JP7113644B2 - Dry films, cured products and printed wiring boards - Google Patents

Description

The present invention relates to dry films, cured products and printed wiring boards.

Conventionally, as a method for manufacturing a printed wiring board, an interlayer insulating layer made of a thermosetting resin composition is formed on a substrate on which a circuit is formed, openings for via holes are provided in this interlayer insulating layer with a laser such as carbon dioxide gas, and further A method of forming a conductive circuit including via holes by plating is widely known.
In the manufacturing method of such a printed wiring board, as electronic devices become more sophisticated and smaller and lighter in weight in recent years, the density of conductor circuits also advances, and it is necessary to form openings for via holes with smaller diameters in interlayer insulating layers. was there. However, with conventional carbon dioxide laser processing, it is difficult to form openings with a diameter of 40 μm or less. On the other hand, UV laser processing, which can form smaller diameter openings, is also conceivable. .

On the other hand, a method of applying a photolithographic technique conventionally used for forming a solder resist to forming an opening for a via hole in an interlayer insulating layer is being studied.
For example, as a material for an interlayer insulating layer using a photosensitive resin composition, a binder having an alkali-developable and photocurable functional group, a photopolymerizable monomer, a thermosetting epoxy resin, silica, A photosensitive resin composition containing a photopolymerization initiator and a curing catalyst has been proposed (see Patent Document 1).

However, recent via hole openings are required not only to have a small diameter but also to have a high resolution in which the ratio of the top diameter to the bottom diameter of the opening (bottom diameter/top diameter) is substantially 1. However, the photosensitive resin composition in the above proposal could not sufficiently cope with the problem. Moreover, since the photosensitive resin composition in the above proposal contains a large amount of components such as fillers, residue during development (so-called development residue) is likely to occur at the bottom of the via hole opening, and connection reliability of the conductor circuit at the via hole opening is improved. had a problem.

On the other hand, a copper circuit forming technique called Semi Additive Process (hereinafter simply referred to as "SAP") is attracting attention due to the demand for forming miniaturized conductor circuits in the method of manufacturing printed wiring boards. In such SAP technology, as a method of forming a seed layer (a conductive layer for electrolytic copper plating), copper sputtering treatment or electroless copper plating treatment is performed. Adopted.
However, unlike copper sputtering, it is difficult for electroless copper plating to maintain excellent adhesion to the interlayer insulating layer, so-called peel strength. was desired.

JP 2017-111415 A

Therefore, the object of the present invention is to provide a light source suitable for use in SAP, which has excellent resolution and developability in addition to the reduction in the diameter of the via hole opening, and also has excellent adhesion to finer conductor circuits. An object of the present invention is to provide a dry film comprising a layer of a curable resin composition.

The inventors of the present invention have made intensive studies to achieve the above object. As a result, a support film having a rough surface with an arithmetic mean surface roughness Ra within a specific range and a compound having a molecular weight within a specific range and having the number of photosensitive groups and hydrophilic groups in one molecule controlled within a predetermined range The present inventors have found that the above object can be achieved by using an alkali-developable photocurable resin composition containing a dry film together, and have completed the present invention.

That is, the dry film of the present invention is a dry film comprising a layer of a photocurable resin composition on the rough surface side of a support film having a rough surface having an arithmetic mean surface roughness Ra of 100 to 1000 nm, The photocurable resin composition has (A) a compound having a molecular weight of 500 or less having 0 to 2 (meth)acryloyl groups and at least one carboxyl group in one molecule, (B) an alkali-soluble resin, ( C) a photopolymerization initiator, and (D) a thermosetting compound.

In addition, it is preferable that the support film has an arithmetic mean surface roughness Ra of 300 nm or less on the opposite side that does not come into contact with the layer of the photocurable resin composition.

Further, the dry film of the present invention preferably has a light transmittance of 90% or less at a wavelength of 365 nm of the dry film comprising a layer of a support film and a photocurable resin composition.

Further, the cured product of the present invention is characterized by being obtained by curing the layer of the photocurable resin composition included in the dry film.

Furthermore, the printed wiring board of the present invention is characterized by having the cured product.

According to the present invention, in addition to the diameter reduction of the via hole opening, it has excellent resolution and excellent developability that can satisfy electrical connection reliability at the bottom of the via hole opening, and has a finer conductor circuit. It is possible to provide a dry film having a layer of a photocurable resin composition suitable for use in SAP, which is also excellent in adhesion to.

Embodiments of the present invention will be described in detail below.

First, the layer of the photocurable resin composition (sometimes simply referred to as "resin layer") that constitutes the dry film of the present invention will be described.
In order to achieve the object of the present invention, the layer of this photocurable resin composition has (A) a molecular weight of 500 having 0 to 2 (meth)acryloyl groups and at least one carboxyl group in one molecule. It is necessary to contain the following compounds, (B) an alkali-soluble resin, (C) a photopolymerization initiator, and (D) a thermosetting compound. Here, the (meth)acryloyl group is a generic term for acryloyl groups, methacryloyl groups and mixtures thereof.

[(A) a compound having 0 to 2 (meth)acryloyl groups and at least one carboxyl group in one molecule and having a molecular weight of 500 or less (hereinafter abbreviated as "compound X")]
By blending the compound X having at least one carboxyl group and having a molecular weight of 500 or less, the solubility of the unexposed area in the developing solution in the developing process is improved, and the generation of development residue at the bottom of the via hole opening is suppressed. be able to. Moreover, when the carboxyl group contributes to the reaction with a thermosetting component such as an epoxy resin, it is believed that it also contributes to the improvement of the peel strength.
On the other hand, when the compound X has a (meth)acryloyl group, in addition to the improvement of developability due to the carboxyl group, the resistance to development of the exposed area is improved, and the exposed area and the unexposed area dissolve in the developer. Since the contrast becomes clearer, excellent resolution can be exhibited even by further reducing the diameter of the via hole opening.
In addition, the number of (meth)acryloyl groups is set to 2 or less in order to avoid deterioration of the dimensional accuracy of the bottom of the via hole opening due to halation (light reflection) caused by the copper circuit.

As such compound X, compounds having 0 to 2 (meth)acryloyl groups and at least 1, preferably 1 carboxyl group in one molecule and having a molecular weight of 500 or less are known. Commonly used ones can be used, and may have other functional groups such as phenolic hydroxyl groups, alcoholic hydroxyl groups, thiol groups, sulfonyl groups, amino groups and isocyanate groups.
In addition, it is preferable that this compound X has a high solubility in an alkaline aqueous solution as much as possible.

This compound X can be used individually by 1 type or in combination of 2 or more types.
The content of this compound X is preferably 1 to 20 parts by mass in terms of non-volatile components with respect to 100 parts by mass of the (B) alkali-soluble resin. Within the above range, the effect of suppressing development residues and the dissolution contrast between the exposed and unexposed areas in the developer are improved, which is preferable.

[(B) Alkali-soluble resin]
The photocurable resin composition constituting the dry film of the present invention contains (B) an alkali-soluble resin. As the alkali-soluble resin, any resin that contains at least one functional group selected from a phenolic hydroxyl group, a thiol group, a sulfonyl group and a carboxyl group and is soluble in an alkaline solution can be used, preferably. A compound having two or more phenolic hydroxyl groups, a carboxyl group-containing resin, a compound having a phenolic hydroxyl group and a carboxyl group, a compound having two or more thiol groups, and a compound having a sulfo group can be used. In particular, as the alkali-soluble resin, a carboxyl group-containing resin is more preferable.
From the viewpoint of photocurability and development resistance, the carboxyl group-containing resin preferably has an ethylenically unsaturated group in the molecule in addition to the carboxyl group. A (meth)acryloyl group is preferred as the ethylenically unsaturated group.

Carboxyl group-containing resins include, for example, compounds (both oligomers and polymers) listed below.

(1) A carboxyl group-containing resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth)acrylic acid and an unsaturated group-containing compound such as styrene, α-methylstyrene, lower alkyl (meth)acrylate, isobutylene, or the like.

(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-based polyols, and polyether-based Carboxyl group-containing urethane resins obtained by polyaddition reaction of diol compounds such as polyols, polyester-based polyols, polyolefin-based polyols, acrylic polyols, bisphenol A-based alkylene oxide adduct diols, and compounds having phenolic hydroxyl groups and alcoholic hydroxyl groups.

(3) Diisocyanate compounds such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, and aromatic diisocyanates, polycarbonate-based polyols, polyether-based polyols, polyester-based polyols, polyolefin-based polyols, acrylic polyols, and bisphenol A-based A terminal carboxyl group-containing urethane resin obtained by reacting an acid anhydride with the terminal of a urethane resin obtained by a polyaddition reaction of a diol compound such as an alkylene oxide adduct diol, a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

(4) 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 obtained by a polyaddition reaction of meth)acrylate or its partial acid anhydride modified product, a carboxyl group-containing dialcohol compound and a diol compound.

(5) During the synthesis of the resin of (2) or (4) above, a compound having one hydroxyl group and one or more (meth)acryloyl groups in the molecule such as hydroxyalkyl (meth)acrylate is added, and the terminal ( Meta) acrylated urethane resin containing carboxyl groups.

(6) During the synthesis of the resin of (2) or (4), one isocyanate group and one or more (meth)acryloyl groups in the molecule, such as an equimolar reaction product of isophorone diisocyanate and pentaerythritol triacrylate A carboxyl group-containing urethane resin that is terminally (meth)acrylated by adding a compound having

(7) Photosensitivity obtained by reacting a polyfunctional epoxy resin with (meth)acrylic acid and adding a dibasic acid anhydride such as phthalic anhydride, tetrahydrophthalic anhydride, or hexahydrophthalic anhydride to the hydroxyl group present in the side chain. Carboxyl group-containing resin.

(8) A photosensitive carboxyl group obtained by reacting (meth)acrylic acid with a polyfunctional epoxy resin obtained by further epoxidizing the hydroxyl group of a bifunctional epoxy resin with epichlorohydrin, and adding a dibasic acid anhydride to the resulting hydroxyl group. Contained resin.

(9) A carboxyl group-containing polyester resin obtained by reacting a polyfunctional oxetane resin with a dicarboxylic acid and adding a dibasic acid anhydride to the resulting primary hydroxyl group.

(10) A reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide and reacting an unsaturated group-containing monocarboxylic acid to obtain a reaction product A carboxyl group-containing photosensitive resin obtained by reacting a polybasic acid anhydride with a substance.

(11) Obtained by reacting a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate with a monocarboxylic acid containing an unsaturated group. A carboxyl group-containing photosensitive resin obtained by reacting a reaction product with a polybasic acid anhydride.

(12) an epoxy compound having a plurality of epoxy groups in one molecule, a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule such as p-hydroxyphenethyl alcohol; Maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipic acid to the alcoholic hydroxyl group of the reaction product obtained by reacting with a monocarboxylic acid containing an unsaturated group such as acrylic acid. A carboxyl group-containing photosensitive resin obtained by reacting a polybasic acid anhydride such as an acid.

(13) One epoxy group and one or more (meth)acryloyl in the molecule of glycidyl (meth)acrylate, α-methylglycidyl (meth)acrylate, or the like in any one of the resins (1) to (12) above. A photosensitive carboxyl group-containing resin obtained by adding a compound having a group.

(14) A photosensitive carboxyl group-containing resin obtained by reacting a carboxyl group-containing (meth)acrylic copolymer resin with a compound having an oxirane ring and an ethylenically unsaturated group in one molecule.

(15) A compound having one epoxy group and an unsaturated double bond in each molecule and a copolymer of a compound having an unsaturated double bond are reacted with an unsaturated monocarboxylic acid to produce the second A photosensitive carboxyl group-containing resin obtained by reacting a secondary hydroxyl group with a saturated or unsaturated polybasic acid anhydride.

(16) After reacting a hydroxyl group-containing polymer with a saturated or unsaturated polybasic acid anhydride, the resulting carboxylic acid is reacted with a compound having one epoxy group and an unsaturated double bond in each molecule. a photosensitive hydroxyl group- and carboxyl group-containing resin obtained by

Since the carboxyl group-containing resin as described above has a large number of carboxyl groups in the side chains of the backbone polymer, development with an alkaline aqueous solution is possible.

Also, as the alkali-soluble resin, an alkali-soluble resin having at least one amideimide structure represented by the following formula (a) or (b) can be preferably used. By containing a resin having an imide bond directly bonded to a cyclohexane ring or a benzene ring, a cured product having more excellent toughness and heat resistance can be obtained. In particular, an amideimide resin having a structure represented by the following (a) is excellent in light transmittance, and thus can further improve the resolution of the resin composition. The alkali-soluble resin having at least one of the amideimide structures represented by the following formula (a) or (b) preferably has transparency. % or more.

The content of the structures represented by formulas (a) and (b) in the alkali-soluble resin having the amide-imide structure is preferably 10 to 70% by mass. By using such a resin, it is possible to obtain a cured product that is excellent in solvent solubility, heat resistance, physical properties such as tensile strength and elongation, and dimensional stability. It is preferably 10 to 60% by mass, more preferably 20 to 50% by mass.

（式（ａ１）および（ａ２）中、それぞれ、Ｒは１価の有機基であり、Ｈ、ＣＦ_３またはＣＨ_３であることが好ましく、Ｘは直接結合または２価の有機基であり、直接結合、ＣＨ_２またはＣ（ＣＨ_３）_２等のアルキレン基であることが好ましい。）で表される構造を有する樹脂が、引張強度や伸度等の物性および寸法安定性に優れるため好ましい。溶解性や機械物性の観点から、式（ａ）の構造を有するアミドイミド樹脂として、式（ａ１）および（ａ２）の構造を１０～１００質量％有する樹脂を好適に用いることができる。より好ましくは２０～８０質量％である。 As the alkali-soluble resin having an amide imide structure represented by formula (a), in particular, the following formula (a1) or (a2)

(in formulas (a1) and (a2), respectively, R is a monovalent organic group, preferably H, _CF3 or _CH3 ; X is a direct bond or a divalent organic group; and It is preferably a bond, or an alkylene group such as CH ₂ or C(CH ₃ ) ₂ .) is preferable because it has excellent physical properties such as tensile strength and elongation, and dimensional stability. From the viewpoint of solubility and mechanical properties, resins having 10 to 100 mass % of the structures of formulas (a1) and (a2) can be preferably used as the amideimide resin having the structure of formula (a). More preferably, it is 20 to 80% by mass.

Further, as the amideimide resin having the structure of the formula (a), an amideimide resin containing 5 to 100 mol% of the structures of the formulas (a1) and (a2) can be preferably used from the viewpoint of solubility and mechanical properties. . It is more preferably 5 to 98 mol %, still more preferably 10 to 98 mol %, particularly preferably 20 to 80 mol %.

（式（ｂ１）および（ｂ２）中、それぞれ、Ｒは１価の有機基であり、Ｈ、ＣＦ_３またはＣＨ_３であることが好ましく、Ｘは直接結合または２価の有機基であり、直接結合、ＣＨ_２またはＣ（ＣＨ_３）_２などのアルキレン基であることが好ましい。）で表される構造を有する樹脂が、引張強度や伸度等の機械的物性に優れる硬化物が得られることから好ましい。溶解性や機械物性の観点から、式（ｂ）の構造を有するアミドイミド樹脂として、式（ｂ１）および（ｂ２）の構造を１０～１００質量％有する樹脂を好適に用いることができる。より好ましくは２０～８０質量％である。 Further, as the alkali-soluble resin having an amide imide structure represented by formula (b), in particular, formula (b1) or (b2)

(in formulas (b1) and (b2), respectively, R is a monovalent organic group, preferably H, _CF3 or _CH3 ; X is a direct bond or a divalent organic group; and A bond, an alkylene group such as CH ₂ or C(CH ₃ ) ₂ is preferable.) A cured product having excellent mechanical properties such as tensile strength and elongation can be obtained. preferred from From the viewpoint of solubility and mechanical properties, resins having 10 to 100% by mass of the structures of formulas (b1) and (b2) can be suitably used as the amideimide resin having the structure of formula (b). More preferably, it is 20 to 80% by mass.

As the amideimide resin having the structure of formula (b), an amideimide resin containing 2 to 95 mol% of the structures of formulas (b1) and (b2) can also be preferably used for the reason of exhibiting good mechanical properties. More preferably 10 to 80 mol %.

An alkali-soluble resin having an amide-imide structure can be obtained by a known method. The amideimide resin having the structure of formula (a) can be obtained, for example, using a diisocyanate compound having a biphenyl skeleton and cyclohexanepolycarboxylic acid anhydride.

Diisocyanate compounds having a biphenyl skeleton include 4,4'-diisocyanate-3,3'-dimethyl-1,1'-biphenyl, 4,4'-diisocyanate-3,3'-diethyl-1,1'-biphenyl , 4,4′-diisocyanate-2,2′-dimethyl-1,1′-biphenyl, 4,4′-diisocyanate-2,2′-diethyl-1,1′-biphenyl, 4,4′-diisocyanate- 3,3'-ditrifluoromethyl-1,1'-biphenyl, 4,4'-diisocyanate-2,2'-ditrifluoromethyl-1,1'-biphenyl and the like. In addition, aromatic polyisocyanate compounds such as diphenylmethane diisocyanate may be used.

Cyclohexanepolycarboxylic anhydrides include cyclohexanetricarboxylic anhydride and cyclohexanetetracarboxylic anhydride.

Also, the amideimide resin having the structure of formula (b) can be obtained, for example, using the diisocyanate compound having the biphenyl skeleton and the polycarboxylic acid hydrate having two acid anhydride groups.

Examples of polycarboxylic acid waters having two acid anhydride groups include pyromellitic dianhydride, benzophenone-3,3′,4,4′-tetracarboxylic dianhydride, diphenyl ether-3,3′, 4,4'-tetracarboxylic dianhydride, benzene-1,2,3,4-tetracarboxylic dianhydride, biphenyl-3,3',4,4'-tetracarboxylic dianhydride, biphenyl- 2,2′,3,3′-tetracarboxylic dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, 1,1 -bis(2,3-dicarboxyphenyl)ethane dianhydride, 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 2,3-bis(3,4-dicarboxyphenyl)propane dianhydride, bis(3,4-dicarboxyphenyl)sulfone dianhydride, bis(3,4-dicarboxyphenyl)ether di Anhydrides, alkylene glycol bis-anhydrotrimellitate such as ethylene glycol bis-anhydro-trimellitate, and the like.

Specific examples of the alkali-soluble resin having the amide imide structure include Unidic V-8000 series manufactured by DIC Corporation and SOXR-U manufactured by Nippon Kodoshi Co., Ltd.

The (B) alkali-soluble resin as described above may be used singly or in combination of two or more.
Such an alkali-soluble resin preferably has an acid value in the range of 20-120 mgKOH/g, more preferably in the range of 30-100 mgKOH/g. By setting the acid value of the alkali-soluble resin within the above range, good alkali development becomes possible, and a normal cured product pattern can be formed.
The weight-average molecular weight of such an alkali-soluble resin varies depending on the resin skeleton, but is generally preferably from 2,000 to 150,000. When the weight-average molecular weight is 2,000 or more, the tack-free properties of the dried coating film and the moisture resistance of the coating film after exposure are good, and the resolution is also better. On the other hand, when the weight average molecular weight is 150,000 or less, the developability and storage stability are good. More preferably 2,000 to 50,000.

(Compound having an ethylenically unsaturated group)
The photocurable resin composition constituting the dry film of the present invention can contain a compound having an ethylenically unsaturated group in addition to the components (A) and (B). In the present specification, when other components including components (A) and (B) have an ethylenically unsaturated group, such components are excluded from the "compound having an ethylenically unsaturated group". do.

As the compound having an ethylenically unsaturated group, a known and commonly used photopolymerizable oligomer, photopolymerizable vinyl monomer, or the like can be used.
Examples of photopolymerizable oligomers include unsaturated polyester-based oligomers and (meth)acrylate-based oligomers. (Meth)acrylate oligomers include epoxy (meth)acrylates such as phenol novolac epoxy (meth)acrylate, cresol novolac epoxy (meth)acrylate, bisphenol type epoxy (meth)acrylate, urethane (meth)acrylate, epoxyurethane (meth)acrylate, ) acrylates, polyester (meth)acrylates, polyether (meth)acrylates, polybutadiene-modified (meth)acrylates, and the like.

Examples of photopolymerizable vinyl monomers include styrene derivatives such as styrene, chlorostyrene and α-methylstyrene; vinyl esters such as vinyl acetate, vinyl butyrate and vinyl benzoate; vinyl isobutyl ether, vinyl-n-butyl ether, vinyl -Vinyl ethers such as t-butyl ether, vinyl-n-amyl ether, vinyl isoamyl ether, vinyl-n-octadecyl ether, vinylcyclohexyl ether, ethylene glycol monobutyl vinyl ether, triethylene glycol monomethyl vinyl ether; acrylamide, methacrylamide, N- (Meth)acrylamides such as hydroxymethylacrylamide, N-hydroxymethylmethacrylamide, N-methoxymethylacrylamide, N-ethoxymethylacrylamide, and N-butoxymethylacrylamide; triallyl isocyanurate, diallyl phthalate, diallyl isophthalate, etc. Allyl compounds; (meth)acryl such as 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, phenyl (meth)acrylate, phenoxyethyl (meth)acrylate acid esters; hydroxyalkyl (meth)acrylates such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and pentaerythritol tri(meth)acrylate; methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, etc. Alkoxyalkylene glycol mono (meth) acrylates; ethylene glycol di (meth) acrylate, butanediol di (meth) acrylates, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, tri Alkylene polyol poly(meth)acrylates such as methylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate; diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, Polyoxyalkylene glycol poly(meth)acrylates such as ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane tri(meth)acrylate, etc. poly(meth)acrylates such as hydroxypivalic acid neopentylglycol ester di(meth)acrylate; and isocyanurate type poly(meth)acrylates such as tris[(meth)acryloxyethyl]isocyanurate.

Such a compound having an ethylenically unsaturated group is preferably a compound having a (meth)acryloyl group, that is, a (meth)acrylate compound. In addition, the (meth)acrylate compound is preferably bifunctional or higher because it has better heat resistance. Further, when the acrylic equivalent of the (meth)acrylate compound is 100 or more, the elongation rate becomes better, the halation is further suppressed, and the cured product is less likely to warp, which is preferable.

式中、Ｒ^１は水素原子、炭素数１～２０の有機基であり、同一でも異なっていてもよく、
Ｒ^２は、炭素数１～１０のアルキル基、炭素数１～１０のアルキレン基、およびフェニレン基よりなる群から選ばれる少なくとも１種の官能基を表し、
Ｒ^３は、水素原子または炭素数１～４のアルキル基を表し、
Ｒ^４は水素原子または炭素数１～４のアルキル基を表し、
Ｒ^５は水素原子またはメチル基を表し、
ｐは１～５の整数を表し、ｑは、３以上の整数を表し、
ｍは１～４の整数を表し、ｎは１～１０の整数を表わす。
好適な態様においては、下記一般式（ｉ）で表される（メタ）アクリレート化合物は、１分子中に３つ以上のフェノール性水酸基を有する化合物に、環状エーテル化合物または環状カーボネート化合物を反応させ、生成した水酸基にエチレン性不飽和基を有する化合物を反応させて得られるアクリレート化合物である。 この場合、好ましくは、上記１分子中に３つ以上のフェノール性水酸基を有する化合物は、室温以上の軟化点をもつフェノール性水酸基を有する化合物であり、また、上記エチレン性不飽和基を有する化合物は、メタクリル酸であることが好ましい。 In particular, as the compound having an ethylenically unsaturated group, a (meth)acrylate compound represented by the following general formula (i) is more preferable because insulation reliability is improved.

In the formula, R ¹ is a hydrogen atom, 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,
^R5 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 1-4; n represents an integer of 1-10;
In a preferred embodiment, the (meth)acrylate compound represented by the following general formula (i) 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, It is an acrylate compound obtained by reacting the produced hydroxyl group with a compound having an ethylenically unsaturated group. 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 an ethylenically unsaturated group. is preferably methacrylic acid.

Such a compound having an ethylenically unsaturated group may be used alone or in combination of two or more.
The amount of the compound having an ethylenically unsaturated group is 1 to 80 parts by mass, preferably 2 to 70 parts by mass, per 100 parts by mass of the alkali-soluble resin (B).

[(C) Photoinitiator]
As the photopolymerization initiator, any known and commonly used photopolymerization initiator can be used.

Examples of photopolymerization initiators include bis-(2,6-dichlorobenzoyl)phenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis-(2, 6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis-(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis-( 2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide, bis-(2,4,6- bisacylphosphine oxides such as trimethylbenzoyl)-phenylphosphine oxide (manufactured by BASF Japan, IRGACURE819); 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4 ,6-trimethylbenzoylphenylphosphine acid methyl ester, 2-methylbenzoyldiphenylphosphine oxide, pivaloylphenylphosphinic acid isopropyl ester, 2,4,6-trimethylbenzoyldiphenylphosphine oxide (manufactured by BASF Japan, DAROCUR TPO) and other monoacylphosphine oxides; 1-hydroxy-cyclohexylphenyl ketone, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one, 2-hydroxy-2-methyl-1-phenyl Hydroxyacetophenones such as propan-1-one; benzoins such as benzoin, benzyl, benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, benzoin n-butyl ether; benzoin alkyl ethers; benzophenone, p - benzophenones such as methylbenzophenone, Michler's ketone, methylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bisdiethylaminobenzophenone; Toxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenylketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino -1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 (manufactured by BASF Japan, IRGACURE369), 2-(dimethylamino)-2-[(4-methyl Acetophenones such as phenyl)methyl)-1-[4-(4-morpholinyl)phenyl]-1-butanone and N,N-dimethylaminoacetophenone; thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2,4- Thioxanthones such as dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone; anthraquinone, chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, Anthraquinones such as chloroanthraquinone, 2-amyl anthraquinone, and 2-aminoanthraquinone; Ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; Ethyl-4-dimethylaminobenzoate, 2-(dimethylamino)ethylbenzoate, p-dimethylbenzoate Benzoic acid esters such as acid ethyl ester; 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzoyloxime)], ethanone, 1-[9-ethyl-6-(2 -Methylbenzoyl)-9H-carbazol-3-yl]-,1-(O-acetyloxime) (manufactured by BASF Japan, IRGACURE OXE-02) and other oxime esters; bis(η5-2,4-cyclopentadiene) -1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl)titanium, bis(cyclopentadienyl)-bis[2,6-difluoro-3-(2- (1-Pyr-1-yl)ethyl)phenyl]titanium and other titanocene; . These photopolymerization initiators may be used alone or in combination of two or more.

The amount of such a photopolymerization initiator is preferably 0.01 to 50 parts by mass, more preferably 0.1 to 30 parts by mass, based on 100 parts by mass of the alkali-soluble resin (B) in terms of solid content. preferable.

(Photopolymerization inhibitor)
The photocurable resin composition constituting the dry film of the present invention preferably contains a photopolymerization inhibitor in addition to the components (A), (B), and (C). Scattering (so-called halation) can be suppressed and resolution can be improved.

The photopolymerization inhibitor is not particularly limited, and known and commonly used ones can be used.
Specifically, p-benzoquinone, naphthoquinone, di-t-butyl paracresol, hydroquinone monomethyl ether, α-naphthol, acetamidine acetate, hydrazine hydrochloride, trimethylbenzylammonium chloride, dinitrobenzene, picric acid, quinonedioxime , pyrogallol, tannic acid, resorudin, cupferron, phenothiazine, and the like.
Among them, quinone-based photopolymerization inhibitors such as p-benzoquinone, naphthoquinone, hydroquinone monomethyl ether, and quinonedioxime are preferred.
These photopolymerization inhibitors may be used alone or in combination of two or more.

The amount of such a photopolymerization inhibitor is 0.005 to 20 parts by mass, more preferably 0.01 to 10 parts by mass, per 100 parts by mass of the alkali-soluble resin (B).

[(D) thermosetting compound]
The photocurable resin composition that constitutes the dry film of the present invention contains a thermosetting compound. This thermosetting compound can improve various properties of the cured product, such as heat resistance and insulation reliability, by further thermosetting the photocured composition.
Examples of such thermosetting compounds include known and commonly used thermosetting compounds such as amino resins, melamine resins, maleimide compounds, benzoxazine resins, carbodiimide resins, cyclocarbonate compounds, epoxy compounds, polyfunctional oxetane compounds, and episulfide resins. can be used. Among them, epoxy compounds, oxetane compounds and maleimide compounds are preferably used, and they may be used in combination.

As the epoxy compound, a known and commonly used compound having one or more epoxy groups can be used, and among them, compounds having two or more epoxy groups are preferred. For example, monoepoxy compounds such as butyl glycidyl ether, phenylglycidyl ether, glycidyl (meth)acrylate, bisphenol A type epoxy resin, bisphenol S type epoxy resin, bisphenol F type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin , cycloaliphatic epoxy resin, trimethylolpropane polyglycidyl ether, phenyl-1,3-diglycidyl ether, biphenyl-4,4'-diglycidyl ether, 1,6-hexanediol diglycidyl ether, ethylene glycol or propylene glycol Diglycidyl ether, sorbitol polyglycidyl ether, tris (2,3-epoxypropyl) isocyanurate, triglycidyl tris (2-hydroxyethyl) isocyanurate and other compounds having two or more epoxy groups in one molecule. be done.

As the oxetane compound, a known and commonly used compound having an oxetanyl group can be used. ) oxetane (OXT-211 manufactured by Toagosei Co., Ltd.), 3-ethyl-3-(2-ethylhexyloxymethyl) oxetane (OXT-212 manufactured by Toagosei Co., Ltd.), 1,4-bis {[(3-ethyl-3 -oxetanyl)methoxy]methyl}benzene (OXT-121 manufactured by Toagosei Co., Ltd.), bis(3-ethyl-3-oxetanylmethyl) ether (OXT-221 manufactured by Toagosei Co., Ltd.), and the like. Furthermore, phenol novolac type oxetane compounds and the like are also included. The oxetane compound may be used in combination with the epoxy compound, or may be used alone.

As the maleimide compound, known and commonly used compounds such as polyfunctional aliphatic/alicyclic maleimides and polyfunctional aromatic maleimides can be used. Among them, bifunctional or higher maleimide compounds (polyfunctional maleimide compounds) are preferred.
Polyfunctional aliphatic/alicyclic maleimides include, for example, N,N'-methylenebismaleimide, N,N'-ethylenebismaleimide, tris(hydroxyethyl)isocyanurate and aliphatic/alicyclic maleimide carboxylic acids. isocyanurate skeleton maleimide ester compound obtained by dehydration esterification of isocyanurate skeleton poly(isocyanurate skeleton poly) such as isocyanurate skeleton maleimide urethane compound obtained by urethanizing tris(carbamatehexyl) isocyanurate and aliphatic/alicyclic maleimide alcohol Maleimides; isophorone bisurethane bis(N-ethylmaleimide), triethylene glycol bis(maleimidoethyl carbonate), aliphatic/alicyclic maleimide carboxylic acids and various aliphatic/alicyclic polyols are dehydrated and esterified, or aliphatic Aliphatic/alicyclic polymaleimide ester compounds obtained by transesterification of aliphatic/alicyclic maleimide carboxylic acid esters with various aliphatic/alicyclic polyols; aliphatic/alicyclic maleimide carboxylic acids and various Aliphatic/alicyclic polymaleimide ester compounds obtained by ether ring-opening reaction with aliphatic/alicyclic polyepoxide; and aliphatic/alicyclic polymaleimide urethane compounds obtained by chemical reaction.

Examples of polyfunctional aromatic maleimides include aromatic polymaleimide ester compounds obtained by dehydration esterification of maleimide carboxylic acid and various aromatic polyols, or transesterification of maleimide carboxylic acid esters and various aromatic polyols; Aromatic polymaleimide ester compounds obtained by ether ring-opening reaction of carboxylic acid and various aromatic polyepoxides; Aromatic polymaleimide urethane compounds obtained by urethanization reaction of maleimide alcohol and various aromatic polyisocyanates, etc. and aromatic polyfunctional maleimides.
Among such polyfunctional aromatic maleimides, liquid polyfunctional aromatic maleimides are more preferable in terms of better elongation. Here, the liquid polyfunctional aromatic maleimide is a polyfunctional aromatic having a viscosity of 50,000 cp or less as measured by a cone-plate viscometer (TVH-33H manufactured by Toki Sangyo Co., Ltd.) at 60° C. and 5 rpm. It is called maleimide.

The thermosetting compounds as described above may be used singly or in combination of two or more.
The content of the thermosetting compound is preferably 0.5 to 100 parts by mass, more preferably 1 to 60 parts by mass, based on 100 parts by mass of the alkali-soluble resin (B) in terms of solid content. In particular, when a maleimide compound is blended as a thermosetting compound, the amount of the maleimide compound compounded is preferably 0.1 to 50 parts by mass, based on 100 parts by mass of the alkali-soluble resin (B), in terms of solid content. More preferably, it is 0.2 to 20 parts by mass.

(Thermosetting catalyst)
The photocurable resin composition constituting the dry film of the present invention can contain a thermosetting catalyst in addition to (D) the thermosetting compound. Examples of the thermosetting catalyst include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1 Imidazole derivatives such as -(2-cyanoethyl)-2-ethyl-4-methylimidazole; dicyandiamide, benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethyl Amine compounds such as benzylamine and 4-methyl-N,N-dimethylbenzylamine; hydrazine compounds such as adipic dihydrazide and sebacic acid dihydrazide; and phosphorus compounds such as triphenylphosphine.

Also, 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/isocyanuric acid adducts, 2,4-diamino-6-methacryloyloxyethyl-S-triazine/isocyanuric acid adducts and other S-triazine derivatives, etc. can be used.

Commercially available products include, for example, 2MZ-AP, 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, and 2P4MHZ manufactured by Shikoku Kasei Co., Ltd. (all are trade names of imidazole compounds), U-CAT3503N and U manufactured by San-Apro Co., Ltd. -CAT3502T (all are trade names of dimethylamine blocked isocyanate compounds), 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 promotes the reaction of the thermosetting catalyst for epoxy compounds and oxetane compounds, or other thermosetting components, either alone or in combination of two or more. You can use it.

The content of the thermosetting catalyst is preferably 0.1 to 20 parts by mass, more preferably 0.2 to 20 parts by mass in terms of solid content, per 100 parts by mass of the alkali-soluble resin (B). When the amount of the thermosetting catalyst is within the range of 0.1 to 20 parts by mass, the balance between storage stability and curability is excellent.

(filler)
The photocurable resin composition constituting the dry film of the present invention may optionally contain a filler in order to increase the physical strength of the coating film. As such fillers, known and commonly used inorganic or organic fillers can be used, and barium sulfate, spherical silica, hydrotalcite and talc are particularly preferably used. The amount of the filler compounded is preferably 20 to 200 parts by mass in terms of solid content per 100 parts by mass of the alkali-soluble resin (B).

(Additive)
The photocurable resin composition that constitutes the dry film of the present invention may optionally contain known and commonly used additives. Such additives include coupling agents such as silane coupling agents, adhesion imparting agents, acrylic and silicone leveling agents, antifoaming agents, thermal polymerization inhibitors, ultraviolet absorbers, flame retardants, antistatic agents, A thixotropy-imparting agent and the like can be mentioned.
In addition, if necessary, titanium oxide, metal oxides, and metal hydroxides such as aluminum hydroxide can be blended as extender pigments for the purpose of imparting light reflectivity and flame retardancy.
Further, known and commonly used colorants such as red, blue, green, yellow, white and black can be blended. Any of pigments, dyes, and dyes may be used as the coloring agent.

(Organic solvent)
The photocurable resin composition that constitutes the dry film of the present invention can contain an organic solvent for the purpose of preparing the composition and adjusting the viscosity when the composition is applied to the support film to form a resin layer. .
Examples of the organic solvent include 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, diethylene glycol monomethyl ether acetate, tripropylene glycol monomethyl ether; ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl Esters such as carbitol acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and propylene carbonate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, and solvent naphtha; A known and commonly used organic solvent can be used. These organic solvents may be used individually by 1 type, and may be used in combination of 2 or more type.

[Dry film]
The dry film of the present invention comprises a resin layer obtained by applying a photocurable resin composition to the rough surface side of a support film having a rough surface having an arithmetic mean surface roughness Ra of 100 to 1000 nm and drying the composition. . A dry film having such a structure is laminated on a wiring substrate on which a circuit is formed so that the resin layer faces the substrate side, and pattern exposure is performed from the support film, so that the surface of the exposed portion of the resin layer is exposed to the support. By photocuring along the rough surface shape of the film and then peeling off the support film, the rough surface shape of the support film is transferred to the surface of the resin layer. As a result, the conductor circuit to be wired by SAP performed next can obtain excellent peel strength against the cured product of the resin layer.
In addition, the arithmetic mean surface roughness Ra of the opposite surface of the support film that is not in contact with the photocurable resin composition layer (resin layer) is preferably 300 nm or less. This makes it possible to suppress light scattering during exposure on the opposite surface of the film that is not in contact with the resin layer, and as a result, further improves resolution.

As such a support film, a plastic film is used, and for example, a polyester film such as polyethylene terephthalate (PET), a polyimide film, a polyamideimide film, a polypropylene film, a polystyrene film, or the like can be used. The thickness of this support film is not particularly limited, but is generally selected appropriately within the range of 10 to 150 μm.

The dry film of the invention can be produced, for example, as follows.
First, the above-described photocurable resin composition constituting the dry film of the present invention is diluted with an organic solvent to adjust the viscosity to an appropriate value, and then the composition is coated with a comma coater, blade coater, lip coater, rod coater, squeeze coater, A reverse coater, a transfer roll coater, a gravure coater, a spray coater, or the like is used to apply the composition to a uniform thickness on the support film.
Then, the coating film of the photocurable resin composition applied on the support film was dried at a temperature of 50 to 130° C. for 1 to 30 minutes to form a resin layer composed of the dried coating film on the support film. A dry film can be produced. Here, the thickness of the coating film is not particularly limited, but is generally selected appropriately within the range of 10 to 150 μm, preferably 15 to 60 μm, in terms of film thickness after drying.

The dry film of the present invention produced in this way has a wavelength It is preferable that the light transmittance at 365 nm is 90% or less. By having such light transmittance, the photocurability of the resin layer is stabilized and the resolution is improved.

The dry film of the present invention preferably has a resin layer with a minimum melt viscosity of 10 to 1000 dPa·s at 70°C to 120°C. By having such a melt viscosity, it is possible to obtain sufficient filling properties for circuit irregularities in the laminate.

In the dry film of the present invention, after forming a resin layer made of a photocurable resin composition on a support film, for the purpose of preventing dust from adhering to the surface of the resin layer, the surface of the resin layer is further coated with Preferably, a peelable protective (cover) film is laminated.
As the peelable protective film, any film having an adhesive strength smaller than that between the resin layer and the support film may be used, and for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, or the like can be used.

The dry film of the present invention may be one in which a resin layer is formed by coating and drying a photocurable resin composition on the protective film, and the support film is laminated on the surface of the resin layer. . That is, in the present invention, either a support film or a protective film may be used as the film to which the photocurable resin composition is applied when producing the dry film.

[Cured product]
The cured product of the present invention is obtained by curing the photocurable resin composition of the dry film, and is obtained by photocuring and/or thermal curing.

[Printed wiring board]
The printed wiring board of the present invention has a cured product of the photocurable resin composition that constitutes the dry film of the present invention. The printed wiring board of the present invention can be produced, for example, as follows.
First, the dry film of the present invention is laminated on a wiring substrate having a circuit formed thereon using a laminator or the like so that the resin layer faces the substrate side. In this step, instead of laminating the dry film of the present invention, a liquid photocurable resin composition that constitutes the dry film of the present invention is applied onto a wiring board on which a circuit is formed, dried and tacked. After forming a free resin layer, a support film having a rough surface with an arithmetic mean surface roughness Ra of 100 to 1000 nm is laminated so that the rough surface side faces the resin layer side, thereby forming the dry film of the present invention. It can have the same configuration as the film.
Examples of the wiring board include printed wiring boards and flexible printed wiring boards in which circuits such as copper are formed in advance on various base materials such as glass cloth epoxy and nonwoven fabric epoxy.

Next, the resin layer formed on the wiring board is irradiated with an active energy ray through a photomask having a predetermined pattern on the support film, and pattern exposure is performed, so that the surface of the exposed portion of the resin layer is exposed to the support. By photocuring along the rough surface shape of the film and then peeling off the support film, the rough surface shape of the support film is transferred to the surface of the resin layer.
Here, the exposure device used for the irradiation of the active energy rays may be any device that is equipped with a high-pressure mercury lamp, a metal halide lamp, or the like as a light source and irradiates ultraviolet rays in the range of 350 to 450 nm. Imaging exposure) equipment can also be used. Also, the exposure amount varies depending on the film thickness and the like, but is generally in the range of 10 to 1000 mJ/cm ² , preferably in the range of 20 to 800 mJ/cm ² .

Next, the unexposed area is developed with an alkaline aqueous solution (eg, 0.3 to 3% by mass aqueous solution of sodium carbonate) to form a patterned photocured product.
Here, as a developing method, a dipping method, a shower method, a spray method, or the like can be used, and as a developing solution, an alkaline aqueous solution such as potassium hydroxide, sodium hydroxide, sodium carbonate, or potassium carbonate can be used. can.

Furthermore, the obtained patterned cured product is cured by heating (for example, 100 to 180 ° C.) or by irradiation with active energy rays, resulting in a cured film excellent in various properties such as adhesion and hardness. can be formed. In this manner, an interlayer insulating layer having finer and smaller via hole openings can be formed on the wiring substrate.
Here, heat treatment such as heat curing can be performed using a hot air circulating drying furnace, an IR furnace, or the like.

Further, if necessary, conductive circuits including via holes and interlayer insulating layers are alternately built up, and finally a solder resist is formed to manufacture a printed wiring board.

As described above, the dry film of the present invention is useful as a material for an interlayer insulating layer, but it is also used for forming a pattern layer as a permanent coating for printed wiring boards such as solder resists and coverlays. be able to. In addition, the dry film of the present invention is resistant to development residue, has excellent resolution, and provides excellent adhesion (high peel strength) to conductor circuits formed by SAP. It can also be suitably used as an interlayer insulating material for semiconductor packages that require

The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to the following examples and comparative examples. In the following, "parts" and "%" are based on mass unless otherwise specified.

[Synthesis of compound X]
(Synthesis example 1)
In an eggplant flask equipped with a reflux tube, 100 g of maleic anhydride and 104.2 g of n-hexanol were charged, heated and stirred at 80 ° C. for 24 hours, and had a molecular weight of 200 and a (meth)acryloyl group in one molecule. Thus, a compound A-1 having one carboxyl group was obtained.

(Synthesis example 2)
In an eggplant flask equipped with a reflux tube, 100 g of phthalic anhydride and 68.9 g of n-hexanol were charged, and heated and stirred at 80° C. for 24 hours. A compound A-2 having no carboxyl group and having one carboxyl group was obtained.

(Synthesis Example 3)
In an eggplant flask equipped with a reflux tube, 100 g of phthalic anhydride and 97.4 g of 4-hydroxybutyl acrylate were charged and heated and stirred at 80° C. for 24 hours to obtain a molecular weight of 292 and a (meth)acryloyl group in one molecule. A compound A-3 having a number of 1 and having one carboxyl group was obtained.

(Comparative Synthesis Example 1)
In an eggplant flask equipped with a reflux tube, 100 g of maleic anhydride and 303.9 g of pentaerythritol triacrylate were charged, heated and stirred at 80 ° C. for 24 hours, and the molecular weight was 396, and the number of (meth)acryloyl groups in one molecule. is 3 and the number of carboxyl groups is 1 to obtain a compound Y-1.

(Comparative Synthesis Example 2)
422.5 g of 4,4′-methylenebis(N,N-diglycidylaniline) and 288.2 g of acrylic acid were charged in an eggplant flask equipped with a reflux tube, and heated and stirred at 120° C. for 24 hours. , to obtain a compound Y-2 containing no carboxyl group and having 4 acryloyl groups.

[Synthesis of alkali-soluble resin]
(Synthesis Example 4: Alkali-soluble acrylate-added amideimide resin)
103.5 parts by weight of diethylene glycol monoethyl ether acetate, 222.0 parts by weight of isophorone diisocyanate, and 192.0 parts by weight of trimellitic anhydride were charged into a four-necked flask equipped with a stirrer, thermometer, and condenser while stirring. The temperature was raised to 120°C. Vigorous foaming began at around 60° C., and the contents of the flask gradually became transparent. The reaction was carried out at 120°C for 5 hours, and when the NCO% in the system reached 9.0% by weight, the system was cooled to 40°C. Furthermore, 166.4 parts by weight of diethylene glycol monoethyl ether acetate and 1.0 parts by weight of methyl hydroquinone are added, and 234.7 parts by weight of Aronix M-305 (manufactured by Toagosei, hydroxyl value: 120 KOH-mg/g) is added. , the temperature was raised to 80° C. while paying attention to heat generation. After reacting at 80° C. for 9 hours, it was confirmed in the infrared absorption spectrum that the absorption of isocyanate at 2270 cm ⁻¹ had disappeared, and a pale yellow transparent liquid solution of alkali-soluble resin B-1 was obtained. Molecular weight distribution measurement by GPC revealed a number average molecular weight of 1084 in terms of polystyrene and a weight average molecular weight of 1524 in terms of polystyrene. Also, the acid value was 68.3 KOH-mg/g (in terms of solid content).

(Synthesis Example 5: Phenol-starting alkali-soluble resin)
In an autoclave equipped with a thermometer, a nitrogen introduction device/alkylene oxide introduction device, and a stirring device, 119.4 g of a novolak cresol resin (manufactured by Showa Denko K.K., trade name "Shonol CRG951", OH equivalent: 119.4) was added. , 1.19 g of potassium hydroxide and 119.4 g of toluene were charged, and the inside of the system was replaced with nitrogen while stirring, and the temperature was raised. Next, 63.8 g of propylene oxide was gradually added dropwise and reacted at 125-132° C. and 0-4.8 kg/cm ² for 16 hours. After cooling to room temperature, 1.56 g of 89% phosphoric acid was added to and mixed with the reaction solution to neutralize potassium hydroxide. A propylene oxide reaction solution of a novolak-type cresol resin was obtained. This was obtained by adding an average of 1.08 mol of alkylene oxide per equivalent of phenolic hydroxyl group.
Next, 293.0 g of the alkylene oxide reaction solution of the novolak type cresol resin obtained, 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 air. The mixture was charged into a reactor equipped with a blowing tube, air was blown in at a rate of 10 ml/min, and the mixture was reacted at 110° C. for 12 hours while stirring. 12.6 g of water was distilled out as an azeotrope with toluene, which was produced by the reaction. After cooling to room temperature, the resulting reaction solution was neutralized with 35.35 g of a 15% aqueous sodium hydroxide solution and then washed with water. After that, the toluene was removed by an evaporator while replacing it with 118.1 g of diethylene glycol monoethyl ether acetate to obtain a novolac type acrylate resin solution. Next, 332.5 g of the obtained novolak-type acrylate resin solution and 1.22 g of triphenylphosphine were charged into a reactor equipped with a stirrer, a thermometer and an air blowing pipe, 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 95-101° C. for 6 hours. A resin solution B-2 of a carboxyl group-containing photosensitive resin having a solid acid value of 88 mgKOH/g and a non-volatile content of 65% was obtained.

[Synthesis Example of Compound Having Ethylenically Unsaturated Group]
(Phenol-started alkylene oxide-modified acrylate)
An autoclave equipped with a thermometer, a nitrogen introduction device and an alkylene oxide introduction device, and a stirring device was charged with 106 parts of novolac phenolic resin (manufactured by Showa Denko K.K., hydroxyl equivalent: 106), 2.6 parts of a 50% aqueous sodium hydroxide solution, 100 parts of toluene/methyl isobutyl ketone (mass ratio = 2/1) was charged, the inside of the system was replaced with nitrogen while stirring, the temperature was raised, and 60 parts of propylene oxide was gradually added 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. 3.3 parts of a 36% hydrochloric acid aqueous solution was added to and mixed with this reaction solution to neutralize the sodium hydroxide. This neutralization reaction product was diluted with toluene, washed with water three times, and the solvent was removed by an evaporator to give a hydroxyl equivalent of 164 g/eq. to obtain an alkylene oxide adduct of a novolak-type phenolic resin. In this case, 1 mol of alkylene oxide was added on average per 1 equivalent of hydroxyl group.
164 parts of the alkylene oxide adduct of the obtained novolac-type phenolic resin, 72 parts of acrylic acid, 3.0 parts of p-toluenesulfonic acid, 0.05 parts of hydroquinone monomethyl ether, and 100 parts of toluene were stirred, thermometered, and blown with air. The mixture was charged into a reactor equipped with a tube, stirred while air was blown in, and reacted at 90° C. for 12 hours. After the water generated by the reaction began to distill out as an azeotrope with toluene, the reaction was continued for 5 hours and cooled to room temperature. The resulting reaction solution was washed with a 5% NaCl aqueous solution, toluene was distilled off with an evaporator, and carbitol acetate was added to obtain a resin solution Z of a phenol-started alkylene oxide-modified acrylate having a solid content of 70%. rice field.

(Measurement of arithmetic mean surface roughness Ra of support film)
The arithmetic mean surface roughness Ra of the support film used in this example was measured using a laser microscope VK-8500 (manufactured by Keyence Corporation, measurement magnification × 2000, Z-axis measurement pitch 10 nm). For the transparent film that transmits the laser light, the arithmetic mean surface roughness Ra was measured after the Au sputtering treatment.

(Examples 1 to 7, Comparative Examples 1 to 3)
According to the formulation shown in Table 1 below, each component was blended, premixed with a stirrer, and then kneaded with a three-roll mill to disperse. Photocurable resin compositions of Examples 1 to 7 and Comparative Examples 1 to 3. prepared the product. In addition, the compounding quantity in a table|surface shows a mass part.

＊１：東洋紡社製 ルミラーＸ－４２（二軸延伸ポリエステルフィルム、厚み５０μｍ）
＊２：フタムラ化学社製ＦＯＲ－ＭＰ（二軸延伸ポリプロピレンフィルム、厚み４０μｍ）
＊３：王子エフテックス社製アルファンＭＡ－４２０（二軸延伸ポリプロピレンフィルム、厚さ３５μｍ）
＊４：東洋クロス社製 トークロマットフィルム（フィルム両面Ｒａが４００ｎｍ、厚さ１００μｍ）
＊５：王子エフテックス社製アルファンＥ－２０１Ｆ（二軸延伸ポリプロピレンフィルム、厚さ５０μｍ）
＊６：上記合成例１で合成した分子量が２００でカルボキシル基を１つ含む化合物（固形分１００％）
＊７：上記合成例２で合成した分子量が２５０でカルボキシル基を１つ含む化合物（固形分１００％）
＊８：上記合成例３で合成した分子量が２９２でアクリロイル基を１つ、カルボキシル基を１つ含む化合物（固形分１００％）
＊９：上記比較合成例１で合成した分子量が３９６でアクリロイル基を３つ、カルボキシル基を１つ含む化合物（固形分１００％）
＊１０：上記比較合成例２で合成した分子量が７１１でアクリロイル基を４つ含み、カルボキシル基を含まない化合物（固形分１００％）
＊１１：上記合成例４で合成したアルカリ可溶性アクリレート付加アミドイミド樹脂の樹脂溶液Ｂ－１（固形分４２％）
＊１２：上記合成例５で合成したフェノール出発型アルカリ可溶性樹脂の樹脂溶液Ｂ－２（固形分６５％）
＊１３：日本化薬社製ＮＣ－３０００Ｈ ＣＡ８５（ビフェニルアラルキルタイプエポキシ化合物：カルビトールアセテートの希釈品、固形分８５％）
＊１４：ＤＩＣ社製ＨＰ－７２００Ｌ（脂環式エポキシ化合物；カルビトールアセテートの希釈品、固形分８５％）
＊１５：ＢＡＳＦジャパン社製イルガキュアＴＰＯ（ホスフィンオキサイド系光重合開始剤）
＊１６：ＢＡＳＦジャパン社製イルガキュアＯＸＥ０２（オキシム系光重合開始剤）
＊１７：四国化成社製１Ｂ２ＰＺ（イミダゾール系硬化触媒；１－ベンジル－２－フェニルイミダゾール）
＊１８：川崎化成工業社製ＱＳ－３０（キノン系光重合禁止剤）
＊１９：ＢＹＫ社製ＢＹＫ－３６１Ｎ（ポリアクリレート系表面調整剤）
＊２０：信越化学社製 シランカップリング剤
＊２１：新中村化学工業社製Ａ－ＤＣＰ（２官能；トリシクロデカンジメタノールジアクリレート；分子量３０４）
＊２２：ＢＡＳＦジャパン社製ラロマーＬＲ８８６３（３官能；エチレンオキサイド付加トリメチロールプロパントリアクリレート；分子量約３４０）
＊２３：上記で合成したフェノール出発型アルキレンオキシド変性アクリレート（固形分７０％）
＊２４：和光純薬工業社製 フタロシアニンブルー
＊２５：三菱ケミカル社製 カーボンブラック
＊２６：アドマテックス社製 球状シリカ
＊２７：アドマテックス社製 ナノシリカ
＊２８：堺化学社製 硫酸バリウム
＊２９：協和化学工業社製 ハイドロタルサイト

*1: Lumirror X-42 manufactured by Toyobo Co., Ltd. (biaxially stretched polyester film, thickness 50 μm)
*2: FOR-MP manufactured by Futamura Chemical Co., Ltd. (biaxially oriented polypropylene film, thickness 40 μm)
* 3: Alphan MA-420 manufactured by Oji F-Tex Co., Ltd. (biaxially oriented polypropylene film, thickness 35 μm)
*4: Toyo Cloth Co., Ltd. Tokuchromat film (both sides of the film have a Ra of 400 nm and a thickness of 100 μm)
* 5: Alphan E-201F manufactured by Oji F-Tex Co., Ltd. (biaxially oriented polypropylene film, thickness 50 μm)
*6: A compound having a molecular weight of 200 and containing one carboxyl group synthesized in Synthesis Example 1 above (solid content: 100%)
* 7: Compound containing one carboxyl group with a molecular weight of 250 synthesized in Synthesis Example 2 above (solid content 100%)
*8: A compound having a molecular weight of 292 and containing one acryloyl group and one carboxyl group synthesized in Synthesis Example 3 above (solid content: 100%)
*9: A compound having a molecular weight of 396 and containing three acryloyl groups and one carboxyl group synthesized in Comparative Synthesis Example 1 (solid content: 100%)
*10: A compound having a molecular weight of 711, containing four acryloyl groups, and containing no carboxyl groups (solid content: 100%) synthesized in Comparative Synthesis Example 2 above.
*11: Resin solution B-1 of alkali-soluble acrylate-added amideimide resin synthesized in Synthesis Example 4 above (solid content 42%)
*12: Resin solution B-2 of the phenol-starting alkali-soluble resin synthesized in Synthesis Example 5 above (solid content 65%)
* 13: NC-3000H CA85 manufactured by Nippon Kayaku Co., Ltd. (biphenyl aralkyl type epoxy compound: diluted carbitol acetate, solid content 85%)
*14: HP-7200L manufactured by DIC (alicyclic epoxy compound; diluted carbitol acetate, solid content 85%)
* 15: Irgacure TPO manufactured by BASF Japan (phosphine oxide photopolymerization initiator)
* 16: Irgacure OXE02 manufactured by BASF Japan (oxime-based photopolymerization initiator)
* 17: 1B2PZ manufactured by Shikoku Kasei Co., Ltd. (imidazole-based curing catalyst; 1-benzyl-2-phenylimidazole)
* 18: QS-30 (quinone-based photopolymerization inhibitor) manufactured by Kawasaki Kasei Kogyo Co., Ltd.
*19: BYK-361N manufactured by BYK (polyacrylate-based surface conditioner)
* 20: Shin-Etsu Chemical Co., Ltd. silane coupling agent * 21: Shin-Nakamura Chemical Co., Ltd. A-DCP (bifunctional; tricyclodecane dimethanol diacrylate; molecular weight 304)
* 22: Laromer LR8863 manufactured by BASF Japan (trifunctional; ethylene oxide-added trimethylolpropane triacrylate; molecular weight of about 340)
*23: Phenol-started alkylene oxide-modified acrylate synthesized above (solid content 70%)
*24: Phthalocyanine blue manufactured by Wako Pure Chemical Industries, Ltd. *25: Carbon black manufactured by Mitsubishi Chemical Corporation *26: Spherical silica manufactured by Admatechs *27: Nano silica manufactured by Admatechs *28: Barium sulfate manufactured by Sakai Chemical Co., Ltd. *29: Kyowa Hydrotalcite manufactured by Kagaku Kogyo Co., Ltd.

For the obtained photocurable resin composition of each example and each comparative example, a dry film for evaluation test was prepared using a predetermined support film shown in Table 1, and the resolution, development speed, and developability were evaluated. , adhesion and light transmittance were evaluated. The results are shown together in Table 1.

(Preparation of dry film)
The obtained photocurable resin composition of each example and each comparative example was coated on a predetermined support film shown in Table 1 and dried at 80 ° C. for 20 minutes to obtain a photocurable resin composition having a thickness of 20 μm. A resin layer consisting of a substance was formed. Then, a protective film was laminated on the resin layer to prepare a dry film for evaluation test.

(Resolution)
Peel off the protective film of the dry film for evaluation test obtained in each example and each comparative example, and laminate it at a temperature of 70 ° C. using CVP-300 manufactured by Nikko Materials Co., Ltd. on the wiring board on which the circuit is formed. Then, an evaluation test substrate was produced.
Using a direct imaging exposure apparatus equipped with a high-pressure mercury lamp, this evaluation test substrate was exposed to a pattern with an opening diameter of 25 μmφ at an exposure amount of 170 mJ/cm ² , and then the support film was peeled off, followed by 1% by mass sodium carbonate. Using an aqueous developer, development was carried out for 100 seconds at a spray pressure of 0.2 MPa. Then, it was irradiated with ultraviolet rays in a UV conveyor furnace under the condition of an integrated exposure amount of 1000 mJ/cm ² , and further cured by heating at 180° C. for 60 minutes.
Regarding the wiring board on which the resin layer having the pattern with the opening diameter of 25 μmφ was formed in this way, the top diameter and bottom diameter of the opening were observed and measured at an angle of 45 degrees by SEM, and the resolution was evaluated. The evaluation criteria are as follows.
A: (bottom diameter / top diameter) is 0.8 or more and less than 0.9.
◯: (bottom diameter/top diameter) is 0.7 or more and less than 0.8.
Δ: (bottom diameter/top diameter) is 0.6 or more and less than 0.7.
x: (bottom diameter/top diameter) is less than 0.6.

(Development speed)
For the evaluation test substrate prepared in the evaluation of resolution, the support film was peeled off without exposure, and the developer was developed using a 1% by mass sodium carbonate aqueous solution under conditions of a spray thickness of 0.2 MPa. The development time until the resin layer was completely removed was measured with a stopwatch to evaluate the development speed. The evaluation criteria are as follows.
Good: Developing time is less than 50 seconds.
Δ: Development time is 50 seconds or more and less than 60 seconds.
x: Development time of 60 seconds or more.

(Developability)
Using a direct imaging exposure apparatus equipped with a high-pressure mercury lamp, a pattern with an opening diameter of 25 μmφ is exposed at an exposure amount of 170 mJ/cm ² on the evaluation test substrate prepared in the evaluation of resolution, and then the support film is peeled off. After that, the film was developed using a 1% by mass aqueous solution of sodium carbonate as a developer at a spray pressure of 0.2 MPa for a time twice as long as the development time in the evaluation of the development speed. Then, it was irradiated with ultraviolet rays in a UV conveyor furnace under the condition of an integrated exposure amount of 1000 mJ/cm ² , and further cured by heating at 180° C. for 60 minutes.
With respect to the wiring board on which the resin layer having the pattern with the opening diameter of 25 μmφ was thus formed, the bottom of the opening was observed by SEM to evaluate the developability. The evaluation criteria are as follows.
◯: No residue at the bottom of the opening.
x: Those with residues at the bottom of the opening.

(Adhesion)
Using a direct imaging exposure apparatus equipped with a high-pressure mercury lamp, the entire surface of the evaluation test substrate prepared in the evaluation of resolution was exposed at an exposure amount of 170 mJ/cm ² , and then the support film was peeled off. % sodium carbonate aqueous solution for 50 seconds at a spray pressure of 0.2 MPa. Then, it was irradiated with ultraviolet rays in a UV conveyor furnace under the condition of an integrated exposure amount of 1000 mJ/cm ² , and further cured by heating at 180° C. for 60 minutes.
The wiring substrate (cured resin layer-formed substrate) having the cured resin layer formed on the entire surface in this way is further subjected to a roughening treatment to be described later, and then a conductor layer is formed. A cut is made in a shape of 100 mm, one end of this cut is partially peeled off, and a tensile tester (AGS-G100W manufactured by Shimadzu Corporation) is used to conform to JISK7127, a tensile speed of 1.0 mm / min, 23 ° C. The load (kgf/cm) measured under the conditions of 1 was defined as the peel strength, and the adhesion was evaluated. The evaluation criteria are as follows.
○: The peel strength is 0.3 kgf/cm or more.
Δ: The peel strength is 0.15 kgf/cm or more and less than 0.3 kgf/cm.
x: The peel strength is less than 0.15 kgf/cm.

Roughening treatment The cured resin layer-formed substrate is subjected to swelling liquid Swelling Dip Securigans P (an aqueous solution of glycol ethers and sodium hydroxide) containing diethylene glycol monobutyl ether manufactured by Atotech Japan Co., Ltd. for 60 minutes. °C for 5 minutes. Next, as a roughening liquid, Concentrate Compact P (KMnO4: 60 g/L, NaOH: 40 g/L aqueous solution) manufactured by Atotech Japan Co., Ltd. was used and immersed at 60°C for 10 minutes. Finally, as a neutralizing solution, Reduction Shoryusin Securigant P (aqueous solution of sulfuric acid) manufactured by Atotech Japan Co., Ltd. was used, and immersion was performed at 60° C. for 5 minutes. After that, drying was performed at 80° C. for 30 minutes.

・Formation of conductor layer First, electroless copper plating in the following steps 1 to 6 (copper plating process using a chemical solution manufactured by Atotech Japan Co., Ltd.) on the cured resin layer formed substrate that has been roughened. was applied. The thickness of the formed electroless copper plating layer was 1 μm. Next, the evaluation test substrate on which the electroless copper plating layer was formed was subjected to heat treatment at 150° C. for 30 minutes, followed by electroplating of copper sulfate to form a conductor layer having a thickness of 25 μm. Finally, annealing treatment was performed at 180° C. for 60 minutes, and adhesion was evaluated.
1. Alkali Cleaning (Cleaning the Surface of the Insulating Layer and Adjusting Charge) Cleaning was performed at 60° C. for 5 minutes using Cleaning Cleaner Security 902 (trade name).
2. Soft Etching Process A sulfuric acid-acid sodium peroxodisulfate aqueous solution was used for processing at 30° C. for 1 minute.
3. Pre-dip (adjustment of surface charge of insulating layer for Pd application) step Pre. Dip Neoganth B (trade name) was used for 1 minute at room temperature.
4. Activator Application (Pd Application to the Surface of the Insulating Layer) Process Using Activator Neoganth 834 (trade name), treatment was performed at 35° C. for 5 minutes.
5. Reduction (reduction of Pd applied to the insulating layer) process Reducer Neoganth WA (trade name) and Reducer Accera
Later 810 mod. (trade name) and treated at 30° C. for 5 minutes.
6. Electroless copper plating (Cu is deposited on the surface of the insulating layer (Pd surface)) process Basic Solution Printganth MSK-DK (trade name),
Copper solution Printganth MSK (trade name) and Sta
bilizer Printganth MSK-DK (trade name) and Reducer
A mixed solution with Cu (trade name) was used for treatment at 35° C. for 20 minutes.

(light transmittance)
A dry film having a resin layer made of a photocurable resin composition and having a thickness of 15 μm was produced in the same manner as the dry film. The protective film of this dry film is peeled off and laminated on a glass substrate using CVP-300 manufactured by Nikko Materials Co., Ltd. at a temperature of 70 ° C., and an evaluation test substrate (two layers of a support film and a photocurable resin composition ) was prepared.
The light transmittance at a wavelength of 365 nm was measured for this evaluation test substrate using an ultraviolet-visible spectrophotometer V-670EX manufactured by JASCO Corporation. The evaluation criteria are as follows.
◯: Light transmittance of 90% or less.
x: Light transmittance exceeding 90%.

As is clear from the results shown in Table 1, with respect to Examples 1 to 7 using the dry film of the present invention, resolution (ratio of top diameter to bottom diameter), development speed, developability at the bottom of the opening, adhesion The results were satisfactory for both properties (peel strength) and light transmittance. On the other hand, Comparative Examples 1 and 2, which did not contain compound X, were poor in resolution (ratio of top diameter to bottom diameter), development speed, development performance at the bottom of the opening, and adhesion (peel strength). Moreover, in Comparative Example 3 using a support film having an Ra of 50 nm, sufficient adhesiveness (peel strength) was not obtained.

Claims (5)

A dry film comprising a layer of a photocurable resin composition on the rough surface side of a support film having a rough surface with an arithmetic mean surface roughness Ra of 100 to 1000 nm, wherein the photocurable resin composition is (A ) a compound having 0 to 2 (meth)acryloyl groups and at least one carboxyl group in one molecule and having a molecular weight of 500 or less, and (B) a carboxyl group-containing resin having an acid value of 20 to 120 mgKOH/g , A dry film comprising (C) a photopolymerization initiator and (D) an epoxy compound . 2. The dry film according to claim 1, wherein the support film has an arithmetic mean surface roughness Ra of 300 nm or less on the opposite side that is not in contact with the layer of the photocurable resin composition. 3. The dry film according to claim 1, wherein the dry film has a light transmittance of 90% or less at a wavelength of 365 nm. A cured product obtained by curing the photocurable resin composition for a dry film according to any one of claims 1 to 3. A printed wiring board comprising the cured product according to claim 4 .