JPH10133373A - Resin composition, permanent resist resin composition and hardened material thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition high in resolution, capable of being developed with aq. dil. alkali solution and improved in solvent resistance, plating resistance and heat resistance by incorporating a specific epoxy group-containing polycarboxylate resin, a photocationic polymerization initiator and a diluent into the composition. SOLUTION: The epoxy group-containing polycarboxylate resin (A), the photocatoinic polymerization initiatior (B) and the diligent (C) are incorporated. The epoxy group-containing polycarboxylate resin (A) is a reaction product of a copolymerizable epoxy resin (d) with a polybasic acid anhydride (e) and the copolymerization type epoxy resin (d) is a reaction product of a monoethylenic unsaturated group-containing epoxy compound (a) with a hydroxide-containing monoethylenic unsaturated compound (b) and a monoethylenic unsaturated compound (c) except the component (a) and the component (b). In this case, as the monomethylenic unsaturated group-containing epoxy resin, glycidyl (metha)acrylate, glycidyl vinyl ether or the like is exeplified. Also, as the hydroxide-containing monethylenic unsaturated compound, 2-hydroxyethyl (metha)acrylate or the like is exemplified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin composition useful as a permanent resist for a printed wiring board, and a cured product thereof.

[0002]

2. Description of the Related Art Conventionally, printed wiring boards have been manufactured using a copper-clad laminate and by a subtractive method of removing unnecessary portions of the copper foil circuit by etching. It is difficult to form high-density wiring boards, and it also has drawbacks such as small diameter through holes and via holes that cannot be uniformly formed by electroplating. That is the current situation.

On the other hand, recently, a full additive method of forming an adhesive layer on a laminate made of an insulating base material and forming a circuit and a through hole by electroless plating has attracted attention. In this method, the conductor pattern accuracy is determined only by the transfer accuracy of the plating resist, and since the conductor portion is formed only by electroless plating, even with a substrate having a high aspect ratio through hole, uniform through hole plating with high throwing power can be achieved. It is possible to do. Until now, the additive method has been considered suitable for general consumer use, but it has begun to be used as an industrial, high-density, high-multilayer substrate manufacturing process.

[0004]

Generally, in an additive method for manufacturing a substrate for consumer use, a plating resist pattern is transferred by a screen printing method. However, in order to manufacture a printed wiring board having high-density wiring, ,
It is necessary to form a plating resist pattern by photolithography, that is, to employ a photoadditive method using a photoresist. Photoresists suitable for photo-additive methods include sensitivity, resolution,
In addition to the inherent properties of photoresist such as developability, the following properties are required. Development is limited to 1,1,1-trichloroethane-based organic solvent or alkaline aqueous solution, so that it can be developed by any of them, it can withstand electroless plating performed for a long time under high temperature and high alkaline conditions, plating After processing, have excellent solder resist properties as permanent resist, 260 in soldering process
It must have heat resistance to withstand temperatures of about ° C and a solvent resistance to organic solvents for cleaning flux used during soldering, and furthermore, it does not lower the thermal reliability of the entire substrate even when laminated. At present, photoresists that can be used for the additive method are commercially available, but are still not sufficient.

Accordingly, it is an object of the present invention to form a resist with high pattern accuracy by a photographic method by development using an alkaline aqueous solution, sufficiently withstand the electroless copper plating solution of the full additive method, In addition, it has a heat resistance that can withstand temperatures around 260 ° C in the soldering process, and a solvent resistance to the organic solvent that cleans the flux used at the time of soldering. A composition and a cured product thereof are provided.

[0006]

In order to achieve the above object, a resin composition, a permanent resist resin composition for a printed wiring board, and a cured product thereof according to the present invention have the following composition, and are used as a permanent resist. It is characterized in that it has excellent characteristics and that a printed wiring board using the resist resin composition can be manufactured.

That is, the present invention relates to a monoethylenically unsaturated epoxy compound (a), a hydroxyl group-containing monoethylenically unsaturated compound (b), and optionally a monoethylenically unsaturated compound other than the components (a) and (b). An epoxy group-containing polycarboxylic acid resin (A) which is a reaction product of a copolymerizable epoxy resin (d) which is a reaction product of an unsaturated compound (c) and a polybasic anhydride (e); The present invention relates to a resin composition, a permanent resist resin composition, and a cured product thereof containing B) and a diluent (C).

In the present invention, the epoxy group-containing polycarboxylic acid resin (A) is used. The component (A) comprises a monoethylenically unsaturated group-containing epoxy compound (a), a hydroxyl group-containing monoethylenically unsaturated compound (b), and optionally a monoethylenically unsaturated compound other than the components (a) and (b). A copolymerizable epoxy resin (d), which is a reaction product obtained by copolymerizing (c), and a polybasic acid anhydride (e)
Can be obtained by reacting

Specific examples of the monoethylenically unsaturated group-containing epoxy compound (a) include, for example, glycidyl (meth) acrylate, glycidyl vinyl ether,

[0010]

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[0011]

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And the like. Specific examples of the hydroxyl group-containing monoethylenically unsaturated compound (b) include, for example, 2-hydroxyethyl (meth) acrylate,
Hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxyethyl vinyl ether, 2-hydroxybutyl vinyl ether, cyclohexane-1,4-dimethylol mono (meth) acrylate, cyclohexane-1,4-dimethylol Monovinyl ether and the like can be mentioned.

Specific examples of the monoethylenically unsaturated compound (c) other than the components (a) and (b) include, for example, styrene, α-methylstyrene, (meth) acrylic acid, methyl (meth) acrylate, ethyl Examples thereof include (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, and phenylmaleimide.

The proportion of the components (a), (b) and (c) used is, for example, the sum of (a) + (b) + (c) being 1
When the amount is 00 parts by weight, the amount of the component (a) used is 5 to 70 parts.
Part by weight is preferred, particularly preferably 10 to 50 parts by weight, component (b) is preferably 30 to 95 parts by weight, particularly preferably 50 to 90 parts by weight, and component (c) is 0 to 90 parts by weight.
The amount is preferably from 50 to 50 parts by weight, particularly preferably from 0 to 30 parts by weight.

At the time of the copolymerization reaction of the components (a) to (c), organic solvents (for example, ketones such as ethyl methyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene and tetramethyl benzene) are used as diluents. Hydrogens,
Dipropylene glycol dimethyl ether, glycol ethers such as dipropylene glycol diethyl ether, esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate, carbitol acetate, octane, aliphatic hydrocarbons such as decane, petroleum ether,
It is preferable to use an arbitrary amount of an organic solvent such as a petroleum-based solvent such as petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha. Further, as the polymerization initiator, for example, azo compounds (for example, 2,2'-azobisisobutyronitrile,
2,2'-azobis (2,4-dimethylvaleronitrile), 4,4'-azobis-4-cyanovaleric acid and the like, peroxide compounds (for example, cumene hydroperoxide, t-butylperoxy-2-ethyl) Hexanoate, 1,1-di-t-butylperoxy-
3,3,5-trimethylcyclohexane, di-t-butyl peroxide, etc.).

The reaction temperature is preferably from 50 to 100 ° C.
The reaction time is preferably 5 to 30 hours. Thus, the copolymerizable epoxy resin (d) can be obtained.

Next, a copolymerizable epoxy resin (d) and a polybasic anhydride (c) (for example, succinic anhydride, maleic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, Hydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride,
The reaction of trimellitic acid, pyromellitic acid, etc.) is carried out in such a manner that the polybasic anhydride (c) is used in an amount of 0.1 to 1 equivalent of the hydroxyl group in the copolymerizable epoxy resin (d).
It is preferable to react by 1.0 equivalent. Reaction temperature is 60 ~
150 ° C. is preferred. The reaction time is preferably 1 to 10 hours.

The amount of the epoxy group-containing polycarboxylic acid resin (A) contained in the composition of the present invention is from 10 to 80 in the composition.
% By weight, and particularly preferably 15 to 60% by weight.

Next, specific examples of the cationic photopolymerization initiator (B) include, for example,

[0020]

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[0021]

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[0022]

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[0023]

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[0024]

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[0025]

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[0026]

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[0027]

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[0028]

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[0029]

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Sulfonium salts, iodonium salts, pyridinium salts and the like. These cationic photopolymerization initiators (B) can be used alone or in combination of two or more.

The proportion of the cationic photopolymerization initiator (B) used in the composition of the present invention is preferably 0.5 to 20% by weight, and particularly preferably 1 to 10% by weight.

Next, specific examples of the diluent (C) include ketones such as ethyl methyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene, methyl cellosolve, butyl cellosolve, and methyl carbyl. Toll, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, glycol ethers such as dipropylene glycol diethyl ether, ethyl acetate, butyl acetate, butyl cellosolve acetate, esters such as carbitol acetate, ethanol, propanol, Alcohols such as ethylene glycol and propylene glycol; aliphatic hydrocarbons such as octane and decane; stones such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha Mention may be made of the system solvent and the like.

The diluent (C) is used alone or as a mixture of two or more kinds. The amount of the diluent (C) contained in the composition of the present invention is 5 to 80% by weight in the composition. It is preferably from 10 to 70% by weight.

The composition of the present invention may further contain, if necessary, barium sulfate, barium titanate, silicon oxide powder, finely divided silicon oxide, amorphous silica, talc for the purpose of improving properties such as adhesion and hardness. Known inorganic fillers such as clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, and mica powder can be used. The amount used is from 0 to 60% by weight in the composition of the present invention.
Is particularly preferable, and particularly preferably 5 to 40% by weight.

Further, if necessary, known and customary coloring agents such as phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, carbon black and naphthalene black, hydroquinone, hydroquinone monomethyl ether, etc. Known and commonly used polymerization inhibitors, known and commonly used thickeners such as asbestos, benton and montmorillonite, silicone-based, fluorine-based, polymer-based antifoaming agents and / or leveling agents, imidazole-based, thiazole-based, triazole Known and commonly used additives such as a system and an adhesion imparting agent such as a silane coupling agent can be used.

Known and commonly used binder resins such as copolymers of ethylenically unsaturated compounds such as acrylic esters, polyester resins synthesized from polyhydric alcohols and polybasic acid compounds, and epoxy ( Meth) acrylate, epoxy (meth) acrylate, polybasic anhydride reactant, polyester (meth) acrylate,
Photopolymerizable oligomers such as polyurethane (meth) acrylate, photopolymerizable monomers such as trimethylolpropane tri (meth) acrylate, dipentaerythritol penta and hexa (meth) acrylate, and epoxy resins also have various properties as resists. It can be used within a range that does not affect the operation.

The composition of the present invention can be obtained by blending the blended components preferably in the ratio described above and uniformly mixing them with a roll mill or the like.

The permanent resist resin composition of the present invention is cured, for example, as follows to obtain a cured product. That is, it is applied on the laminate in a thickness of 10 to 160 μm,
After drying at 10 ° C., the negative film is brought into direct contact with the coating film, and then irradiated with ultraviolet light, and the unexposed portion is diluted with a dilute alkaline aqueous solution (for example, a 0.5 to 2% aqueous sodium carbonate solution).
And dissolved (developed). After washing, drying and irradiating the entire surface with ultraviolet rays, the product is cured by heating at 150 ° C. for 30 minutes to obtain a cured product.

[0039]

The present invention will be described more specifically below with reference to examples.

(Synthesis Example of Epoxy Group-Containing Polycarboxylic Acid Resin (A)) Synthesis Example 1 A flask was charged with 1144.2 parts of propylene glycol monomethyl ether acetate, and nitrogen gas was blown into the flask with stirring, followed by heating to 90 ° C. When the temperature became constant at 90 ° C., 500 parts of 2-hydroxyethyl methacrylate, 200 parts of methyl methacrylate, 300 parts of glycidyl methacrylate and 15 parts of azobisisobutyronitrile were mixed in a flask over 2.5 hours. The mixture was added dropwise and then kept at 90 ° C. for 3 hours while stirring.
After 3 hours, a solution prepared by dissolving 3 parts of azobisisobutyronitrile in 100 parts of propylene glycol monomethyl ether acetate was dropped into the flask over 10 minutes, and then the mixture was kept at 90 ° C for 4 hours while stirring. Then 60 ° C
Then, 376.4 parts of tetrahydrophthalic anhydride and 460 parts of propylene glycol monomethyl ether acetate were charged, heated to 90 ° C., and reacted for 10 hours to obtain an epoxy group-containing polycarboxylic acid resin (A-1). . The solid content acid value (mg KOH / g) of the product is 100
The epoxy equivalent of the solid content was 657.6, and the weight average molecular weight was 35,000. The solids content of the product solution is 45% by weight
Met.

Synthesis Example 2 A flask was charged with 1144.2 parts of propylene glycol monomethyl ether acetate, and nitrogen gas was blown into the flask while stirring to heat the mixture to 90 ° C. When the temperature becomes constant at 90 ° C., 2-hydroxyethyl acrylate 5
00 parts, ethyl methacrylate 100 parts, glycidyl methacrylate 400 and azobisisobutyronitrile 1
The liquid obtained by mixing 5 parts was kept warm for 2.5 hours. After 3 hours, a solution prepared by dissolving 3 parts of azobisisobutyronitrile in 100 parts of propylene glycol monomethyl ether acetate was dropped into the flask over 10 minutes, and then kept at 90 ° C for 4 hours while stirring at 90 ° C. Next, the mixture was cooled to 60 ° C., charged with 359 parts of hexahydrophthalic anhydride and 438.8 parts of propylene glycol monoethyl ether acetate, heated to 90 ° C., and reacted for 10 hours to obtain an epoxy group-containing polycarboxylic acid resin (A-2). Obtained. The solid content acid value (mgKOH / g) of the product is 95, the epoxy equivalent of the solid content is 4
89, the weight average molecular weight was 29,000. The solids content of the product solution was 45% by weight.

Synthesis Example 3 A flask was charged with 1144.2 parts of propylene glycol monomethyl ether acetate, and nitrogen gas was blown into the flask with stirring, followed by heating to 90 ° C. When the temperature became constant at 90 ° C., 500 parts of 4-hydroxybutyl methacrylate, 100 parts of ethyl methacrylate, and 400 parts of a compound having the following structural formula

[0043]

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And azobisisobutyrol nitrile 15
The mixture was heated for 2.5 hours. After 3 hours, a solution prepared by dissolving 3 parts of azobisisobutyronitrile in 100 parts of propylene glycol monomethyl ether acetate was added.
The mixture was dropped into the flask over a period of 0 minutes, and then the mixture was kept at 90 ° C. for 4 hours while stirring. Next, the mixture was cooled to 60 ° C., and 221 parts of succinic anhydride and 270.1 parts of propylene glycol monomethyl ether acetate were charged, heated to 90 ° C., and reacted for 10 hours to obtain an epoxy group-containing polycarboxylic acid resin (A-3). . Acid value of solid content of product (mgKOH
/ G) was 100, the epoxy equivalent of the solid content was 563, and the weight average molecular weight was 25,000. The solids content of the product solution was 45% by weight.

Examples 1 to 1 Permanent resist resin compositions were mixed, dispersed and kneaded in accordance with the compositions shown in Table 1 (the numerical values are parts by weight). The resulting composition was applied on a laminate at a thickness of 30 μm, dried at 80 ° C. for 60 minutes, then contacted with negative mask on the resist, and irradiated with ultraviolet rays using an ultra-high pressure mercury lamp. The unexposed portion was developed with a 1.5% aqueous NaCO ₃ solution for 60 seconds at a spray pressure of 2.0 kg / cm ² . (The heat treatment can be performed before the development.) After washing with water and drying, the entire surface was irradiated with ultraviolet rays and then heat-treated at 150 ° C. for 30 minutes. This was immersed in an electroless copper plating solution at 70 ° C. for 10 hours to form an electroless copper plating film of about 20 μm, thereby producing an additive-processed multilayer printed wiring board. Table 1 shows the results of evaluating the resist characteristics in the process of obtaining the additive multilayer printed wiring board in this manner.

Evaluation method (developability) ・ ・ ・: At the time of development, the ink was completely removed and development was possible. ×: At the time of development, a small amount of residue remains, and there is a part that is not developed. (Solvent resistance) The cured resist film was immersed in acetone for 20 minutes and the state was visually observed. ○ ・ ・ ・ ・ No change at all. ×: blisters and peeling occurred. (Plating resistance) ○ ・ ・ ・ ・ No change is observed in the electroless copper plating process. C: Discoloration, blistering, and peeling occurred in the electroless copper plating step. (Solder Heat Resistance) According to the test method of JIS C 6481, the test piece was immersed in a solder bath at 260 ° C. for 10 seconds three or two times, and the change in appearance was evaluated.

(Post-Flux Resistance) The immersion for 10 seconds was performed three times, and the change in appearance was evaluated. ○ ・ ・ ・ ・ No change in appearance △ ・ ・ ・ ・ Discoloration of the cured film is observed × ・ ・ ・ ・ Floating, peeling and solder dipping of the cured film Note) Post flux used (rosin type): JIS
Use flux according to C 6481.

(Flux resistance for leveler) The immersion was performed twice for 10 seconds, and the appearance was evaluated after immersion in boiling water for 10 minutes. ○ ・ ・ ・ No change in appearance △ ・ ・ ・ ・ Discoloration of the cured film is observed × ・ ・ ・ ・ Floating, peeling and solder dipping of the cured film Note) Flux for leveler used: manufactured by MEC Corporation ,
W-121 (shell life of resist composition)
The state after being left at 0 ° C. for one month was observed. ○ ・ ・ ・ ・ No change in viscosity or other appearance. Δ: The viscosity is slightly increased. X: Gelled.

[0049]

Table 1 Example 1 2 3 4 5 5 Epoxy group-containing polycarbonate resin (A-1) obtained in Synthesis Example 1 92.9 46.4 Epoxy group-containing polycarbonate resin (A-2) obtained in Synthesis Example 2 87 46.5 87 Epoxy group-containing polycarbonate resin (A-3) obtained in Synthesis Example 3 87 SP-170 * 16 UVI-6990 * 2 10 PCI-061 * 34 44 propylene glycol monomethyl ether acetate 20 20 20 20 20 EOCN-104S * 4 10 15 15 10 10 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate 3.5 3.5 3.5 3.5 KAYARAD DPHA * 5 8.5 Lucirin TPO * 6 1.0 Silica dioxide 30 30 30 30 30 Phthalocyanine green (color pigment) 1.0 1.0 1.0 1.0 1.0 Aerosil 380 * 7 1.0 1.0 1.0 1.0 1.0 Off ○ ○ ○ ○ ○ developability ○ ○ ○ ○ ○ solvent resistance ○ ○ ○ ○ ○ resistance to plating solution ○ ○ ○ ○ ○ Soldering heat resistance, flux resistance for post flux resistance ○ △ ○ ○ ○ leveler ○ △ ○ ○ ○

Note) * 1 SP-170: a photocationic polymerization initiator manufactured by Asahi Denka Kogyo KK, diluted with propylene carbonate at 40%. * 2 UVI-6990: a photocation polymerization initiator manufactured by Union Carbide Co., Ltd. Propylene carbonate 50% diluted product. * 3 PCI-061: Nippon Kayaku Co., Ltd., cationic photopolymerization initiator yellow powder, structural formula:

[0051]

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Is as follows. * 4 EOCN-104S: Nippon Kayaku Co., Ltd., cresol novolak type, epoxy resin, epoxy equivalent 220, softening point 92 ° C. * 5 KAYARAD DPHA: Nippon Kayaku Co., Ltd.
Mixture of dipentaerythritol penta and hexaacrylate. * 6 Lucilin TPO: photo radical polymerization initiator manufactured by BASF * 7 Aerosil 380: Nippon Aerosil Co., Ltd.
Made, anhydrous silica

From the evaluation results shown in Table 1, the resin composition of the present invention has a long shelf life and is excellent in developability of dilute alkaline aqueous solution, and the cured product has good solvent resistance, plating resistance and solder heat resistance. Are better.

[0054]

The resin composition, the permanent resist resin composition and the cured product of the present invention have high resolution and are easy to develop with a dilute aqueous alkali solution, but they are isopropyl alcohol, trichloroethylene and methylene chloride. Excellent solvent resistance to acetone, etc., excellent plating solution resistance to electroless plating performed for a long time under high temperature and high alkalinity conditions, and heat resistance to withstand temperatures around 260 ° C in the soldering process. Particularly suitable for the production of printed wiring boards.

Claims (3)

[Claims] 1. An epoxy compound containing a monoethylenically unsaturated group (a), a monoethylenically unsaturated compound containing a hydroxyl group (b) and optionally a monoethylenically unsaturated compound other than the components (a) and (b) ( (c) an epoxy group-containing polycarboxylic acid resin (A) which is a reaction product of a copolymerizable epoxy resin (d) as a reaction product and a polybasic anhydride (e), a cationic photopolymerization initiator (B), and dilution A resin composition containing an agent (C). 2. A permanent resist resin composition comprising the epoxy group-containing polycarboxylic acid resin (A) according to claim 1, a cationic photopolymerization initiator (B) and a diluent (C). 3. A cured product of the resin composition according to claim 1 or 2.