JP2002138140A - Polyester resin and photosensitive resin composition using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition having excellent developing ability and photosensitivity, and the obtained cured product of which having excellent adhesiveness, pencil hardness, solvent resistance, acid resistance, heat resistance, gilding resistance, flexibility and the like. SOLUTION: This polyester resin is obtained by reacting (A) a siloxane compound (a) having at least two hydroxyl groups in a molecule, with (B) a reaction product (d) of an epoxy compound (b) having at least two epoxy groups in a molecule with a monocarboxylic acid (c) having at least one photo- crosslinkable group in a molecule, and (C) a polybasic acid anhydride (e) having at least two acid anhydride groups in a molecule. This photosensitive resin composition comprises the polyester resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester resin, a photosensitive resin composition using the same, and a cured product thereof, and more particularly to heat resistance and flexibility which are useful for manufacturing printed circuit boards and can be developed with an aqueous alkali solution. The present invention relates to a liquid solder resist composition excellent in water resistance.

[0002]

2. Description of the Related Art In the printed circuit board manufacturing industry, a solder resist is widely used as a permanent protective film for a printed circuit board. The solder resist is used for the purpose of preventing a solder bridge at the time of soldering, preventing corrosion of a conductor portion at the time of use, maintaining electrical insulation, and the like. Conventionally, a method of forming a solder resist by screen printing using a thermosetting ink or a photocurable ink has been widely used. However, when this method is used, bleeding, bleeding, sagging, and the like at the time of printing reduce the accuracy of the obtained resist pattern, and can respond to recent miniaturization, high density, and high functionality of printed circuit boards. It's gone.

In order to cope with such a printed circuit board, many photo-curable liquid solder resists have been developed, and 50% or more are currently introduced. Among them, those which can be developed with an alkaline aqueous solution have attracted attention, and are characterized by containing a resin having a carboxyl group for dissolving in an alkaline aqueous solution and an ethylenically unsaturated group for imparting photocurability as an essential component. . For example, Japanese Patent Application Laid-Open
No. 62375, JP-A-3-253093 and JP-B-1-54390 disclose phenolic or o-
A resist composition using a resin obtained by reacting a cresolic novolak type epoxy resin with an unsaturated monobasic acid and further reacting a saturated or unsaturated polybasic acid anhydride is disclosed. JP-A-3-289656 discloses that glycidyl (meth) acrylate and the like are copolymerized as constituents,
A composition using a resin in which an epoxy group is modified in the same manner as the above-mentioned resin is disclosed in JP-A-2-97513, and an epoxy compound of a condensate of a phenol and an aromatic aldehyde having a phenolic hydroxyl group ( A composition using an ethylenically unsaturated group-containing polycarboxylic acid resin obtained by reacting a reaction product of (meth) acrylic acid with a polybasic carboxylic acid or an anhydride thereof is disclosed.

[0004]

However, when these compositions are used, for example, as a resin composition for a solder resist, sensitivity, resolution, heat resistance, chemical resistance, gold plating resistance, electrolytic corrosion resistance, etc. Can handle,
The obtained cured film has insufficient flexibility and impact resistance, and there is a problem that cracks occur on the surface of the cured product when a thinned substrate is used.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems. As a result, they have shown high sensitivity and high resolution, and can be developed with a dilute alkaline aqueous solution. The printed circuit board also has excellent solder heat resistance, chemical resistance, gold plating resistance, electrolytic corrosion resistance, etc., does not crack on the cured product surface, and does not warp even when a thinned substrate is used. A photosensitive resin composition for use as well as a cured product have been found. That is, the present invention

(1) The following components (a), (b) and (c)
(A) a siloxane compound having at least two hydroxyl groups in the molecule (a), and (b) a polyester resin having at least two epoxy groups in the molecule. A reaction product (d) of an epoxy compound (b) and a monocarboxylic acid (c) having at least one photocrosslinkable group in the molecule, and (c) at least two acid anhydride groups in the molecule. A polybasic acid anhydride (e). (2) The polyester resin (A) according to (1), wherein the siloxane compound (a) is a compound represented by the following formula:

[0007]

Embedded image (Wherein, R ₁ and R ₂ each independently represent a C ₁ -C ₅ alkylene group; R ₃ represents a C ₁ -C ₅ alkyl group;
n represents an integer of 1 to 150. )

(3) An epoxy compound (b) having at least two epoxy groups in the molecule is bisphenol-
The polyester resin according to (1) or (2), which is an epoxy compound selected from diglycidyl ether of A, diglycidyl ether of bisphenol-F, diglycidyl ether of bisphenol-S, and diglycidyl ether of biphenol. (A), (4) a monocarboxylic acid (c) having at least one or more photocrosslinkable groups in the molecule is acrylic acid, methacrylic acid, cinnamic acid,
Or the polyester resin (A) according to any one of (1) to (3), which is a monocarboxylic acid selected from azidobenzoic acid, and (5) at least two acid anhydride groups in a molecule. (E) is pyromellitic anhydride, 2,3,3 ′, 4′-biphenyltetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride. Anhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,3,3 ′, 4 ′
-Diphenyl ether tetracarboxylic dianhydride, 2,
2 ′, 3,3′-diphenylethertetracarboxylic dianhydride, 3,3 ′, 4,4′-diphenylethertetracarboxylic dianhydride, 2,3,3 ′, 4′-diphenylsulfonetetracarboxylic dianhydride Anhydride, 2,
2 ', 3,3'-diphenylsulfonetetracarboxylic dianhydride, 3,3', 4,4'-diphenylsulfonetetracarboxylic dianhydride, 2,3,3 ', 4'-benzophenonetetracarboxylic acid Dianhydride, 2,2 ',
3,3′-benzophenonetetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 2,3,3 ′, 4′-diphenylmethanetetracarboxylic dianhydride, , 2 ', 3,3'-
Diphenylmethanetetracarboxylic dianhydride, 3,
The polybasic acid anhydride selected from 3 ', 4,4-diphenylmethanetetracarboxylic dianhydride and ethylene glycol ditrimellitate dianhydride according to any one of (1) to (4). Polyester resin (A) and (6) polyester resin (A) having an acid value of 50 to 150 mg. The polyester resin (A) according to any one of (1) to (5), which is in the range of KOH / g, and the polyester resin (7) according to any one of (1) to (6). A photosensitive resin composition comprising a polyester resin (A), a cross-linking agent (B), a photopolymerization initiator (C) and a thermosetting component (D). Another object of the present invention is to provide a cured product of a conductive resin composition, and a printed board having a cured product layer according to (9) or (8).

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester resin of the present invention is characterized by being obtained by reacting the following components (a), (b) and (c). (A) a siloxane compound (a) having at least two hydroxyl groups in the molecule, and (b) an epoxy compound (b) having at least two epoxy groups in the molecule and at least one photocrosslinkable compound in the molecule. A reaction product (d) with a monocarboxylic acid (c) having a group,
(C) Polybasic acid anhydride (e) having at least two acid anhydride groups in the molecule.

As the siloxane compound (a) used for producing the polyester resin of the present invention, any compound having at least two hydroxyl groups in the molecule can be used. A siloxane compound (a) having a structure is particularly preferred.

In the formula (1), R ₁ and R ₂ are each independently
Although a C ₁ -C ₅ alkylene group is shown, a C ₁ -C ₃ alkylene group is particularly preferred in terms of heat resistance, flexibility and the like. When these alkylene groups exceed C ₅ , heat resistance is lowered, and when used as a composition, tackiness may be exhibited, which is not preferable. R ₃ in the formula (1) is C ₁
Represents an alkyl group -C _5, heat resistance, when the viewpoint of flexibility of the alkyl group, especially preferably a methyl group or an ethyl group. If the alkyl group is as Kosu the C _5, the heat resistance is lowered, when used as a composition, because it may have tackiness is not preferred.

Further, n representing a repeating unit in the formula (1)
Represents an integer of 1 to 150, but has heat resistance, flexibility, and developability when used as a photosensitive resin composition,
From the viewpoint of sensitivity and the like, n is particularly preferably 5 to 100. If n is 0, it becomes inflexible and conversely n
Exceeds 150, the sensitivity and developability of the photosensitive resin composition are undesirably reduced.

These siloxane compounds (a) having at least two hydroxyl groups in the molecule are, for example, available from Chisso Corporation under the trade names Cylaprene FM-4411, FM
-4421 and FM-4425.

As the epoxy compound (b) used for producing the polyester resin of the present invention, any epoxy compound having at least two epoxy groups in the molecule can be used, but bisphenol-A
And those having a skeleton of diglycidyl ether of bisphenol-F, diglycidyl ether of bisphenol-S, or diglycidyl ether of biphenol.

As the bisphenol type epoxy resin,
For example, Epicoat 828, Epicoat 1001 (manufactured by Yuka Shell Epoxy), UVR-6410 (manufactured by Union Carbide), D.C. E. FIG. Bisphenol A type epoxy resin such as R-331 (manufactured by Dow Chemical Company), YD-8125 (manufactured by Toto Kasei), bisphenol such as UVR-6490 (manufactured by Union Carbide), YDF-8170 (manufactured by Toto Kasei) -F type epoxy resin, bis (4-glycidyloxyphenyl) sulfone (manufactured by Yorkshire Chemicals) bisphenol-S type epoxy resin, and the like.

Examples of the biphenol type epoxy resin include a bixylenol type epoxy resin of YX-4000 (manufactured by Yuka Shell Epoxy Co., Ltd.) and YL-6121 (manufactured by Yuka Shell Epoxy Co., Ltd.).

As the monocarboxylic acid (c) used for producing the polyester resin of the present invention, a monocarboxylic acid (c) having at least one photocrosslinkable group in a molecule is preferably used. The term "photocrosslinking property" as used herein refers to a functional group having a property capable of causing a crosslinking reaction when irradiated with energy rays such as infrared rays, visible rays, ultraviolet rays, X-rays, and electron beams. The functional group includes, for example, an ethylenically unsaturated group, an azide group and the like. In order for the photosensitive resin composition of the present invention to have effective photosensitivity having these functional groups, the monocarboxylic acid (c) may be selected from the group consisting of acrylic acid, methacrylic acid, cinnamic acid, and azidobenzoic acid. Monocarboxylic acids selected from among them are particularly preferred.

The polybasic acid anhydride (e) used for producing the polyester resin of the present invention may be any polybasic acid anhydride (e) having at least two acid anhydride groups in the molecule. Although it can be used, in order for the photosensitive resin composition of the present invention to have effective photosensitivity and maintain developability, pyromellitic anhydride, 2,3,3 ', 4'
-Biphenyltetracarboxylic dianhydride, 2,2 ',
3,3'-biphenyltetracarboxylic dianhydride, 3,
3 ', 4,4'-biphenyltetracarboxylic dianhydride, 2,3,3', 4'-diphenylethertetracarboxylic dianhydride, 2,2 ', 3,3'-diphenylethertetracarboxylic dianhydride Thing, 3,3 ', 4
4'-diphenylethertetracarboxylic dianhydride, 2,3,3 ', 4'-diphenylsulfonetetracarboxylic dianhydride, 2,2', 3,3'-diphenylsulfonetetracarboxylic dianhydride, 3 , 3 ', 4,4'
-Diphenylsulfonetetracarboxylic dianhydride,
2,3,3 ′, 4′-benzophenonetetracarboxylic dianhydride, 2,2 ′, 3,3′-benzophenonetetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid Dianhydride, 2,3,3 ',
4'-diphenylmethanetetracarboxylic dianhydride,
Many selected from 2,2 ', 3,3'-diphenylmethanetetracarboxylic dianhydride, 3,3', 4,4-diphenylmethanetetracarboxylic dianhydride and ethylene glycol ditrimellitate dianhydride Basic anhydrides are particularly preferred.

The polyester resin (A) of the present invention can be produced, for example, as follows. First, the reaction between the epoxy resin (b) and the monocarboxylic acid (c) is carried out by using no solvent or a solvent having no alcoholic hydroxyl group, for example, ketones such as acetone, ethyl methyl ketone and cyclohexanone, and benzene. , Toluene, xylene, aromatic hydrocarbons such as tetramethylbenzene, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether,
Glycol ethers such as triethylene glycol dimethyl ether and triethylene glycol diethyl ether, ethyl acetate, butyl acetate, methyl cellosolve acetate, ethyl cellosolve acetate, butyl cellosolve acetate, carbitol acetate, propylene glycol monomethyl ether acetate, dialkyl glutarate, dialkyl succinate , Esters such as dialkyl adipates, cyclic esters such as γ-butyrolactone, petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha,
The reaction is performed in a single or mixed organic solvent such as a petroleum-based solvent such as solvent naphtha.

At the time of the reaction, a catalyst is preferably used to promote the reaction, and the amount of the catalyst is usually 0.1 to 10% by weight based on the reaction raw material mixture. The reaction temperature at that time is usually 60 to 150 ° C., and the reaction time is preferably 5 to 60 hours. As a catalyst used in this reaction, for example, triethylamine, benzyldimethylamine, triethylammonium chloride,
Examples include benzyltrimethylammonium bromide, benzyltrimethylammonium iodide, triphenylphosphine, triphenylstibine, methyltriphenylstibine, chromium octoate, zirconium octoate and the like.

The reaction product (d) thus obtained is
It is a compound obtained by adding the glycidyl group of the epoxy compound (b) and the carboxyl group of the monocarboxylic acid (c), and simultaneously functions as a diol compound having a photocrosslinkable group because it generates a secondary alcoholic hydroxyl group. be able to.

Next, the reactant (d), the siloxane compound (a) and the polybasic acid anhydride (e) are subjected to an esterification reaction between an acid anhydride group and an alcohol in the above-mentioned solvent to carry out the polyester resin of the present invention ( A) can be obtained. In this reaction, one of the acid anhydride groups is esterified with an alcohol, and the other remains as a carboxyl group.
The reaction temperature at this time is usually 60 to 150 ° C., and the reaction time is preferably 5 to 60 hours. Examples of the catalyst used in this reaction include triethylamine, benzyldimethylamine, triethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide, triphenylphosphine, triphenylstibine, methyltriphenylstibine, chromium octanoate, octane Zirconium acid and the like.

It is preferable that the reactants (d), the siloxane compound (a) and the polybasic acid anhydride (e) are charged so that the terminal of the finally obtained polyester resin is an alcohol. That is, it is desirable that the total equivalent% of the reactant (d) and the siloxane compound (a) exceeds 50% and the equivalent% of the polybasic acid anhydride (e) is less than 50%. The equivalent% of polybasic acid anhydride (e) is 50%
In the above case, an anhydride group remains at the terminal of the polyester resin, and the stability of the photosensitive resin composition using the polyester resin (A) may be impaired.

The amount of the siloxane compound (a) to be charged is 1 to 30% by weight, preferably 2 to 20% by weight, when the solid content of the polyester resin (A) is 100% by weight. preferable. When the amount of the siloxane compound (a) is less than 1% by weight, the heat resistance and flexibility of the photosensitive resin composition using the polyester resin (A) decrease, and when the amount exceeds 30% by weight. It is not preferable because the developing property and the adhesion may be impaired.

Further, the reactants (d), the siloxane compound (a) and the polybasic anhydride (e) are charged in such a manner that the solid resin acid value of the obtained polyester resin (A) is 50 to 150.
mg. It is important to calculate and feed so as to be in the range of KOH / g. The acid value of this solid was 50 mg. KOH /
When the amount is less than g, the developability of the photosensitive resin composition using the polyester resin (A) is remarkably reduced, and in the worst case, development may not be performed. In addition, the solid content acid value is 15
0 mg. If it exceeds KOH / g, the developability is too high and the photocurable pattern may be washed away, which is not preferable.

The photosensitive resin composition of the present invention is characterized by containing the polyester resin (A), the crosslinking agent (B), the photopolymerization initiator (C) and the thermosetting component (D).

The crosslinking agent (B) used in the photosensitive resin composition of the present invention includes (meth) acrylate compounds, azide compounds, diazo compounds, nitro compounds and the like. (Meth) acrylate compounds which can be radically polymerized by C) and can easily undergo a crosslinking reaction with the polyester resin (A) are particularly preferred.
Examples of the (meth) acrylate compound include 2-hydroxyethyl (meth) acrylate, phenoxyethyl (meth) acrylate, acryloyl monophorin, isobornyl (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and nonanediol di. (Meth) acrylate, polyethylene glycol di (meth)
Acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetraacrylate, ditrimethylolpropane tetra (meth) acrylate,
Examples include acrylates such as dipentaerythritol poly (meth) acrylate. These can be used alone or in combination.

The amount of the crosslinking agent (B) used in the photosensitive resin composition of the present invention is preferably from 1 to 40% by weight when the total solid content of the photosensitive resin composition is 100% by weight. Particularly preferably, it is 5 to 30% by weight.

The photopolymerization initiator (C) used in the photosensitive resin composition of the present invention includes, for example, acetophenone,
2,2-diethoxy-2-phenylacetophenone, p
-Dimethylaminopropiophenone, dichloroacetophenone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholino Benzophenones such as acetophenones such as phenyl) -butanone-1, benzophenone, p-chlorobenzophenone, p, p-bisdimethylaminobenzophenone, p, p-bisdiethylaminobenzophenone, and 4-benzoyl-4'-methyl-diphenylsulfide Benzoin ethers such as benzyl, benzoin, benzoin methyl ether and benzoin isobutyl ether; ketals such as benzyl dimethyl ketal; thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone and 2-iso Thioxanthones such as propylthioxanthone, anthraquinone, 2,4,5-triarylimidazole dimer, 2,4,6-tris (trichloromethyl) -s-triazine, 2,4,6-trimethylbenzoyldiphenylphosphine oxide And the like. These photopolymerization initiators (C) may be used alone or
More than one species can be used in combination. The amount used is preferably 1 to 30% by weight, particularly preferably 2 to 20% by weight in the composition.

These photopolymerization initiators (C) are N, N-
Dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, N, N-dimethylaminobenzoic acid pentyl ester, 4,4′-bis (N, N-dimethylamino) -benzophenone, 4,
It can be used in combination with a sensitizer such as 4'-bis (N, N-dimethylamino) -benzophenone.
The use amount of the sensitizer is preferably 50% by weight or less based on the photopolymerization initiator (C).

The curing component (D) used in the present invention comprises:
During the heat curing after development, it reacts thermally with the carboxyl groups in the polyester resin (A) to impart alkali resistance, solvent resistance, heat resistance, electrical insulation and gold plating resistance to the cured coating film.

Examples of the curing component (D) include novolak epoxy resins, bisphenol epoxy resins, epoxy resins of polycondensates of phenol and hydroxybenzaldehyde, heterocyclic epoxy resins, and epoxy resins containing a naphthalene skeleton.

Examples of the phenol novolak type epoxy resin include Epiclon N-770 (manufactured by Dainippon Ink and Chemicals, Inc.); E. FIG. N438 (manufactured by Dow Chemical Company), Epicoat 154 (Yukaka Epoxy Co., Ltd.)
And RE-306 (manufactured by Nippon Kayaku Co., Ltd.). Examples of the cresol novolak type epoxy resin include Epicron N-695 (manufactured by Dainippon Ink and Chemicals, Inc.), EOCN-102S, and EOCN-103.
S, EOCN-104S (Nippon Kayaku Co., Ltd.), UVR
-6650 (manufactured by Union Carbide), ESCN-1
95 (manufactured by Sumitomo Chemical Co., Ltd.).

As an epoxy resin of a polycondensate of phenol and hydroxybenzaldehyde, for example, EPPN-
502H, EPPN-503 (all manufactured by Nippon Kayaku),
TACTICX-742 (manufactured by Dow Chemical Company), Epicoat E1032H60 (Yukaka Epoxy Co., Ltd.)
Manufactured).

As the bisphenol type epoxy resin,
For example, Epicoat 828, Epicoat 1001 (manufactured by Yuka Shell Epoxy), UVR-6410 (manufactured by Union Carbide), D.C. E. FIG. Bisphenol A type epoxy resin such as R-331 (manufactured by Dow Chemical Company), YD-8125 (manufactured by Toto Kasei), bisphenol such as UVR-6490 (manufactured by Union Carbide), YDF-8170 (manufactured by Toto Kasei) F-type epoxy resins and the like can be mentioned.

Examples of the heterocyclic epoxy resin include TEPIC (manufactured by Nissan Chemical Industries, Ltd.).

Examples of the naphthalene skeleton-containing epoxy resin include NC-7000 (manufactured by Nippon Kayaku Co., Ltd.) and EXA-
4750 (manufactured by Dainippon Ink and Chemicals, Inc.). As the alicyclic epoxy resin, for example, EHPE-
3150 (manufactured by Daicel Chemical Industries, Ltd.).

These curing components (D) can be used alone or
More than one species can be used in combination. The amount used is preferably from 1 to 50% by weight, particularly preferably from 3 to 45% by weight in the composition.

Further, these curing components (D) include:
In order to further improve properties such as adhesion, chemical resistance, and heat resistance, it is particularly preferable to use an epoxy resin curing (acceleration) agent in combination. The amount of epoxy resin curing (acceleration) agent used is
0.01 to 100 parts by weight of the epoxy compound
The amount is preferably 25 parts by weight, particularly preferably 0.1 to 15 parts by weight. Commercially available products include, for example, C11Z, 2PH
Z, 2MZ-AZINE, 2E4MZ-AZINE, 2
Imidazole and its derivatives such as E4MZ-CN and 2MA-OK (all manufactured by Shikoku Chemical Industry Co., Ltd.), and tertiary amines such as hexa (N-methyl) melamine and 2,4,6-tris (dimethylamino) phenol Compounds, triazine compounds such as benzoguanamine, acetoguanamine and melamine, and acid anhydrides such as 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride And polyamines such as dicyandiamide and organic phosphines such as triphenylphosphine. Of these, melamine and dicyandiamide are preferred.

The photosensitive resin composition of the present invention may further contain, if necessary, barium sulfate, barium titanate, silicon oxide powder, fine powdery oxide for the purpose of improving properties such as heat resistance, adhesion and hardness. Inorganic fillers such as silicon, amorphous silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, and mica powder can be used. The amount used is preferably 60% by weight or less in the composition of the present invention, and particularly preferably 5 to 40% by weight.

Further, if necessary, colorants such as phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, carbon black and naphthalene black, and polymerization inhibition of hydroquinone, hydroquinone monomethyl ether, etc. Agents, thickeners such as asbestos, benton, montmorillonite, etc., adhesion-imparting agents such as silicone-based, fluoropolymer-based antifoaming agents and / or leveling agents, imidazole-based, thiazole-based, triazole-based, silane coupling agents, etc. Additives such as agents can be used.

The photosensitive resin composition of the present invention comprises (A)
The components (B), (C), and (D), and if necessary, the inorganic filler and the other components described above are preferably mixed in the above-described ratio, and uniformly mixed, dissolved, and dispersed by a roll mill or the like. It can be obtained by: In addition, a solvent may be used together if desired, mainly for adjusting the viscosity. This solvent may be a solvent used in the production of the components. Examples of the solvent include ketones such as ethyl methyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene, glycol ethers such as dipropylene glycol dimethyl ether and dipropylene glycol diethyl ether, ethyl acetate, and acetic acid. Esters such as butyl, butyl cellosolve acetate, carbitol acetate, propylene glycol monomethyl ether acetate, petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, solvent naphtha, etc. γ-butyrolactone, N-methyl-2-pyrrolidone, etc. Organic solvents.

When the above-mentioned curing component (D) and a curing accelerator are mixed in advance with a solder resist composition to form a one-pack type, the viscosity tends to increase before application to a circuit board blank. The two-component type is composed of a main agent solution mainly composed of the polyester resin (A) and a curing accelerator and the like, and a curing agent solution mainly composed of the curing component (D) ((B), (C) ) The component is added to one or both of them), and it is preferable to use them in combination at the time of use.

The photosensitive resin composition of the present invention is useful as a resist ink in a liquid state, particularly as a resist ink for a printed circuit board, and is also used as a resin for interlayer insulation of a printed circuit board, a paint, a coating agent, an adhesive and the like. it can.

The cured product of the present invention is obtained by photo-curing the above-mentioned photosensitive resin composition of the present invention by irradiation with energy rays such as ultraviolet rays, and further obtained by further thermosetting the photo-cured cured film. . Curing by irradiation with energy rays such as ultraviolet rays can be performed by a conventional method. When irradiating ultraviolet rays, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, an ultraviolet light emitting laser (for example, an excimer laser)
Or the like may be used. The cured product of the resin composition of the present invention is used for an electric / electronic component such as a printed board having a through hole as a permanent resist, for example.

The printed board of the present invention has a cured product layer of the above resin composition. The thickness of this cured product layer is 5 to 16
It is about 0 μm, preferably about 10 to 60 μm. The printed circuit board can be obtained, for example, as follows. That is, when a liquid resin composition is used, the printed wiring board is usually coated with a film having a thickness of 5 to 160 μm by a method such as a screen printing method, a spray method, a roll coating method, an electrostatic coating method, and a curtain coating method. After applying the composition of the present invention and drying the coating film usually at 60 to 110 ° C., the negative film is brought into direct contact with the coating film (or placed on the coating film in a non-contact state) and irradiated with ultraviolet light. The exposed portion is developed using a diluted alkaline aqueous solution described later, for example, by spraying, rocking immersion, brushing, scrubbing, or the like. Then, if necessary, irradiate ultraviolet rays, then usually 100 to 200
By performing the heat treatment at ℃, a printed circuit board having a permanent protective film satisfying various characteristics can be obtained.

Examples of the developing solution include sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate,
Aqueous solutions of inorganic salts such as sodium bicarbonate, potassium bicarbonate, sodium metasilicate and potassium metasilicate, organic amine aqueous solutions such as trimethylamine, triethylamine, monomethanolamine, diethanolamine and triethanolamine, tetramethylammonium hydroxide, Examples include ammonium hydroxide such as tetraethylammonium hydroxide. These can be used alone or in combination of two or more. The temperature is 15
It can be arbitrarily adjusted between -45 ° C. A small amount of a surfactant, an antifoaming agent or the like may be mixed in this developer.

[0048]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples, but it should not be construed that the invention is limited thereto.

Example 1 (Synthesis of Polyester Resin (A)) In a 1 L four-necked flask, Epicoat 828 (trade name: Yuka Shell Epoxy) was used as an epoxy compound (b) having at least two epoxy groups in the molecule. Bisphenol-A type epoxy resin Epoxy equivalent: 185.9 g
/ Equivalent, molecular weight 371.8) in 210.2 g (0.5
Acrylic acid as a monocarboxylic acid (c) having at least one or more photocrosslinkable groups in the molecule.
1.4 g (1.13 equivalents), 0.30 g of hydroquinone monomethyl ether as a thermal polymerization inhibitor, 1.05 g of triphenylphosphine as a reaction catalyst, and 9
The reaction was performed at a temperature of 8 ° C. for 24 hours. The acid value after the reaction is
It was 0.2 mg · KOH / g. After cooling to 60 ° C., the reaction product (molecular weight as diol compound: 516,
The reaction product was 0.565 equivalent), 280.6 g of triethylene glycol dimethyl ether as a solvent,
As a siloxane compound (a) having at least two hydroxyl groups in a molecule, 42.1 of Silaace FM-4411 (trade name: terminal hydroxyl group siloxane compound manufactured by Chisso, hydroxyl equivalent: 603 g / equivalent, molecular weight: 1206) was 42.1.
g (0.035 equivalent) and 0.35 g of 2-methylhydroquinone as a thermal polymerization inhibitor were added and stirred to make the solution uniform. The solution then contains at least 2
87.2 g (0.4%) of pyromellitic anhydride (manufactured by Nippon Shokubai) as a polybasic anhydride (e) having two acid anhydride groups.
(00 equivalent) and reacted at a temperature of 95 ° C. for 7 hours to obtain a solution containing the polyester resin (A) of the present invention (this solution is referred to as A-1). The solution acid value after the reaction was 65 mg.
KOH / g (concentration: about 60%, solid acid value: 1
08 mg KOH / g). Initial theoretical acid value is 128mg
-KOH / g, indicating that the reaction was almost complete.

Example 2 Comparative Example 1 Each component was blended according to the blending composition shown in Table 1 (the numerical values are parts by weight) and kneaded with a three-roll mill to prepare a photosensitive resin composition of the present invention. This was screen-printed using a 100-mesh screen at 15 to 25 μm.
The entire surface is coated on a copper-clad polyimide substrate (thickness: about 0.2 mm) which is patterned to have a thickness of m, and the coating film is dried with a hot air drier at 80 ° C. for 40 minutes. The dried membrane was rubbed with absorbent cotton and evaluated for tackiness.
Next, a negative film having a resist pattern was brought into close contact with the coating film, and irradiated with ultraviolet rays (exposure amount: 200 mJ / cm ² ) using an ultraviolet exposure apparatus (Oak Seisakusho Co., Ltd., model HMW-680GW). Next, development was performed with a 1% aqueous solution of sodium carbonate for 60 seconds at a spray pressure of 2.0 kg / cm ² to remove and remove unexposed portions. The obtained product was evaluated for developability, resolution, photosensitivity, and surface gloss as described below. Then, the hot air dryer at 150 ° C.
The test piece having the cured film obtained was subjected to a test for substrate warpage, adhesion, pencil hardness, solvent resistance, acid resistance, heat resistance, and gold plating resistance as described below. Table 2 shows the results. In addition, the test method and the evaluation method are as follows.

(Tackiness) The following evaluation criteria were used.・: There was no tack and there was no lint of absorbent cotton. Δ: There was a small amount of tack, and lint of absorbent cotton remained. ×: The tack was remarkable, and absorbent cotton was stuck.

(Developability) The following evaluation criteria were used.・: At the time of development, the ink was completely removed and development was possible. ×: Some parts are not developed during development.

(Resolution) A 50 μm negative pattern is adhered to the dried coating film, and the coating film is irradiated with ultraviolet rays having an integrated light amount of 200 mJ / cm 2. Then, the film is developed with a 1% aqueous solution of sodium carbonate for 60 seconds at a spray pressure of 2.0 kg / cm @ 2, and the transfer pattern is observed with a microscope. The following criteria were used:・: The pattern edge is a straight line and is resolved. X: Peeling or pattern edges are jagged.

(Photosensitivity) A step tablet (manufactured by Kodak Co., Ltd.) was brought into close contact with the dried coating film, and the integrated light amount was 50
Irradiation exposure with ultraviolet rays of 0 mJ / cm ² is performed. Next, the film is developed with a 1% aqueous solution of sodium carbonate for 60 seconds at a spray pressure of 2.0 kg / cm ² , and the number of steps of the coating film left undeveloped is confirmed. The following criteria were used: ○ ・ ・ ・ ・ ・ ・ 8 steps or more × ・ ・ ・ ・ 7 steps or less

(Surface Gloss) The dried coating film was coated with 200 mJ
/ Cm ² UV irradiation. Next, it is developed with a 1% aqueous solution of sodium carbonate for 60 seconds at a spray pressure of 2.0 kg / cm ² 2, and the cured film after drying is observed. The following criteria were used: ○ ・ ・ ・ ・ No fogging observed ×× ・ ・ ・ Slight fogging observed

(Substrate Warpage) The following criteria were used. ○ ·························· The board has warpage

(Adhesion) According to JIS K5400,
100 test pieces were made with 1 mm-thick squares, and a peeling test was performed using Cellotape (registered trademark). The state of peeling was evaluated by the following criteria. 〇 ・ ・ ・ ・ ・ ・ No peeling × ・ ・ ・ ・ ・ ・ Peel off

(Pencil hardness) Evaluation was performed according to JIS K5400.

(Solvent Resistance) A test piece is immersed in isopropyl alcohol at room temperature for 30 minutes. After confirming that there was no abnormality in the appearance, a peeling test was carried out using cellophane tape and evaluated according to the following criteria. ○ ・ ・ ・ ・ ・ ・ No abnormality in the appearance of the coating film and no blistering or peeling × ・ ・ ・ ・ Pattern with blistering or peeling

(Acid Resistance) A test piece is immersed in a 10% aqueous hydrochloric acid solution at room temperature for 30 minutes. After confirming that there is no abnormality in the appearance,
A peeling test was performed using cellotape and evaluated according to the following criteria. ○ ・ ・ ・ ・ ・ ・ No abnormality in the appearance of the coating film and no blistering or peeling × ・ ・ ・ ・ Body with blistering or peeling

(Heat resistance) A rosin-based flux was applied to a test piece and immersed in a solder bath at 260 ° C. for 5 seconds. This was defined as one cycle, and three cycles were repeated. After allowing to cool to room temperature, a peeling test was performed using cellophane tape, and evaluated according to the following criteria. 〇: No abnormalities in the appearance of the coating film and no blistering or peeling ×: ・ ・ ・ Films with blistering or peeling

(Gold Plating Resistance) A test substrate was treated with an acidic degreasing solution (Mexex L-5, manufactured by McDermitt Japan) at 30 ° C.
B in a 20 vol% aqueous solution), washed with water, then immersed in a 14.4 wt% aqueous ammonium persulfate solution at room temperature for 3 minutes, washed with water, and further placed in a 10 vol% aqueous sulfuric acid solution at room temperature for 1 minute. After immersion for a minute, it was washed with water.
Next, this substrate was immersed in a 30 ° C. catalyst solution (manufactured by Meltex, a 10 vol% aqueous solution of a metal plate activator 350) for 7 minutes, washed with water, and washed at 85 ° C. with a nickel plating solution (manufactured by Meltex, Melplate Ni-). 865M 2
After immersing in a 0 vol% aqueous solution (pH 4.6) for 20 minutes and performing nickel plating, the substrate was immersed in a 10 vol% aqueous sulfuric acid solution at room temperature for 1 minute and washed with water. Next, the test substrate is
Immersion for 10 minutes in a gold plating solution (available from Meltex, 15 vol% of Aurolectroles UP and 3 vol% of gold potassium cyanide, pH 6), electroless gold plating, washing with water, and further heating with 60 ° C. warm water. Dipped for minutes, washed with water and dried. A cellophane adhesive tape was adhered to the obtained electroless gold-plated evaluation substrate, and the state when peeled off was observed. ：: No abnormality at all. X: Some peeling was observed.

(Flexibility) A test film was formed on a polyimide film having a thickness of 200 μm, and after bending at 180 °, the surface was observed. ○: No crack ×: Crack

[0064]

Note 1 Epoxy acrylate tetrahydrophthalic anhydride adduct of reaction product of bisphenol-F type epoxy resin manufactured by Nippon Kayaku and epichlorohydrin, solid content concentration:
65% 2 Caprolactone-modified dipentaerythritol hexaacrylate manufactured by Nippon Kayaku 3 2-Methyl- (4- (methylthio) phenyl) -2-morpholino-1-propane manufactured by Ciba Geigy 4 2,4-diethyl manufactured by Nippon Kayaku Thioxanthone 5 Nippon Kayaku's biphenyl skeleton polyfunctional epoxy resin 6 Big Chemie's leveling agent 7 Big Chemie's antifoaming agent

[0066]

As is clear from the results in Table 2, the photosensitive resin composition using the polyester resin (A) of the present invention has high sensitivity and high resolution, and can be developed with a dilute aqueous alkaline solution. The cured film is also excellent in solder heat resistance, chemical resistance, gold plating resistance, flexibility, etc. There is no crack on the surface of the cured product, and there is no warping on the substrate even when using a thinned substrate It is clear that this is a photosensitive resin composition for a substrate.

[0068]

The photosensitive resin composition using the polyester resin (A) of the present invention is selectively exposed to ultraviolet rays through a film on which a pattern is formed, and is developed by developing an unexposed portion. In the formation of, the developability, excellent in photosensitivity, the obtained cured product, adhesiveness, pencil hardness, solvent resistance, acid resistance, heat resistance, those that sufficiently satisfy gold plating resistance, etc., Suitable for liquid solder resist ink composition for printed wiring boards.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03F 7/027 512 G03F 7/027 512 5E314 515 515 7/075 511 7/075 511 H05K 3/28 H05K 3 / 28 DF term (reference) 2H025 AA01 AA02 AA04 AA06 AA07 AA08 AA10 AA13 AB15 AC01 AD01 BC13 BC42 BC64 BC74 BC78 BC83 BC85 BC86 BH04 BJ10 CA00 CC17 4J002 CD002 CD022 CD032 CD052 CD062 CF241 CF261 ED08737 EV0 EF0137EV0 EW147 FD147 FD206 GP03 4J011 AA05 BA03 QA03 QA12 QA22 QB14 QC07 RA10 SA01 SA21 SA41 SA51 SA63 SA64 SA82 UA01 VA01 WA01 XA02 4J027 AB01 AB10 AB18 AB26 AB29 BA07 BA19 BA23 BA25 BA27 CA10 CB10 CC02 AB05 AD10 GA42 GA43 HA01 HA05 HB06 JB182 JE152 JE222 KA02 5E314 AA25 AA27 AA34 C C07 DD07 FF06 GG11 GG14

Claims (9)

[Claims] 1. A polyester resin (A) obtained by reacting the following components (a), (b) and (c). (A) a siloxane compound (a) having at least two hydroxyl groups in the molecule, and (b) an epoxy compound (b) having at least two epoxy groups in the molecule and at least one photocrosslinkable compound in the molecule. (D) a reaction product with a monocarboxylic acid having a group (c); and (c) a polybasic acid anhydride having at least two acid anhydride groups in the molecule (e). 2. The siloxane compound (a) has the following formula (1)
The polyester resin (A) according to claim 1, which is a compound represented by the formula: Embedded image (Wherein, R ₁ and R ₂ each independently represent a C ₁ -C ₅ alkylene group; R ₃ represents a C ₁ -C ₅ alkyl group;
n represents an integer of 1 to 150. ) 3. An epoxy compound (b) having at least two epoxy groups in the molecule, wherein the diglycidyl ether of bisphenol-A, the diglycidyl ether of bisphenol-F, the diglycidyl ether of bisphenol-S, or the diglycidyl ether of bisphenol-S. The polyester resin (A) according to claim 1 or 2, which is an epoxy compound selected from diglycidyl ethers. 4. The monocarboxylic acid (c) having at least one photocrosslinkable group in the molecule is selected from acrylic acid, methacrylic acid, cinnamic acid and azidobenzoic acid. The polyester resin (A) according to any one of claims 1 to 3, wherein 5. A polybasic acid anhydride (e) having at least two acid anhydride groups in a molecule thereof, comprising pyromellitic anhydride,
2,3,3 ', 4'-biphenyltetracarboxylic dianhydride, 2,2', 3,3'-biphenyltetracarboxylic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic acid Dianhydride, 2,3,3 ', 4'-diphenylethertetracarboxylic dianhydride, 2,2', 3,3 '
-Diphenyl ether tetracarboxylic dianhydride,
3,3 ′, 4,4′-diphenylethertetracarboxylic dianhydride, 2,3,3 ′, 4′-diphenylsulfonetetracarboxylic dianhydride, 2,2 ′, 3,3′-
Diphenylsulfonetetracarboxylic dianhydride, 3,
3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride, 2,3,3 ′, 4′-benzophenonetetracarboxylic dianhydride, 2,2 ′, 3,3′-benzophenonetetracarboxylic dianhydride Anhydrous, 3,3 ', 4
4′-benzophenonetetracarboxylic dianhydride,
2,3,3 ', 4'-diphenylmethanetetracarboxylic dianhydride, 2,2', 3,3'-diphenylmethanetetracarboxylic dianhydride, 3,3 ', 4,4-diphenylmethanetetracarboxylic dianhydride The polyester resin (A) according to any one of claims 1 to 4, which is a polybasic acid anhydride selected from anhydrides and ethylene glycol ditrimellitate dianhydrides. 6. The polyester resin (A) having a solid content acid value of:
50-150 mg. The polyester resin (A) according to any one of claims 1 to 5, which is in a range of KOH / g. 7. A composition comprising the polyester resin (A) according to claim 1, a crosslinking agent (B), a photopolymerization initiator (C) and a thermosetting component (D). Characteristic photosensitive resin composition. 8. A cured product of the photosensitive resin composition according to claim 7. 9. A printed circuit board having the cured product layer according to claim 8.