JPH1097070A - Resin composition, permanent resist resin composition and their cured bodies - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin compsn. having high resolution, readily developable with an aq. alkali soln. and excellent also in solvent and plating solution resistances by incorporating epoxy-contg. polycarboxylic acid resin having a specified structure, a photo cationic polymn. initiator and a diluent. SOLUTION: This resin compsn. contains epoxy-contg. polycarboxylic acid resin, a photo cationic polymn. initiator and a diluent. The polycarboxylic acid resin is obtd. by allowing an epoxy compd. having two of more epoxy groups in one molecule to react with a compd. having one or more hydroxyl groups and one carboxyl group in one molecule and allowing the resultant reactional product to further react with a polybasic acid anhydride. This resin compsn. has superior characteristics as a permanent resist and can produce a printed circuit board. An inorg. filler such as barium sulfate or barium titanate may further be used in this resin compsn. so as to improve characteristics such as adhesion and hardness.

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 are manufactured by using a copper-clad laminate and by a subtractive method in which unnecessary portions of a copper foil circuit are removed by etching. It has drawbacks that it is difficult to form a wiring board, and that small-diameter through holes and via holes cannot be uniformly formed by electroplating. Is the current situation.

[0003] 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, which has been considered suitable for general consumer use, has begun to be put into practical use 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 photo-additive 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, an object of the present invention is 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, and A permanent resist functional composition that has heat resistance to withstand temperatures around 260 ° C in the soldering process and solvent resistance to organic solvents that clean flux used during soldering, and is used without removing it to the final product And a cured product thereof.

[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 an epoxy compound (a) having at least two epoxy groups in a molecule and a compound (b) having at least one hydroxyl group and one carboxyl group in one molecule. An epoxy group-containing polycarboxylic acid resin (A), a photocationic polymerization initiator (B), and a diluent (C), which are reactants of the reactant (I) and the polybasic acid anhydride (c). The present invention relates to a resin composition, a permanent resist resin composition, and a cured product thereof.

In the present invention, the epoxy group-containing polycarboxylic acid resin (A) is used. Specific examples of the component (A) include, for example, an epoxy compound (a) having at least two epoxy groups in one molecule and a compound having at least one hydroxyl group and one carboxyl group in one molecule. A reaction product of the reaction product (I) of (b) and the polybasic acid anhydride (c) can be exemplified. The component (A) is obtained by reacting an epoxy compound (a) having at least two epoxy groups in one molecule with a compound (b) having at least one hydroxyl group and one carboxyl group in one molecule. Then, the reaction product (I) can be obtained by reacting the polybasic acid anhydride (c).

The reactant (I) has at least 2 molecules per molecule.
Epoxy compound (a) having at least two epoxy groups and 1
It can be obtained by reacting a compound (b) having at least one or more hydroxyl group and one carboxyl group in the molecule. Specific examples of the epoxy compound (a) having at least two or more epoxy groups in one molecule include, for example, novolak-type epoxy resins (for example, phenols such as phenol, cresol, halogenated phenol and alkylphenol, and formaldehyde). Novolaks obtained by a reaction under an acidic catalyst and epichlorohydrin and / or methylepichlorohydrin, etc. Commercially available products are EOCN-103, EOCN-104, manufactured by Nippon Kayaku Co., Ltd.
S, EOCN-102, EOCN-1027, EPPN
-201, BREN-S; DEN, manufactured by Dow Chemical Company
-431, DEN-439; manufactured by Dainippon Ink and Chemicals, Inc., N-730, N-770, N-865, N-
665, N-673, VH-4150, etc.) and bisphenol-type epoxy resins (for example, obtained by reacting bisphenols such as bisphenol A, bisphenol F, bisphenol S and tetrabromobisphenol A with epichlorohydrin and / or methyl epichlorohydrin. And those obtained by reacting a diglycidyl ether of bisphenol A or bisphenol F with a condensate of the above bisphenols and epichlorohydrin and / or methyl epichlorohydrin.
As commercially available products, Yuko Shell Epoxy Co., Ltd., Epicoat 1004, Epicoat 1002, Epicoat 400
2, Epicoat 4004, etc. ), Trisphenol methane type epoxy resin (for example, trisphenol methane,
Those obtained by reacting triscresol methane or the like with epichlorohydrin and / or methyl epichlorohydrin. Commercial products include Nippon Kayaku Co., Ltd., EP
PN-501, EPPN-502 and the like. ), Tris (2,
3-epoxypropyl) isocyanurate, biphenyl diglycidyl ether, other, manufactured by Daicel Chemical Industries, Ltd., celloxide 2021; manufactured by Mitsui Petrochemical Industries, Ltd., Epomic VG-3101; manufactured by Yuka Shell Epoxy, E -1031S; Nippon Soda Co., Ltd., E
Alicyclic epoxy resins such as PB-13 and EPB-27, copolymerized epoxy resins (for example, CP-50M, CP-50S manufactured by NOF Corporation, which is a copolymer of glycidyl methacrylate, styrene and methylstyrene) Or
Copolymers of glycidyl methacrylate and cyclohexylmaleimide, etc.). Alternatively, other examples include an epoxy resin having a special structure. Particularly preferred are, for example, cresol novolak type epoxy resin, phenol novolak type epoxy resin and the like.

Next, a compound (b) having at least one hydroxyl group and one carboxyl group in one molecule.
As specific examples, for example, dimethylolpropionic acid, dimethylolacetic acid, dimethylolbutyric acid, dimethylolvaleric acid, polyhydroxy-containing monocarboxylic acids such as dimethylolcaproic acid, hydroxypivalic acid, monohydroxy-containing such as p-hydroxybenzoic acid Monocarboxylic acids and the like can be mentioned.

The reaction between the epoxy compound (a) and the compound (b) is carried out in such a manner that the carboxylic acid of the compound (b) is used in an amount of 0.01 to 1 equivalent of the epoxy group of the epoxy compound (a).
0.5 mol is preferred, and particularly preferably 0.1 to 0.1 mol.
3 moles.

In the reaction, ketones such as ethyl methyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene, and glycol ethers such as dipropylene glycol dimethyl ether and dipropylene glycol diethyl ether are used as diluents. Ethyl acetate, butyl acetate, butyl cellosolve acetate, esters such as carbitol acetate, aliphatic hydrocarbons such as octane, decane, and organic solvents such as petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, solvent naphtha, etc. It is preferred to use the class. Further, it is preferable to use a catalyst (for example, triphenylphosphine, benzyldimethylamine, methyltriethylammonium chloride, triphenylstibine, chromium octanoate, etc.) to accelerate the reaction, and particularly preferably, after the reaction, By using an organic peroxide or the like, the used catalyst is subjected to an oxidation treatment, whereby the catalytic activity is made substantially inactive. The amount of the catalyst used is preferably 0.1 to 10 based on the reaction raw material mixture.
% By weight. In order to prevent polymerization during the reaction, it is preferable to use a polymerization inhibitor (e.g., hydroquinone, methylhydroquinone, p-methoxyphenol, catechol, pyrogallol, etc.). Preferably it is 0.01 to 1% by weight. The reaction temperature is 60 to 150 ° C. The reaction time is preferably 5 to 30 hours. Thus, the reactant (I) can be obtained.

Next, reactant (I) and polybasic anhydride (c) (for example, succinic anhydride, maleic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride) Acid, methylendomethylenetetrahydrophthalic anhydride, trimellitic acid, pyromellitic acid, etc.) are reacted with the reaction product (I)
It is preferable to react 0.1 to 1.0 equivalent of the above-mentioned polybasic acid anhydride (c) per equivalent of the hydroxyl group with respect to the hydroxyl group contained therein. The reaction temperature is preferably from 60 to 150C. 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,

[0016]

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[0017]

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[0018]

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[0019]

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

The proportion of the cationic photopolymerization initiator (B) to be used in the composition of the present invention is preferably 0.5 to 20% by weight, 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. Glycol ethers such as tall, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether, ethyl acetate, butyl acetate, esters such as butyl cellosolve acetate, 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 preferably 5 to 80% by weight in the composition. It is 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 stalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, carbon black and naphthalene black, hydroquinone, hydroquinone monomethyl ether And known thickeners such as asbestos, benton, and montmorillonite; defoamers and / or leveling agents such as silicone-based and fluorine-based polymers; imidazole-based, thiazole-based and 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 acrylates, polyester resins synthesized from polyhydric alcohols and polybasic acid compounds, and epoxy ( Reaction products of polybasic anhydrides of meth) acrylate and epoxy (meth) acrylate, photopolymerizable oligomers such as polyester (meth) acrylate and polyurethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol Penta and hexa (meta)
Photopolymerizable molmers such as acrylates and epoxy resins can also be used as long as they do not affect various properties as a resist.

The composition of the present invention can be obtained by blending the blended components preferably in the above-mentioned ratios and uniformly mixing 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.

[0035]

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 2200 g of cresol / novolak type epoxy resin (EOCN-104S, Nippon Kayaku Co., Ltd., softening point 92 ° C., epoxy equivalent 220) (10 equivalents), 402 g (3 moles) of dimethylolpropionic acid, 983.8 g of carbitol acetate and 421.6 g of solvent naphtha were charged and heated and stirred at 90 ° C. to dissolve the reaction mixture. Next, the reaction solution was cooled to 60 ° C., 8.0 g (0.03 mol) of triphenolphosphine was charged, heated to 100 ° C., reacted for about 10 hours, and the acid value (mg KOH / g) was 0.5 mg KOH / g. g, then cooled to 50 ° C., charged with 2.7 g (0.03 mol) of tertiary butyl hydroperoxide, and reacted for about 1 hour to oxidize the reaction catalyst triphenylphosphine. Activity was inactivated. Then, 317.2 g (2.09 mol) of tetrahydrophthalic anhydride, 119.7 g of carbitol acetate and solvent naphtha.
1 g was charged and reacted at 95 ° C. for 10 hours to obtain an epoxy group-containing polycarboxylic acid resin (A-1). The epoxy equivalent of the product (solid content) was 418 and the acid value (mg KOH
/ G) was 40.

Synthesis Example 2 2200 g (10 equivalents) of a cresol novolak type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., EOCN-104S, softening point 92 ° C., epoxy equivalent 220), 268 g (2 mol) of dimethylolpropion, Toll 933.
1 g and 399.9 g of solvent naphtha were charged, and 90
The mixture was heated and stirred at ℃ to dissolve the reaction mixture. Then, the reaction solution was cooled to 60 ° C., and 7.6 g of triphenylphosphine was added.
(0.029 mol) and heated to 100 ° C., about 1
0 hours reaction, acid value (mgKOH / g) 0.5mgK
When the concentration of OH / g was reached, the mixture was cooled to 80 ° C., charged with 4.46 g (0.029 mol) of cumene hydroperoxide, and reacted at 80 ° C. for 3 hours to convert triphenylphosphine into triphenylphosphine oxide. An oxidation reaction was performed to inactivate the catalytic activity. Then 387.8 g (2.55 mol) of tetrahydrophthalic anhydride,
146.2 g of carbitol acetate and 62.6 g of solvent naphtha were charged and reacted at 95 ° C. for 10 hours to obtain an epoxy group-containing polycarboxylic acid resin (A-2). The epoxy equivalent of the product (solid content) was 357.9,
The acid value (mgKOH / g) was 50.

Synthesis Example 3 In Synthesis Example 1, a cresol novolak type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., EOCN-104S, softening point 92)
2200 g of phenol-novolak type epoxy resin (Nippon Kayaku Co., Ltd., EPPN)
-201, softening point 67 ° C, epoxy equivalent 200) 200
The reaction was carried out in the same manner as in Synthesis Example 1 except that the amount was changed to 0 g (10 equivalents) to obtain an epoxy group-containing polycarboxylic acid resin (A-3). The epoxy equivalent of the product (solid content) was 390, and the acid value (mgKOH / g) was 43.

Examples 1 to 5 Permanent resist resin compositions were mixed, dispersed and kneaded in accordance with the composition shown in Table 1 (the numerical values are parts by weight). The obtained composition was applied on a laminate at a thickness of 30 μm, dried at 80 ° C. for 60 minutes, then brought into contact with a negative mask on the resist, and irradiated with ultraviolet rays using an ultra-high pressure mercury lamp. The unexposed portion is treated with 1.5% Na ₂ CO ₃ aqueous solution 6
Development was performed for 0 second at a spray pressure of 2.0 kg / cm ² .
(It can be heat-treated before development.)
After irradiating the entire surface with ultraviolet rays, a heat treatment was performed 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, 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 carried out twice for 10 seconds, and after immersion in boiling water for 10 minutes, 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) Flux for leveler used: manufactured by MEC Corporation ,
W-121 (Shelf life of resist composition) The state of the resist composition left at 40 ° C. for one month was observed. ○ ・ ・ ・ No change in viscosity or other appearance. Δ: The viscosity is slightly increased. X: Gelled.

[0043]

Table 1 Example 1 Epoxy-containing polycarboxylic acid resin (A-1) 154 obtained in Synthesis Example 1 154 154 Epoxy-containing polycarboxylic acid resin (A-2) 154 obtained in Synthesis Example 2 154 Epoxy-containing polycarboxylic acid resin (A-3) obtained in Synthesis Example 3 157.9 SP-170 * 16 UVI-6990 * 2 10 10 PCI-061 * 35 55 Propylene glycol monomethyl ether acetate 10 25 25 25 25 EOCN -104S * 4 25 10 25 10 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate 20 20 KAYARD DPHA * 5 20 Lucillin TPO * 6 1 Silica dioxide 60 75 75 75 75 Aerosil 380 * 7 5 5 5 55 Phthalocyanine green (color pigment) 1.5 1.8 1.8 1.8 1.8 Shell life of resist composition ○ ○ ○ ○ ○ Developability ○ ○ ○ ○ ○ Solvent resistance ○ ○ ○ ○ ○ Plating solution ○ ○ △ ○ △ Solder heat resistance Post flux resistance △ ○ ○ ○ ○ Leveler flux resistance ○ ○ ○ ○ ○

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

[0045]

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Is as follows. * 4 EOCN-104S: Nippon Kayaku Co., Ltd., cresol novolak type epoxy resin, epoxy equivalent 2
20, 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 a dilute alkaline aqueous solution, and the cured product has good solvent resistance, plating resistance and solder heat resistance. Are better.

[0048]

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. It has excellent solvent resistance to acetone, etc., excellent resistance to Met solution for 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.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H05K 3/46 H05K 3/46 T

Claims (3)

[Claims] A reaction product of an epoxy compound (a) having at least two or more epoxy groups in one molecule and a compound (b) having at least one hydroxyl group and one carboxyl group in one molecule ( Epoxy group-containing polycarboxylic acid resin (A) which is a reaction product of I) and polybasic acid anhydride (c), cationic photopolymerization initiator (B) and diluent (C)
A resin composition comprising: 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.