JP2003076016A - Photosensitive resin composition and dry film using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition excellent in sensitivity, resolving power, adhesion of thin lines, flexibility as a resist, developing solution resistance and plating property and to provide a laminate of the composition. SOLUTION: The photosensitive resin composition comprises (a) an unsaturated group-free carboxyl-containing polymer, (b) a functional polymer obtained by reacting a specified compound with a carboxyl-containing polymer and having 0.3-3.5 mmol/g unsaturated groups, (c) an ethylenically unsaturated compound and (d) a photopolymerization initiator. A dry film is obtained by using the composition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive resin composition used for patterning printed wiring boards for semiconductor packages, lead frames and the like, and a dry film using the same. More specifically, not only high resolution,
The present invention relates to a photosensitive resin composition that is also excellent in fine wire adhesion, plating characteristics, resist flexibility, and resist releasability, and a dry film using the same.

[0002]

2. Description of the Related Art In recent years, along with the miniaturization of printed wiring boards and the like, a photoresist method using a photosensitive resin has been used for manufacturing printed wiring boards and the like. Most of the dry film resists used in this photoresist method are of the alkali development type, and after exposure, the unexposed parts are removed by developing the unexposed parts with an aqueous alkaline solution such as sodium carbonate to form a resist on the substrate. A pattern is formed. And a known etching method,
Alternatively, the printed wiring board is manufactured by performing etching and resist stripping by a plating method or the like. Particularly, for the purpose of forming a fine pattern, the plating method is advantageous, and in forming the resist pattern in that case, for example, a dry film having a photosensitive resin layer thickness of about 25 μm is used.
Ultra-high resolution capable of resolution of less than 5 μm, and 15 μm
There is a demand for a photosensitive resin composition having a fine line adhesion of less than m.

[0003]

However, in the conventional photosensitive resin composition, the resolution is still insufficient and the adhesiveness to fine lines is inferior, so that the above demand cannot be satisfied. Further, when a fine line pattern is formed on a thin substrate such as a flexible printed wiring board or an electroless plated board, the resist flexibility is inferior and the plating characteristics are still unsatisfactory. In the market, there is a demand for a photosensitive resin composition which has a high resolution, good adhesion to fine lines, and excellent resist flexibility, plating characteristics, and resist releasability.

[0004]

Under the circumstances described above, the present invention examined a photosensitive resin composition excellent in sensitivity, resolution, adhesiveness, resist flexibility, plating characteristics, and resist releasability. As a result, (a) a carboxyl group-containing polymer containing no unsaturated group, (b) a compound represented by the following general formula (1) was reacted with a carboxyl group-containing polymer, and the unsaturated group number was 0.3 to 3.5 mmol / g. A functional polymer [hereinafter sometimes simply referred to as (b) functional polymer], (c) ethylenically unsaturated compound,
The inventors have found that a photosensitive resin composition containing a photopolymerization initiator (d) meets the above-mentioned object, and completed the present invention.

[0005]

[Chemical 2] [Where R₁Is hydrogen or a methyl group, R₂Is-[(CO)_x
CHX₁(CHX₂)_yO] _z-(Where x is 0 or 1, y
Is an integer of 0-9, z is an integer of 1-10, X₁, X₂Is hydrogen
Or methyl group), R₃2 diisocyanates
An organic residue excluding a cyanate group is shown. ]

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The (a) carboxyl group-containing polymer used in the present invention is an acrylic copolymer mainly composed of (meth) acrylic acid ester, to which an ethylenically unsaturated carboxylic acid is copolymerized. It is preferably used,
Furthermore, if necessary, an acrylic copolymer obtained by copolymerizing another copolymerizable monomer can be used, and it does not contain an unsaturated bond in the molecule.

Examples of the (meth) acrylic acid ester include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, and 2
-Ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, lauryl (meth) acrylate, dimethylaminoethyl (meth) acrylate, hydroxyethyl (meth)
Acrylate, hydroxypropyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylic acid tetrahydrofurfuryl ester, (meth) acrylic dimethylaminoethyl ester, (meth) acrylic acid diethylaminoethyl ester, methacrylic acid glycidyl ester, 2, 2,2-trifluoroethyl (meth)
Acrylate and 2,2,3,3-tetrafluoropropyl (meth) acrylate acrylamide are mentioned.

As the ethylenically unsaturated carboxylic acid, for example, monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid are preferably used, and other dicarboxylic acids such as maleic acid, fumaric acid and itaconic acid, or those thereof. Anhydrides and half esters can also be used. Among these, acrylic acid and methacrylic acid are particularly preferable.

Examples of other copolymerizable monomers include (meth) acrylamide, diacetone acrylamide, styrene, α-methylstyrene, vinyltoluene,
Examples thereof include vinyl acetate, alkyl vinyl ether, and (meth) acrylonitrile.

(A) The weight average molecular weight of the carboxyl group-containing polymer containing no unsaturated group is 15,000 to 80.
000 is preferable, and further, those in the range of 25,000 to 75,000 are advantageous. When the molecular weight is less than 15,000, resist flexibility may be poor, and when it exceeds 80,000, the photosensitive resin composition may have poor developability. It is not preferable because it may lower the resolution and may lower the resolution or the resist releasability.

(A) The acid value of the carboxyl group-containing polymer having no unsaturated group is 100 to 240 mg KO.
H / g is preferable, and further 110 to 190 mg KOH /
It is g. If the acid value is less than 100 mgKOH / g, the releasability of the resist may be insufficient, and 240 m
If it exceeds gKOH / g, the fine line adhesion of the resist pattern may be poor, which is not preferable.

Next, the (b) functional polymer used in the present invention will be described. The functional polymer (b) is obtained by introducing a compound represented by the following general formula (1) into a carboxyl group-containing polymer,
It is a polymer adjusted so that the number of unsaturated groups in (b) is 0.3 to 3.5 mmol / g.

[0013]

[Chemical 3] [Where R₁Is hydrogen or a methyl group, R₂Is-[(CO)_x
CHX₁(CHX₂)_yO] _z-(Where x is 0 or 1, y
Is an integer of 0-9, z is an integer of 1-10, X₁, X₂Is hydrogen
Or methyl group), R₃2 diisocyanates
An organic residue excluding a cyanate group is shown. ]

The unsaturated radical number is 0.3 to 3.5 mmo.
It is necessary to set it to 1 / g, and preferably 1.0 to 3.2.
mmol / g, more preferably 1.5-3.2 mmol / g. If the number of unsaturated groups is less than 0.3 mmol / g, the thin line adhesion of the resist pattern will be poor, and 3.5 mmol / g
If it exceeds g, the releasability of the resist is inferior and unsuitable.

Examples of the carboxyl group-containing polymer used in the production of the functional polymer (b) include the acrylic copolymers described in (a), but the acid value and the weight average molecular weight are not particularly limited. Not something. The compound represented by the general formula (1) is obtained by reacting the compound represented by the general formula (2) and diisocyanate in equimolar amounts.

[0016]

[Chemical 4] [Where R₁Represents hydrogen or a methyl group, and R₂Is-[(C
O)_xCHX₁(CHX₂)_yO]_z-(However, x is 0 or
1, y is an integer of 0-9, z is an integer of 1-10, X ₁, X₂
Represents hydrogen or a methyl group). ]

Specific examples of the compound represented by the general formula (2) include (poly) ethylene glycol mono (meth) acrylate, (poly) propylene glycol mono (meth) acrylate, and (poly) butylene glycol mono (meth). ) Acrylate, glycol mono (meth) acrylate, polycarbitol mono (meth) acrylate and the like.

The diisocyanate may be aromatic, aliphatic, cycloaliphatic or alicyclic diisocyanate or a mixture thereof, among which 2,4-tolylene diisocyanate or 2,6-tolylene diisocyanate. Tolylene diisocyanate (TDI), and mixtures thereof, hydrogenated TDI, 4,4′-diphenylmethane diisocyanate (MDI), hydrogenated MDI, crude M
DI, modified MDI, xylylene diisocyanate (XD
I), hydrogenated XDI, tetraxylylene diisocyanate (TMXDI), isophorone diisocyanate (IPD
I), norbornene diisocyanate (NBDI), tolylene diisocyanate dimer (TT), hexamethylene diisocyanate (HMDI), trimethylhexamethylene diisocyanate (TMHMDI), o-tolidine diisocyanate (TODI), naphthalene diisocyanate (NDI), diphenyl ether diisocyanate (TN). PEDI), dianisidine diisocyanate (DADI), p-phenylene diisocyanate (PP
DI), isopropylidene bis-4-cyclohexyl diisocyanate (IPCI), lysine diisocyanate methyl ester (LDI), trimethylhexamethylene diisocyanate (TMDI), dimer acid diisocyanate (DDI), ethylene diisocyanate, and hexamethylene diisocyanate ( HMD
I) 2,4-Tolylene diisocyanate, isophorone diisocyanate (IPDI), norpornene didisocyanate (NBDI), ethylene diisocyanate are preferably used.

The molecular weight of the compound represented by the general formula (1) is preferably about 150 to 1000. If it is less than 150, the effect of imparting flexibility to the resist may be lowered, and if it exceeds 1000, the effect of improving the fine line adhesion may not be obtained unless it is reacted with the carboxyl group-containing polymer in a large amount, which is not preferable.

In order to produce the functional polymer (b) by reacting the compound represented by the general formula (1) thus obtained with the carboxyl group-containing polymer, the presence of a catalyst such as dibutyltin laurate or dibutyltin maleate. under,
In a solvent such as methyl ethyl ketone, toluene, xylene, ethyl acetate, and acetone at 20 to 80 ° C., 0.5 to
Both may be reacted for 20 hours, and the reaction rate of the compound represented by the general formula (1) at that time is adjusted to about 5 to 80 mol% of the carboxyl groups in the carboxyl group-containing polymer, and finally ( b) The acid value of the functional polymer is 3
It may be 0 to 160 mgKOH / g. The acid value is preferably 35 to 140 mgKOH / g. If the acid value is less than 30 mgKOH / g, the resist releasability may be inferior, and if it exceeds 160 mgKOH / g, (a) the compatibility with the carboxyl group-containing polymer not containing an unsaturated group becomes poor and the smoothness of the resist pattern becomes poor. It is inferior and not preferable.

The weight average molecular weight of the functional polymer (b) is preferably 6500 to 60,000, more preferably 9000 to 40,000, and the molecular weight is 65.
When it is less than 00, flexibility is poor, and when it exceeds 60000, developability is lowered, and (a) compatibility with a carboxyl group-containing polymer not containing an unsaturated group is poor, resulting in poor smoothness of the resist pattern. Is not preferable.

The ethylenically unsaturated compound (c) used in the present invention is not particularly limited and may be either a single component system or a composite component system, but the component contains an acrylic compound having a urethane bond. It is preferable to improve the flexibility of the resist after exposing the photosensitive resin composition. The weight average molecular weight of the acrylic compound is not particularly limited, but is preferably about 800 to 20,000, and more preferably 1,000 to 5,000. If the weight average molecular weight is less than 800, the effect of imparting flexibility to the resist may be lowered, and if it exceeds 20,000, the fine line adhesion of the resist pattern may be lowered, which is not preferable. Specific examples of such acrylic compounds include those having the structures of the following general formulas (3) to (6).

[0023]

[Chemical 5]

[0024]

[Chemical 6]

[0025]

[Chemical 7]

[0026]

[Chemical 8]

In the above general formulas (3) to (6), R ₄
Is hydrogen or an alkyl group having 1 to 3 carbon atoms, R ₅ , R ₆ ,
R ₇ and R ₈ are each independently an alkylene group having 2 to 5 carbon atoms,
X and Y are divalent hydrocarbon groups having 2 to 20 carbon atoms, 1, m,
n independently represents an integer of 0 to 30.

The acrylic compound having a urethane bond is preferably contained in the ethylenically unsaturated compound component (c) in an amount of 1 to 45% by weight, particularly preferably 3 to 20% by weight. If the content is less than 1% by weight, the effect of imparting flexibility to the resist may be insufficient, and if it exceeds 45% by weight, the resolution may deteriorate, which is not preferable.

(C) The ethylenically unsaturated compound other than the acrylic compound having a urethane bond in the ethylenically unsaturated compound component is not particularly limited, and polyfunctional monomers and monofunctional monomers may be used alone or in combination. As the functional monomer, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexane glycol di (meth) acrylate, Glycerin di (meth) acrylate, pentaerythritol di (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di (meth) acrylate, β-hydroxy ether Le -β'- acryloyloxyethyl -o- phthalate, phthalic acid diglycidyl ester di (meth) acrylate, hydroxy lark phosphate-modified neopentyl glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate,
Trimethylolpropane triethoxytriacrylate, trimethylolpropane tripropoxytriacrylate, 1,6-hexamethyldiglycidyl ether di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipenta Erythritol penta (meth) acrylate, (poly) propoxypentaerythritol tetra (meth) acrylate, (poly) ethoxy pentaerythritol tetra (meth) acrylate, glycerin (poly) propoxy (meth) acrylate, glycerin (poly) ethoxy (meth) acrylate , Glycerin polyglycidyl ether poly (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol Ruhekisa (meth) acrylate, 2,2'-bis (4- (meth) acryloxydiethoxyphenyl) propane, 2,2'-bis (4- (meth) acryloxy pentaethoxy phenyl) propane,
2,2'-bis (4- (meth) acryloxypolyethoxyphenyl) propane, 2-hydroxy-3- (meth)
Examples thereof include acryloyloxypropyl acrylate and trimethylolpropane triglycidyl ether tri (meth) acrylate. Among these, 2,2′-bis (4- (meth) acryloxydiethoxyphenyl) propane and 2,2′-bis (4- (meth) acryloxypentaethoxyphenyl) propane, 2,2'-bis (4-
(Meth) acryloxypolyethoxyphenyl) propane trimethylolpropane di (meth) acrylate, trimethylolpropane triethoxytriacrylate, trimethylolpropane tripropoxytriacrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) Acrylate,
Dipentaerythritol penta (meth) acrylate,
(Poly) propoxypentaerythritol tetra (meth) acrylate and (poly) ethoxypentaerythritol tetra (meth) acrylate are preferable.

As monofunctional monomers, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and 2-hydroxybutyl (meth)
Acrylate, 2-phenoxy-2-hydroxypropyl (meth) acrylate, 2- (meth) acryloyloxy-2-hydroxypropyl phthalate, 2- (meth) acroyloxyethyl-2-hydroxyethyl phthalate, 3-chloro-2 -Hydroxypropyl (meth) acrylate, glycerin mono (meth) acrylate, 2- (meth) acryloyloxyethyl acid phosphate, half (meth) acrylate of phthalic acid derivative, N-methylol (meth) acrylamide, diethylaminoethyl methacrylate, polypropylene glycol (Meth) acrylate, alkylphenol polyethoxy (meth) acrylate, nonylphenol tetraethoxy acrylate, caprolactone-modified (meth) acrylate and the like, Among these 2- (meth) acryloyloxy-2-hydroxypropyl phthalate,
2- (meth) acroyloxyethyl-2-hydroxyethyl phthalate is preferred.

Examples of the photopolymerization initiator (d) in the present invention include benzoin compounds, benzophenone compounds, acetophenone compounds, hexaarylbiimidazole compounds, thioxanthone compounds, benzotriazole compounds, triazine compounds, acridine compounds, benzoyl compounds, benzyl compounds, Sulfone compound, phenylglyoxylate, α-hydroxyisobutylphenone,
Dibenzosparone, 1- (4-isopropylphenyl)
-2-hydroxy-2-methyl-1-propanone, 2-
Methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, diacetyl, anthraquinone, naphthoquinone, triphenylphosphine can be mentioned, and one or more of these can be used. It is preferable to use a rubiimidazole compound from the viewpoint of improving the resolution and the adhesion to fine lines. Examples of the benzoin compound include benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, and benzoin phenyl ether. Examples of the benzophenone compound include 3,3′-dimethyl-4-methoxybenzophenone, benzophenone, p, p′-bis (dimethylamino) benzophenone and p, p′-bis (diethylamino) benzophenone. As the acetophenone compound, 1,1-dichloroacetophenone, pt
-Butyldichloroacetophenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-dichloro-4-phenoxyacetophenone and tetraalkylaminobenzophenone.

As the hexaarylbiimidazole compound, 2,2'-bis (o-chlorophenyl) -4,
5,4 ', 5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis (o-chlorophenyl) -4,
5,4 ', 5'-Tetraphenyl-1,1'-biimidazole, 2,2'-bis (o-fluorophenyl)-
4,5,4 ', 5'-Tetraphenyl-1,1'-biimidazole, 2,2'-bis (o-methoxyphenyl)
-4,5,4 ', 5'-Tetraphenyl-1,1'-biimidazole, 2,2'-bis (p-methoxyphenyl) -4,5,4', 5'-tetraphenyl-1, 1 '
-Biimidazole, 2,4,2 ', 4'-bis [bi (p
-Methoxyphenyl)]-5,5'-diphenyl-1,
1'-biimidazole, 2,2'-bis (2,4-dimethoxyphenyl) -4,5,4 ', 5'-diphenyl-
1,1'-biimidazole, 2,2'-bis (p-methylthiophenyl) -4,5,4 ', 5'-diphenyl-
Examples include 1,1′-biimidazole and bis (2,4,5-triphenyl) -1,1′-biimidazole.

As the thioxanthone compound, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4
-Diethylthioxanthone. Examples of the benzotriazole compound include 1,2,3-benzotriazole, 1-chloro-1,2,3-benzotriazole and 4
-Carboxy-1,2,3-benzotriazole, 5-
Carboxy-1,2,3-benzotriazole, bis (N-2-ethylhexyl) aminomethylene-1,2,
Examples thereof include 3-benzotriazole, bis (N-2-ethylhexyl) aminomethylene-1,2,3-tolyltriazole, and bis (N-2-hydroxyethyl) aminomethylene-1,2,3-benzotriazole.

As the triazine compound, 2,4,6-
Tris (trichloromethyl) -s-triazine, 2-phenyl-4,6-bis (trichloromethyl) -s-triazine, 2-methyl-4,6-bis (trichloromethyl) -s-triazine, 2-n- Propyl-4,6-bis (trichloromethyl) -s-triazine, 2- (p-
Chlorophenyl) -4,6-bis (trichloromethyl)
-S-triazine, 2- (p-tolyl) -4,6-bis (trichloromethyl) -s-triazine, 2,4-bis (trichloromethyl) -4'-methoxyphenyl-s-
Triazine, 2- (4-methoxy-naphth-1-yl)
-4,6-bis (trichloromethyl) -s-triazine, 2- (4-ethoxy-naphth-1-yl) -4,6
-Bis (trichloromethyl) -s-triazine, 2-
[4- (2-Ethoxyethyl) -naphth-1-yl]-
4,6-bis (trichloromethyl) -s-triazine,
2- (4,7-dimethoxy-naphth-1-yl) -4,
6-bis (trichloromethyl) -s-triazine, 2-
(Acenaphtho-5-yl) -4,6-bis (trichloromethyl) -s-triazine, 2- (2 ', 4'-dichlorophenyl) -4,6-bis (trichloromethyl) -s
-Triazine, 2-n-nonyl-4,6-bis (trichloromethyl) -s-triazine, 2- (α, α, β-
Trichloroethyl) -4,6-bis (trichloromethyl) -s-triazine, 2-styryl-4,6-bis (trichloromethyl) -s-triazine, 2-p-methylstyryl-4,6-bis (trichloro) Methyl) -s-
Examples include triazine and 2-p-methoxystyryl-4,6-bis (trichloromethyl) -s-triazine.
Examples of the acridine compound include 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-prolupanone acridine and 9-phenylacridine.
Examples of the benzoyl compound include benzoylbenzoic acid, methyl benzoylbenzoate, and 2-benzoyl-2-dimethylamino-1- [4-morpholinophenyl] -butane. Examples of the benzyl compound include benzyldiphenyldisulfide and benzyldimethylketal. , Dibenzyl. Examples of the sulfone compound include tribromophenyl sulfone and tribromomethylphenyl sulfone.

The blending amounts of (a), (b), (c) and (d) in the photosensitive resin composition of the present invention will be described. The weight ratio of (a) and (b) is 30/70 to 90 /.
10 is preferable, and more preferably 50/50 to 80/20. If the weight compounding ratio is less than 30/70, the flexibility and releasability of the resist may be poor, and if it exceeds 90/10, the fine line adhesion may be poor, which is not preferable.

The compounding amount of (c) is preferably 25 to 400 parts by weight, more preferably 50 to 150 parts by weight, based on 100 parts by weight of the total amount of (a) and (b). Two
If it is less than 5 parts by weight, the adhesion to fine wires may be poor, and if it exceeds 400 parts by weight, the resist releasability may be poor, which is not preferable.

The blending amount of (d) is (a), (b),
0.1 to 10 parts by weight, preferably 1.0 to 8.0 parts by weight, and more preferably 2.0 to 10 parts by weight based on 100 parts by weight of the total amount of (c).
It is 5.0 parts by weight. If the blending amount is less than 0.1 parts by weight, the sensitivity is low and the practicability is poor. If the blending amount exceeds 10 parts by weight, the adhesion is lowered and the developing tank is contaminated, which is not preferable.

The photosensitive resin composition of the present invention contains the above-mentioned components as essential components, but if necessary, a plasticizer, a dye, a pigment, a color-changing agent, an adhesion-imparting agent, an antioxidant, a solvent, a surface tension modifier. Known auxiliaries such as a denaturing agent, a stabilizer, a chain transfer agent, a defoaming agent, a flame retardant, and a thermal polymerization inhibitor can be appropriately added.

The photosensitive resin composition of the present invention is preferably used as a dry film, and the production of such a dry film will be described. The film is formed by sequentially laminating a support film, a photosensitive resin composition layer and a protective film.

The support film preferably has heat resistance and solvent resistance when forming the photosensitive resin composition layer, and examples thereof include a polyester film such as polyethylene terephthalate and a polyimide film. The thickness of the support film varies depending on the material of the film, but is usually about 3 to 50 μm.

The protective film is formed on the photosensitive resin composition layer for the purpose of preventing transfer of the adhesive photosensitive resin composition layer to the support film when the dry film is used in a roll form. Used by stacking. Examples of such a protective film include a polyester film, a polyethylene film, a polypropylene film, a polytetrafluoroethylene film and the like. Further, the thickness of the protective film is not particularly limited,
Usually, 10 to 50 μm is preferable, and further 10 to 30 μm
Is.

The photosensitive resin composition layer is formed on the support film by a conventional method such as a dip coating method, a flow coating method or a screen printing method to form a photosensitive resin composition layer. It is also possible to use a solvent such as methyl ethyl ketone, isopropanol, ethyl acetate, butyl acetate, propylene glycol monomethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, cyclohexane, or methyl cellosolve at the time of coating. The thickness of the photosensitive resin composition layer is usually preferably 5 to 50 μm,
Further, 6 to 40 μm, particularly 7 to 35 μm is advantageous. When the thickness is less than 5 μm, the coating becomes non-uniform or pinholes are apt to occur during coating and drying, and when it exceeds 50 μm, the sensitivity is lowered and the developability is lowered, which is not preferable. .

Next, a method for manufacturing a printed wiring board using the above dry film will be described. Examples of the substrate for forming the pattern include electrolytic copper foil substrates, electroless copper-plated substrates, sputtered copper foil substrates, and the like, and the present invention is characterized by being applicable to electroless copper-plated substrates having a thin copper layer. is there. The electroless copper-plated substrate is 100 to 100.
Insulating material is pasted on 0 μm thick base material, and 0.5
It is a substrate plated with copper of about 3 μm.

(Exposure) To form an image with a dry film, the adhesive strength between the support film and the photosensitive resin composition layer and the adhesive strength between the protective film and the photosensitive resin composition layer are compared to determine the adhesive strength. After peeling off the lower film, the photosensitive resin composition layer side is attached to a metal surface such as a copper surface of the substrate, and then a pattern mask is brought into close contact with the other film for exposure. When the photosensitive resin composition does not have tackiness, the other film may be peeled off and then the pattern mask may be brought into direct contact with the photosensitive resin composition layer for exposure. In the case of proximity exposure and projection exposure, the pattern mask is exposed without contact. In the case of laser exposure, direct imaging (direct exposure) may be used without using a pattern mask.

The exposure is usually carried out by ultraviolet irradiation, and as the light source at that time, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, a chemical lamp, an argon laser and the like are used. After irradiation with ultraviolet rays, heating can be performed as necessary to achieve complete curing.

(Development) After exposure, the film on the resist is peeled off and developed. Since the photosensitive resin composition of the present invention is a dilute alkali developing type, the development after exposure is
Alkali concentration of sodium carbonate, potassium carbonate, etc. is 0.3-
It is performed using a dilute aqueous solution of about 2% by weight. A surface active agent, a defoaming agent, and a small amount of an organic solvent for accelerating the development may be mixed in the alkaline aqueous solution.

(Etching, Plating) Etching is usually carried out by an ordinary method using an acidic etching solution such as cupric chloride-hydrochloric acid aqueous solution or ferric chloride aqueous solution. In rare cases, an ammonia-based alkaline etching solution is also used. In the plating method, after pretreatment using a plating pretreatment agent such as a degreasing agent or a soft etching agent, plating is performed using a plating solution. Examples of the plating solution include a copper plating solution, a nickel plating solution, a gold plating solution, a tin plating solution, and a solder plating solution. INDUSTRIAL APPLICABILITY The photosensitive resin composition of the present invention is particularly effective when a plating method is used, has good plating coverage, and has an excellent anti-plating effect.

(Peeling Removal of Hardened Resist) After the etching step or the plating step, the remaining hardened resist is peeled off. The cured resist is peeled and removed by using an alkali peeling solution made of an aqueous solution having an alkali concentration of about 0.5 to 5% by weight such as sodium hydroxide and potassium hydroxide.
In some cases, an organic release agent containing an amine compound as a main component, such as an aqueous monoethanolamine solution, may be used.

[0049]

The present invention will be described in more detail below with reference to examples. Unless otherwise specified, “%” and “part” are based on weight. Examples 1 to 5 and Comparative Examples 1 to 5 (a) As a carboxyl group-containing polymer, the following (a)
1) or (a2), (b) a functional polymer (b1) to (b5), (c) an ethylenically unsaturated compound (c1) to (c5), (d) a photopolymerization initiator Using (d1) or (d2) and other additives,
A photosensitive resin composition having the composition shown in Table 1 was prepared (diluted with methyl ethyl ketone to have a solid content of 53%).

(A1): Methyl methacrylate / n-butyl methacrylate / styrene / methacrylic acid = 42 /
A 45% methyl ethyl ketone / isopropanol (weight ratio 90/10) solution of a carboxyl group-containing polymer having a composition of 25/10/23 (weight ratio), a weight average molecular weight of 52,000, and an acid value of 150 mgKOH / g.

(A2): Methyl methacrylate / n-butyl methacrylate / methacrylic acid = 42/35/23
(Weight ratio) composition, weight average molecular weight 27,000,
45% methyl ethyl ketone / isopropanol (weight ratio 90/10) solution of a carboxyl group-containing polymer having an acid value of 151 mgKOH / g

(B1): a copolymer composition of 690 parts of an equimolar reaction product of isophorone diisocyanate and diethylene glycol monomethacrylate (molecular weight 385), methyl methacrylate / 2-hydroxyethyl methacrylate / methacrylic acid (5/70/25) 620 parts of a methyl ethyl ketone solution (solid content 50%) of a carboxyl group-containing polymer (acid value 163 mgKOH / g, weight average molecular weight 10000) is mixed, and 0.2 part of dibutyltin laurate and 0.2 part of hydroquinone monomethyl ether are added. Then, the reaction product was reacted with 10 mol% of the carboxyl groups in the carboxyl group-containing polymer to obtain a weight average molecular weight of 32,000 and an acid value of 46 mgKOH /
g, a functional polymer having an unsaturated group number of 1.8 mmol / g

(B2): 690 parts of an equimolar reaction product of isophorone diisocyanate and 2-hydroxypropyl methacrylate (molecular weight 367), methyl methacrylate / 2
-Hydroxyethyl methacrylate / methacrylic acid (5
/ 70/25) copolymerized composition of carboxyl group-containing polymer (acid value 163 mgKOH / g, weight average molecular weight 10000) in methyl ethyl ketone (solid content 50
%) 620 parts, and reacted in the same manner as in (b1) to obtain a weight average molecular weight of 31,000 and an acid value of 48 mg KO.
H / g, functional polymer with unsaturated group number of 1.9 mmol / g

(B3): 600 parts of an equimolar reaction product of isophorone diisocyanate and diethylene glycol monomethacrylate (molecular weight 385), methyl methacrylate /
Mix 800 parts of a methyl ethyl ketone solution (solid content 50%) of a carboxyl group-containing polymer (acid value 293 mg KOH / g, weight average molecular weight 15000) having a copolymer composition of 2-hydroxyethyl methacrylate / methacrylic acid (10/45/45). Then, the mixture was reacted in the same manner as in (b1) to obtain a weight average molecular weight of 38,000 and an acid value of 104 m.
Functional polymer having gKOH / g and unsaturated group number of 1.6 mmol / g

(B4): 40 parts of an equimolar reaction product of isophorone diisocyanate and diethylene glycol monomethacrylate (molecular weight 385), methylmethacrylate /
Mix 1900 parts of a methyl ethyl ketone solution (solid content 50%) of a carboxyl group-containing polymer (acid value 163 mg KOH / g, weight average molecular weight 10000) having a copolymer composition composed of 2-hydroxyethyl methacrylate / methacrylic acid (5/70/25). Then, a weight average molecular weight of 10400 and an acid value of 156 mg KO obtained by reacting in the same manner as in (b1) except that 0.2 mol% of the carboxyl group in the carboxyl group-containing polymer was reacted with the above reaction product.
H / g, functional polymer of unsaturated group number 0.1 mmol / g

(B5): Copolymer having a copolymer composition of 560 parts of 2-isocyanatoethyl methacrylate (molecular weight 155) and ethyl acrylate / acrylic acid (85/15) (acid value 117 mgKOH / g, weight average molecular weight 1
3000) methyl ethyl ketone solution (solid content 50%)
Weight average molecular weight 29100 obtained by reacting in the same manner as in (b1) except that 930 parts were mixed and 30 mol% of the carboxyl groups in the carboxyl group-containing polymer was reacted with 2-isocyanatoethyl methacrylate. , Acid value 37 mg KOH / g, unsaturated group number 3.6 mmol / g
Functional polymer

[0057] _{(c1): [CH 2 =} C (CH 3) -COO- (CH 2 CH 2 O) 5 -
_{CONH-C 6 H 12 -NHCOO- (} CH 2 CHCH
_{3 O) 5 -C 6 H 4} ] 2 -C (CH 3) 2

(C2): [CH ₂ = C (CH ₃ ) -COO- (C ₂ H ₄ O) _6- (C _{5
H 10 COO) 4 -CONH-C} 6 H 12 -NHCOO] 2 -
(CH ₂ CHCH ₃ O) ₁₅

(C3): 2,2-bis (4- (methacryloxypolyethoxy) phenyl) propane (10 ethoxy groups) (c4): trimethylolpropane tripropoxytriacrylate (c5): 2-acryloyloxyethyl-2 -Hydroxyethyl phthalate

(D1): 2,2'-bis (o-chlorophenyl) -4,5,4 ', 5'-tetraphenyl-1,
2'-biimidazole (d2): 4,4'-bis (diethylamino) benzophenone

Other additives (LCV): Leuco Crystal Violet (MG): Malachite green

[Table 1] (a) (b) (c) (d) a1 a2 b1 b2 b3 b4 b5 c1 c2 c3 c4 c5 d1 d2 LCV MG Example 1 42 0 15 0 0 0 0 7 0 21 6 5 3.5 0.1 0.3 0.1 〃 2 42 0 0 15 0 0 0 7 0 21 6 5 3.5 0.1 0.3 0.1 〃 3 42 0 15 0 0 0 0 0 7 21 6 5 3.5 0.1 0.3 0.1 〃 4 42 0 0 0 15 0 0 7 0 21 6 5 3.5 0.1 0.3 0.1 〃 5 0 42 15 0 0 0 0 7 0 21 6 5 3.5 0.1 0.3 0.1 Comparative example 1 0 0 57 0 0 0 0 7 0 21 6 5 3.5 0.1 0.3 0.1 〃 2 57 0 0 0 0 0 0 7 0 21 6 5 3.5 0.1 0.3 0.1 〃 3 42 0 0 0 0 15 0 7 0 21 6 5 3.5 0.1 0.3 0.1 〃 4 42 0 0 0 0 0 15 7 0 21 6 5 3.5 0.1 0.3 0.1 〃 5 42 0 54 0 0 0 0 0 0 0 0 0 3.5 0.1 0.3 0.1 The blending amount (part) of each component is a solid content display.

Next, each dope was coated on a polyester film having a thickness of 16 μm using an applicator and left at room temperature for 1 minute and 30 seconds, then 60 ° C. for 2 minutes and 90 ° C. for 2 minutes.
Min., 105 ° C. for 1 minute, and dried with hot air to obtain a dry film having a resist thickness of 25 μm (no protective film provided). The following evaluation was performed using the obtained dry film. Incidentally, regarding the evaluation of sensitivity, resolution, fine line adhesion, developer resistance, resist peeling property, plating penetration, and plating coverage, the surface roughness was Ra = 0.25 for the substrate (total thickness 0.8 mm). ˜0.3 μm, R _max = 2.
An electrolessly plated double-sided substrate of 0 to 3.5 μm was immersed in 5% sulfuric acid at room temperature for 30 seconds, washed with water and dried, and the dry film was laminated on the substrate preheated to 60 ° C. in advance. 110 ℃, same roll pressure 4kg / cm
^{2. A} laminate obtained by laminating at a laminating speed of 1.2 m / min was prepared. The results are shown in Tables 2 and 3.

(Sensitivity) A pattern mask was placed on the polyester film of the obtained laminate, and a 5 kW mercury short arc lamp (parallel light) was used. It was measured.

(Resolution) A pattern mask [line / space = 1 / on the polyester film of the obtained laminate
1 (6, 8, 10, 12, 14, 16, 18, 2 respectively)
Glass chrome dry plate (0, 25, 30, 35, 40 μm) is placed and the polyester film is peeled off 15 minutes after exposure with the exposure amount obtained above and sprayed with a 1% sodium carbonate aqueous solution at 30 ° C. Then, development was carried out for twice as long as the break point to form a line pattern, and the minimum line width (μm) was examined.

(Thin line adhesion) In the evaluation of resolution, line widths of 6, 8, 10, 12, 1 are used as pattern masks.
The same development was carried out in the same manner except that a glass chrome dry plate having independent fine lines of 4, 16, 18, 20, 25, 30, 35, 40 μm was used, and the minimum line width (μm) with good adhesion of the line pattern was examined.

(Developer resistance) In the evaluation of fine line adhesion, the minimum line width (μm) with good adhesion of the line pattern was examined in the same manner except that development was carried out at 4 times the break point.

(Resist releasability) A pattern mask [line / space = 1/1 (6, 8, 10, 12, 14, 16, 1 respectively) was formed on the polyester film of the obtained laminate.
Glass chrome dry plate (8, 20, 25, 30, 35, 40 μm)] was placed thereon, and the polyester film was peeled off after 15 minutes had elapsed after exposure with the exposure amount obtained above,
% Sodium carbonate aqueous solution for twice as long as the break point for development to dissolve and remove the unexposed portion to form a line pattern, and the substrate on which the pattern is formed is removed with a degreasing agent (Nichigo Morton Co., Ltd. LAC4
1 ”), and after washing with water, electrolytic copper plating having a thickness of 18 μm was applied between the line patterns with a copper sulfate plating solution. Thereafter, a 2.5% aqueous sodium hydroxide solution at 50 ° C. was sprayed for 120 seconds to evaluate the resist releasability (peeling time, residue) when the resist cured portion was peeled off.

(Plating Mole) In the evaluation of the resist releasability, the plating maze having a pattern of line / space = 14 μm / 14 μm was visually observed with a magnifying microscope and evaluated according to the following criteria. ◎ ・ ・ ・ No chipping ○ ・ ・ ・ Staining (discoloration of the substrate due to plating) △ ・ ・ ・ Partially chipping ×× Many plating chips

(Coating around plating) After the resist was peeled off as described above, the cross section of the plating pattern was visually observed with a magnifying microscope, and the surrounding plating was evaluated according to the following criteria. A: It was a rectangle. ○: A part of the corner was rounded. △: All corners were rounded. × ... All corners were rounded and jagged.

Further, the flexibility of the cured resist was evaluated as follows using the above dry film separately. (Cured resist flexibility) A dry film having a resist thickness of 25 μm was laminated with a polyester film having a thickness of 16 μm as a protective film at a temperature of 110 ° C., a roll pressure of 4 kg / cm ² , and a laminating speed of 1.2 m / min. It was cut out into a size of 20 mm × 200 mm and exposed with an exposure amount when the number of steps of the step tablet was 7. Thereafter, the polyester film on both sides of this film was peeled off, and the operation of bending the cured resist portion at 180 degrees was repeated, and the number of times when the cured resist was cracked was examined and evaluated as follows. ◎ ・ ・ ・ 10 times or more ○ ・ ・ ・ 6-9 times △ ・ ・ ・ 2-5 times × ・ ・ ・ 1 time

[Table 2] Sensitivity, Resolving power, Adhesion property, Developer resistance (mJ) (μm) (μm) (μm) Example 1 75 12 10 12 12 〃 2 70 10 8 10 10 〃 3 65 10 8 12 12 〃 4 75 10 10 14 〃 5 70 8 8 10 Comparative Example 1 60 8 10 10 〃 2 65 19 19 24 24 〃 3 69 20 20 30 30 〃 4 75 8 10 10 10 〃 5 150 16 16 16 18

[0073] Table 3 resist peelable plating Mekkitsuki cured resist stripping time residue submerged around flexibility (in seconds) Example 1 34 No ◎ ◎ ◎ 〃 2 33 No ◎ ◎ ◎ 〃 3 32 No ◎ ◎ ◎ 〃 4 27 No ◎ ◎ ◎ 〃 5 31 No ◎ ◎ ○ Comparative Example 1> 120 Yes * 1 * 1 △ 〃 2 26 No * 2 * 2 ◎ 〃 3 24 No * 2 * 2 ○ 〃 4> 120 Yes * 1 * 1 ○ 〃 5 110 Yes ◎ ◎ △ * 1: Not evaluated because of poor resist releasability * 2: Not evaluated because of poor resolution.

[0074]

The photosensitive resin composition and the dry film obtained in the present invention are excellent in sensitivity, resolution, fine line adhesion, developer resistance, plating characteristics, resist flexibility, and resist peelability, and It is useful as an etching resist or plating resist used for manufacturing printed wiring boards for packages, manufacturing lead frames, and precision metal processing.

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI Theme Coat (Reference) G03F 7/004 512 G03F 7/004 512 7/027 502 7/027 502 7/029 7/029 7/031 7/031 7/033 7/033 7/11 501 501 7/11 501 F term (reference) 2H025 AA01 AA02 AA04 AA14 AB11 AB15 AB17 AC01 AD01 BC14 BC32 BC42 BC53 BC81 BC92 CA01 CA28 CB13 CB14 CB43 CB51 DA01 FA03 FA17 4J002 AA06W AA07 BG03W BG04W BG05W BG06W BG07W BG07X BG08W BG12W EE036 EE046 EE056 EH077 ER007 ET007 EU056 EU116 EU176 EU186 EV066 EV216 EV306 EW016 GP03 4J011 AA05 PA69 QA03 QA04 QA12 QA13 QA24 QB03 RA03 SA01 SA21 SA31 SA41 SA62 SA63 SA64 SA82 SA83 SA84 4J027 AA02 AC03 AC06 AC09 AJ09 BA08 BA13 BA14 BA16 BA19 BA21 BA23 BA24 BA26 BA27 CD10

Claims (6)

[Claims] 1. (a) Carboxy containing no unsaturated group
Ru group-containing polymer, (b) represented by the following general formula (1)
Unsaturation of compounds reacted with carboxyl-containing polymers
A functional polymer having a group number of 0.3 to 3.5 mmol / g,
(C) ethylenically unsaturated compound, (d) photopolymerization initiator
A photosensitive resin composition containing. [Chemical 1] [Where R₁Is hydrogen or a methyl group, R₂Is-[(CO)_x
CHX₁(CHX₂)_yO] _z-(Where x is 0 or 1, y
Is an integer of 0-9, z is an integer of 1-10, X₁, X₂Is hydrogen
Or methyl group), R₃2 diisocyanates
Indicates an organic residue excluding the cyanate group] 2. The weight average molecular weight of the carboxyl group-containing polymer (a) which does not contain an unsaturated group is 15,000 to 80.
000 and an acid value of 100 to 240 mg KOH / g, The photosensitive resin composition according to claim 1. 3. (b) A carboxyl-containing polymer obtained by reacting a compound represented by the general formula (1) with an unsaturated group of 0.
The weight average molecular weight of the functional polymer of 3 to 3.5 mmol / g is 6500 to 60000, and the acid value is 30 to 16
It is 0 mgKOH / g, The photosensitive resin composition of Claim 1 or 2 characterized by the above-mentioned. 4. The photosensitive resin composition according to claim 1, wherein the ethylenically unsaturated compound (c) contains an acrylic compound having a urethane bond. 5. The photosensitive resin composition according to claim 1, wherein (d) the photopolymerization initiator contains a hexaarylbiimidazole compound. 6. A dry film comprising a support and the photosensitive resin composition according to any one of claims 1 to 5 layered thereon, and a protective film coated on the support.