser, dropping funnel and nitrogen inlet tube, a cresol novolac type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., EOCN-104S, softening point 92 ° C., epoxy) Equivalent 220) 660 g, carbitol acetate 421.3 g, and solvent naphtha 180.6 g were introduced, heated and stirred at 90 ° C., and dissolved. Next, it is once cooled to 60 ° C., 216 g of acrylic acid, 4.0 g of triphenylphosphine and 1.3 g of methylhydroquinone are added and reacted at 100 ° C. for 12 hours, and a reaction product having an acid value of 0.2 mgKOH / g. Got. This was charged with 241.7 g of tetrahydrophthalic anhydride, heated to 90 ° C. and reacted for 6 hours. As a result, a solution of a carboxyl group-containing resin having an acid value of 50 mg KOH / g, a double bond equivalent (g weight of resin per mole of unsaturated groups) of 400, and a weight average molecular weight of 7,000 was obtained. Hereinafter, this carboxyl group-containing resin solution is referred to as B-1 varnish.

Example of synthesis of carboxyl group-containing resin (B-3):
A novolac-type cresol resin (manufactured by Showa Polymer Co., Ltd., trade name “Shonol CRG951”, OH equivalent: 119.4) 119. 4 g, 1.19 g of potassium hydroxide and 119.4 g of toluene were charged, the inside of the system was replaced with nitrogen while stirring, and the temperature was raised by heating. Next, 63.8 g of propylene oxide was gradually dropped and reacted at 125 to 132 ° C. and 0 to 4.8 kg / cm ² for 16 hours. Thereafter, the reaction solution was cooled to room temperature, and 1.56 g of 89% phosphoric acid was added to the reaction solution to neutralize potassium hydroxide, and the novolac type having a nonvolatile content of 62.1% and a hydroxyl value of 182.2 g / eq. A propylene oxide reaction solution of cresol resin was obtained. This was an average of 1.08 moles of alkylene oxide added per equivalent of phenolic hydroxyl group. 293.0 g of an alkylene oxide reaction solution of the obtained novolak-type cresol resin, 43.2 g of acrylic acid, 11.53 g of methanesulfonic acid, 0.18 g of methylhydroquinone and 252.9 g of toluene were mixed with a stirrer, a thermometer and an air blowing tube. The reaction vessel was charged with air at a rate of 10 ml / min and reacted at 110 ° C. for 12 hours while stirring. As the water produced by the reaction, 12.6 g of water was distilled as an azeotrope with toluene. Thereafter, the mixture was cooled to room temperature, and the resulting reaction solution was neutralized with 35.35 g of a 15% aqueous sodium hydroxide solution and then washed with water. Thereafter, toluene was distilled off while substituting 118.1 g of diethylene glycol monoethyl ether acetate with an evaporator to obtain a novolak acrylate resin solution. Next, 332.5 g of the obtained novolac acrylate resin solution and 1.22 g of triphenylphosphine were charged into a reactor equipped with a stirrer, a thermometer and an air blowing tube, and air was blown at a rate of 10 ml / min. While stirring, 60.8 g of tetrahydrophthalic anhydride was gradually added and reacted at 95 to 101 ° C. for 6 hours. A carboxyl group-containing photosensitive resin having a solid acid value of 88 mgKOH / g and a nonvolatile content of 71% was obtained. Hereinafter, this reaction solution is referred to as Varnish B-3.

Examples 1 to 15 and Comparative Examples 1 to 5:
Using the resin solutions of the above synthesis examples, blended in the proportions (parts by mass) shown in Table 1 together with various components shown in Table 1, premixed with a stirrer, kneaded with a three-roll mill, and used for solder resist A photosensitive resin composition was prepared. Here, it was 15 micrometers or less when the dispersion degree of the obtained photosensitive resin composition was evaluated by the particle size measurement by the Grindometer by Eriksen.

Remarks
^{* 1} : NK ester BPE-900 (manufactured by Shin-Nakamura Chemical Co., Ltd.) Bisphenol A skeleton-containing ethylene oxide-modified bifunctional acrylate (double bond equivalent: 556)
^{* 2} : KAYARAD DPCA-60 (manufactured by Nippon Kayaku Co., Ltd.) (double bond equivalent: 210)
^{* 3} : Dipentaerythritol hexaacrylate (DPHA: Nippon Kayaku Co., Ltd.) (double bond equivalent: 108)
^{* 4} : Cyclomer P (ACA) 320 (manufactured by Daicel Chemical Industries, Ltd.)
^{* 5} : ZFR-1124 (Nippon Kayaku Co., Ltd.)
^{* 6} : ZCR-1601H (Nippon Kayaku Co., Ltd.)
^{* 7} : SPV-1000L (Showa Polymer Co., Ltd.)
^{* 8} : 2-Methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one (Irgacure 90 Ciba Specialty Chemicals)
^{* 9} : 2- (Acetyloxyiminomethyl) thiooxanthen-9-one
^{* 10} : Phenol novolac type epoxy resin (DEN438: manufactured by Dow Chemical)
^{* 11} : Bixylenol type epoxy resin (YX-4000: manufactured by Japan Epoxy Resin Co., Ltd.)
^{* 12} : C.I. Pigment Blue 15: 3
^{* 13} : C.I. Pigment Yellow 147
^{* 14} : Barium sulfate (B-30: Sakai Chemical Co., Ltd.)
^{* 15} : Dipropylene glycol monomethyl ether
^{* 16} : Block isocyanate (Asahi Kasei Chemicals)
^{* 17} : Methylated melamine resin (manufactured by Sanwa Chemical Co., Ltd.)
^{* 18} : Antioxidant (Ciba Specialty Chemicals)

Performance evaluation:
<Optimum exposure amount>
The photocurable thermosetting resin compositions of the examples and comparative examples were coated on the entire surface by screen printing after the circuit pattern substrate having a copper thickness of 35 μm was buffed, washed with water, dried, and heated at 80 ° C. Dry in a circulating drying oven for 60 minutes. After drying, exposure is performed through a step tablet (Kodak No. 2) using an exposure apparatus equipped with a high-pressure mercury lamp (short arc lamp), and development (30 ° C., 0.2 MPa, 1 wt% Na ₂ CO ₃ aqueous solution) is performed at 60. When the measurement was performed in seconds, the optimal exposure amount was obtained when the remaining step tablet pattern was 7 steps.
<Dry touch dryness>
Each surface of the photocurable thermosetting resin composition shown in Table 1 was applied onto a patterned copper foil substrate by screen printing, dried in a hot air circulating drying oven at 80 ° C. for 30 minutes, and allowed to cool to room temperature. . A PET film was pressed against this substrate, and then the sticking state of the film when the negative film was peeled off was evaluated.
(Double-circle): When peeling a film, there is no resistance and a trace is not left in a coating film.
○: When the film is peeled off, there is no resistance, but the coating film has a slight mark.
(Triangle | delta): When peeling a film, there exists resistance slightly and the coating film has a trace.
X: When the film is peeled off, there is resistance and the coating film is clearly marked.
<Resolution>
A circuit pattern substrate having a line / space of 300/300 μm and a copper thickness of 35 μm was coated with the photocurable thermosetting resin compositions of Examples and Comparative Examples by buffing, washing with water, drying and then applying by screen printing. , And dried in a hot air circulation drying oven at 80 ° C. for 30 minutes. After drying, exposure was performed using an exposure apparatus equipped with a high-pressure mercury lamp (short arc lamp). As the exposure pattern, a glass dry plate for drawing a 20/30/40/50/60/70/80/90/100 μm line in the space portion was used. The active energy ray was irradiated so that the exposure amount became the optimal exposure amount of the photosensitive resin composition. After the exposure, development was performed with a 1 wt% Na ₂ CO ₃ aqueous solution at 30 ° C. to draw a pattern, and a cured coating film was obtained by heat curing at 150 ° C. for 60 minutes.
It calculated | required using the optical microscope which adjusted the minimum residual line of the cured coating film of the obtained photosensitive resin composition for solder resists 200 times (resolution).
<Tensile modulus, tensile strength (tensile breaking strength), elongation (tensile breaking elongation)>
The composition of each of the above composition examples and comparative composition examples was applied to a PTFE (polytetrafluoroethylene) plate that had been washed and dried in advance by a screen printing method, and dried at 80 ° C. for 30 minutes in a hot-air circulating drying oven. . This was cooled to room temperature, exposed at an appropriate exposure amount, and developed with a 1 wt% Na ₂ CO ₃ aqueous solution at 30 ° C. for 60 seconds under a spray pressure of 2 kg / cm ² . This substrate was irradiated with ultraviolet rays under a condition of an integrated exposure amount of 1000 mJ / cm ^{2 in} a UV conveyor furnace, and then cured at 150 ° C. for 60 minutes in a hot air circulating drying furnace. After cooling this to room temperature, the cured coating film was peeled off from the PTFE plate to obtain an evaluation sample.
The tensile elasticity modulus, tensile strength (tensile fracture strength), and elongation rate (tensile fracture elongation) of the above evaluation samples were measured with a tension-compression tester (manufactured by Shimadzu Corporation).
<Flexibility>
The compositions of the above Examples and Comparative Examples were applied by screen printing to a Kapton material (thickness 25 μm) that had been washed and dried in advance, and dried at 80 ° C. for 30 minutes in a hot air circulating drying furnace. After cooling this to room temperature, it is exposed with an appropriate exposure amount using an exposure apparatus equipped with a high-pressure mercury lamp (short arc lamp), and a 1 wt% Na ₂ CO ₃ aqueous solution at 30 ° C. is applied under a spray pressure of 2 kg / cm ^2. Development was performed for 2 seconds. This substrate was irradiated with ultraviolet rays under a condition of an integrated exposure amount of 1000 mJ / cm ^{2 in} a UV conveyor furnace and then cured by heating at 150 ° C. for 60 minutes to obtain an evaluation sample for a folding resistance test and a flexibility test. .
A method in which one side of a film-shaped test piece prepared by processing the obtained cured film into a width of 10 mm and a length of 90 mm is placed on an electronic balance and the other side is bent until the distance between the films reaches 3 mm. The maximum load applied to the electronic balance was evaluated as the repulsive force according to the following criteria.
○: Less than 10 g Δ: 10 to less than 30 g ×: 30 g or more

Characteristic test:
The composition of each of the above Examples and Comparative Examples was applied on the entire surface of a patterned copper foil substrate so that the film thickness after drying by screen printing was 20 μm, dried at 80 ° C. for 30 minutes, and then released to room temperature. Cool down. The substrate is exposed to a solder resist pattern at an optimum exposure amount using an exposure apparatus equipped with a high-pressure mercury lamp (short arc lamp), and a 1 wt% Na ₂ CO ₃ aqueous solution at 30 ° C. is applied for 60 seconds under a spray pressure of 2 kg / cm ^2. Development was performed to obtain a resist pattern. This substrate was irradiated with ultraviolet rays under a condition of an integrated exposure amount of 1000 mJ / cm ^{2 in} a UV conveyor furnace, and then cured by heating at 150 ° C. for 60 minutes. The characteristics of the obtained printed circuit board (evaluation board) were evaluated as follows.
<Solder heat resistance>
The evaluation board | substrate which apply | coated the rosin-type flux was immersed in the solder tank previously set to 260 degreeC, and after washing | cleaning the flux with denatured alcohol, the swelling / peeling of the resist layer by visual observation was evaluated. The judgment criteria are as follows.
A: Peeling is not observed even after 10 seconds of immersion for 6 or more times.
○: No peeling is observed even if the immersion for 10 seconds is repeated 3 times or more.
(Triangle | delta): It peels for a while when immersion for 10 seconds is repeated 3 times or more.
X: The resist layer swells and peels off within 3 times for 10 seconds.
<Electroless gold plating resistance>
Using commercially available electroless nickel plating bath and electroless gold plating bath, plating is performed under the conditions of nickel 0.5 μm and gold 0.03 μm, and the tape peeling causes the presence or absence of resist layer peeling or plating penetration. After evaluating the presence or absence, the presence or absence of peeling of the resist layer was evaluated by tape peeling. The judgment criteria are as follows.
A: No soaking or peeling is observed.
○: Slight penetration is confirmed after plating, but does not peel off after tape peeling.
Δ: Slight penetration after plating and peeling after tape peel.
X: There is peeling after plating.
<Electrical characteristics>
An evaluation substrate was prepared under the above conditions using a comb-type electrode pattern of line / space = 50/50 μm instead of the copper foil substrate, a bias voltage of DC 10 V was applied to the comb-type electrode, and 130 ° C., 85% R . H. The insulation resistance value after 100 hours was measured in the tank. The measurement voltage was DC 10V.
<Alkali resistance>
The evaluation substrate was immersed in a 10 wt% NaOH aqueous solution at 50 ° C. for 30 minutes, and soaking and dissolution of the coating film were confirmed. Further, peeling by tape beer was confirmed. Judgment criteria are as follows.
○: No soaking, melting or peeling.
Δ: Slight penetration, dissolution or peeling is confirmed.
X: Significant infiltration, dissolution or peeling.
<Dry film production>
After each of the photosensitive resin compositions for solder resists of Example 1 and Comparative Example 1 were appropriately diluted with methyl ethyl ketone, a PET film (Toray FB-50: manufactured by Toray Industries, Inc.) was prepared using an applicator so that the film thickness after drying was 20 μm. 16 μm) and dried at 80 ° C. for 30 minutes to obtain a dry film.
<Board fabrication>
After the circuit-formed substrate is buffed, the dry film produced by the above method is pressurized using a vacuum laminator (MVLP-500, manufactured by Meiki Seisakusho): 0.8 MPa, 70 ° C., 1 minute, degree of vacuum The substrate (unexposed substrate) having an unexposed solder resist layer was obtained by heat lamination under the condition of 133.3 Pa.
The evaluation results are shown in Table 2.

As shown in Table 2 above, in the case of Examples 1 to 15 of the present invention, higher sensitivity was achieved without lowering the dryness to touch compared with Comparative Examples 1 to 5, and the obtained curing was obtained. The film was found to have excellent flexibility. In particular, in Examples using the photosensitive resin A-1 in which propylene oxide and methacrylic acid are added to a novolak-type phenolic resin, it has excellent solder heat resistance, electroless gold plating resistance, electrical characteristics, and alkali developability light. It was found useful as a curable resin composition.
On the other hand, in Comparative Examples 1 and 2 using A-4 and A-5 having 3 or less nuclei, the dryness to touch, the solder heat resistance, and the electrical properties were inferior.

As described above, a photocurable resin composition that is excellent in dryness to touch of a dry coating film, is highly sensitive and flexible, and can form a cured film having high insulation resistance especially when humidified at high temperature, and its dry film and cured product In addition, a printed wiring board in which a cured film such as a solder resist is formed can be provided.

Claims

An alkali-developable photocurable resin composition comprising a photosensitive resin having a structure represented by the following general formula (I), a carboxyl group-containing resin, and a photopolymerization initiator.

(Wherein R 1 is a hydrogen atom or an organic group having 1 to 20 carbon atoms, which may be the same or different,
R 2 represents at least one functional group selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an alkylene group having 1 to 10 carbon atoms, and a phenylene group,
R 3 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms,
R 4 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms,
R 5 represents a hydrogen atom or a methyl group,
p represents an integer of 1 to 5, q represents an integer of 3 or more,
m represents an integer of 1 to 4, and n represents an integer of 1 to 10. )
The photocurable resin composition according to claim 1, wherein the photosensitive resin contains no acid and has a double bond equivalent of 200 or more and 400 or less.
The photosensitive resin is obtained by reacting a compound having three or more phenolic hydroxyl groups in one molecule with a cyclic ether compound or a cyclic carbonate compound, and reacting a compound having an ethylenically unsaturated group with the generated hydroxyl group. The photocurable resin composition according to claim 1, wherein the photocurable resin composition is a photosensitive resin.
The photocurable resin composition according to claim 2, wherein the compound having three or more phenolic hydroxyl groups in one molecule is a compound having a phenolic hydroxyl group having a softening point of room temperature or higher.
The photocurable resin composition according to claim 2, wherein the compound having an ethylenically unsaturated group is methacrylic acid.
Furthermore, it is a photocurable thermosetting resin composition containing a thermosetting component, The photocurable resin composition as described in any one of Claim 1 to 4 characterized by the above-mentioned.
Furthermore, it is a soldering resist containing a coloring agent, The photocurable resin composition as described in any one of Claim 1 to 5 characterized by the above-mentioned.
The photocurable dry film obtained by apply | coating and drying the photocurable resin composition as described in any one of the said Claim 1 to a carrier film.
A cured product obtained by photocuring the photocurable resin composition according to any one of claims 1 to 6 or the dry film according to claim 7 on copper.
A cured product obtained by photocuring the photocurable resin composition according to any one of claims 1 to 6 or the dry film according to claim 7 in a pattern.
A cured film obtained by photocuring the photocurable resin composition according to any one of claims 1 to 6 or the dry film according to claim 7 in a pattern, and then thermosetting. A printed wiring board having: