JP2002232148A - Thermosetting resin composition for wiring board, its molding and multilayer printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermosetting resin composition for wiring board, in which a uniformly set coating can be obtained by eliminating the problems caused by dicyandiamide and an insulation layer exhibiting superior essential characteristics of epoxy resin, e.g. adhesion with respect to a conductor layer, heat resistance and interlayer insulation reliability (moisture resistance), can be formed, its molding and a multilayer printed wiring board produced by using them. SOLUTION: The resin composition comprises (A) an epoxy resin, having two or more epoxy groups with a single molecule, (B) a rubber component, (C) a filler component being decomposed or dissolved by a roughening agent, and (D) monoepoxide additive of dicyandiamide as an epoxy resin hardening agent, wherein the monoepoxide additive of dicyandiamide (D) is dissolved in a diethylene glycol or dipropylene glycol based ether or based solvent and is dispersed uniformly into the composition. A molding of the thermosetting resin composition and a multilayer printed wiring board produced by using them are also provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer printed wiring board in which conductive circuit layers and insulating layers are alternately built up.
The present invention relates to a thermosetting resin composition for a wiring board capable of forming an insulating layer having excellent interlayer insulation reliability, a molded product thereof, and a multilayer printed wiring board manufactured using the same.

[0002]

2. Description of the Related Art In general, in a multilayer printed wiring board in which conductive circuit layers and insulating layers are alternately built up, an epoxy resin composition is widely used as a resin composition constituting the insulating layer. As an epoxy resin curing agent for this epoxy resin composition, dicyandiamide, which is effective in toughness, heat resistance, and moisture resistance, is known, but with this curing agent alone, curing requires a relatively long time at a relatively high temperature. I have.
As this improvement, a low-temperature fast-curing curing agent system comprising dicyandiamide and an imidazole compound has been proposed.

[0003] However, in this curing agent system, the reaction speed is high, and stress remains in the cured coating film. Therefore, in a multilayer printed wiring board in which an insulating layer is built up without using a glass cloth, there have been problems such as warpage and cracks due to heating.

On the other hand, dicyandiamide is solid at room temperature, hardly dissolves in a solvent that dissolves epoxy resin at room temperature, and can be uniformly mixed in epoxy resin even when mechanically kneaded using a three-roll mill or the like. Was difficult to disperse. Therefore, when a resin composition containing such dicyandiamide as an epoxy curing agent is used as an interlayer insulating material of a multilayer printed wiring board, dicyandiamide remains as particles in the epoxy resin composition, and a uniform coating film cannot be obtained. There has been a problem that the intrinsic properties of the epoxy resin are reduced, especially the electrical properties are reduced. Such a problem is particularly remarkable in a recent situation where further increase in the number of layers and densification of a printed wiring board is required.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems caused by dicyandiamide,
A thermosetting for wiring boards that can provide a uniform cured coating film and can form an insulating layer that exhibits the inherent properties of epoxy resin such as adhesion to conductor layers, heat resistance, and interlayer insulation reliability (moisture resistance). SUMMARY OF THE INVENTION An object of the present invention is to provide a conductive resin composition and a molded article thereof, and a multilayer printed wiring board produced using the same.

[0006]

The present inventors have paid attention to a monoepoxide adduct of dicyandiamide, which functions as an epoxy resin curing agent in the same manner as dicyandiamide.
However, the monoepoxide adduct of dicyandiamide has the disadvantage that, although it can be liquefied, it does not recrystallize at room temperature to obtain a uniform mixed state of the epoxy resin composition, and methyl ethyl ketone, a common solvent for epoxy resins. It has been found that there is a drawback that when a uniform mixed state is obtained by dissolving in ethyl acetate or ethyl acetate, the printability is reduced (the storage stability is reduced) due to an increase in viscosity.

The inventor has further studied diligently to achieve the above object. As a result, the monoepoxide adduct of dicyandiamide is easily soluble in a diethylene glycol-based or dipropylene glycol-based ether-based solvent. The liquefied epoxy resin curing agent was found to be excellent in storage stability, and was found to be in a stable and uniform mixed state in the epoxy resin composition, thereby completing the present invention.

That is, the thermosetting resin composition for a wiring board of the present invention comprises (A) an epoxy resin having at least two epoxy groups per molecule, (B) a rubber component, and (C) a rubber component.
A resin composition containing a filler component that is decomposed or dissolved by a roughening agent, and (D) a monoepoxide adduct of dicyandiamide as an epoxy resin curing agent, wherein the monoepoxide adduct of dicyandiamide (D) is a diethylene glycol-based or It is characterized by being dissolved in a dipropylene glycol-based ether-based solvent and uniformly mixed and dispersed in the composition.

In a preferred embodiment, the epoxy resin (A) has a bisphenol A type epoxy resin (A1) having an epoxy equivalent of 400 or more and two or more epoxy groups in one molecule having an epoxy equivalent of less than 400. The epoxy resin (A2), and the weight ratio of the epoxy resin (A1) to the epoxy resin (A2) is preferably in the range of 30:70 to 90:10. The rubber component (B) contains epoxidized polybutadiene in a proportion of 40 parts by weight or less, preferably 5 to 30 parts by weight, based on 100 parts by weight of the epoxy resin (A). Calcium is added to 70 parts by weight of the epoxy resin (A).
It is preferable that the content is not more than 5 parts by weight, preferably 5 to 50 parts by weight. The monoepoxide adduct of dicyandiamide (D) is preferably contained in a proportion of 1 to 40 parts by weight in an outer frame amount with respect to 100 parts by weight of the epoxy resin (A). The monoepoxide adduct of dicyandiamide (D) is preferably dissolved in a diethylene glycol-based or dipropylene glycol-based ether-based solvent in a proportion of 100 parts by weight or less based on 100 parts by weight of the adduct.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The first feature of the thermosetting resin composition for a wiring board of the present invention is that a monoepoxide adduct of dicyandiamide is used as an epoxy resin curing agent. This makes the thermosetting reaction of the epoxy resin milder than when dicyandiamide is used. As a result, the toughness and thermal stability of the cured coating film are improved, and the cured coating film is excellent in crack resistance due to mechanical shock and thermal shock. This can be seen from the measurement results of differential thermal analysis (FIGS. 1 and 2) of the epoxy resin composition containing dicyandiamide (Comparative Example 2) and the epoxy resin composition containing the dicyandiamide monoepoxide adduct (Example 1). it is obvious. Moreover, the monoepoxide adduct of dicyandiamide has excellent compatibility with the epoxy resin, and the cured product obtained exhibits extremely excellent properties such as the inherent moisture resistance (insulation reliability), heat resistance, and adhesion of the epoxy resin.

The thermosetting resin composition for a wiring board of the present invention comprises:
A second feature is that a monoepoxide adduct of dicyandiamide as an epoxy resin curing agent is dissolved in a diethylene glycol-based or dipropylene glycol-based ether-based solvent to form a homogeneous mixture. According to such a thermosetting resin composition for a wiring board of the present invention, since the storage stability is excellent, there is no deterioration in printability due to an increase in viscosity, and the obtained cured coating film has neither a compounded state nor a dispersed state. It will be uniform. As a result, the surface roughening state of the insulating layer becomes uniform, and excellent peel strength can be stably obtained.

Hereinafter, each component of the thermosetting resin composition for a wiring board of the present invention will be described in detail. First, the epoxy compound (A) having at least two or more epoxy groups in one molecule is not particularly limited. For example, bisphenol A type epoxy resin, brominated epoxy resin, novolak type epoxy resin, Bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, glycidylamine type epoxy resin, hydantoin type epoxy resin, alicyclic epoxy resin, trihydroxyphenylmethane type epoxy resin, bixylenol type or biphenyl type epoxy resin, bisphenol S Epoxy resin, bisphenol A novolak epoxy resin, tetraphenylolethane epoxy resin, heterocyclic epoxy resin, diglycidyl phthalate resin, tetraglycidyl xylenoyl ethane resin, naphthalene group-containing epoxy Resins, epoxy resins having a dicyclopentadiene skeleton, glycidyl methacrylate copolymerization system epoxy resins and further copolymerized epoxy resins such cyclohexyl maleimide and glycidyl methacrylate. These epoxy resins may be used alone or in combination of two or more.

In the present invention, this epoxy resin (A) is a bisphenol A type epoxy resin having an epoxy equivalent of 400 or more so that the cured coating film is decomposed or dissolved by a roughening agent to obtain a roughened surface having irregularities. (A1) and an epoxy resin (A2) having two or more epoxy groups in one molecule having an epoxy equivalent of less than 400, and the weight ratio of the epoxy resins (A1) and (A2) is from 30:70 to 90:
It is preferably in the range of 10.

The component (A1) has an epoxy equivalent of 400 or more, has at least one hydroxyl group which is easily decomposed or dissolved by a roughening agent, and has a large epoxy equivalent, so that the crosslinking density is high. Is relatively low and is therefore easily roughened by the roughening agent. On the other hand, (A
The component 2) is an epoxy resin having an epoxy equivalent of less than 400 and having two or more epoxy groups in one molecule. The number of hydroxyl groups is smaller or not present as compared with the component (A1). Since the epoxy equivalent is small, the epoxy equivalent becomes high and is hardly decomposed or dissolved by the roughening agent. Therefore,
Contrast of the degree to be decomposed or dissolved by the roughening agent can be obtained, and a roughened surface structure can easily form an uneven surface structure on the surface of the resin insulating layer. The roughened uneven surface of the resin insulating layer functions as an anchor for the conductor layer formed thereon. Therefore, when a conductor layer is formed thereon by electroless plating or electrolytic plating, the adhesion strength between the resin insulation layer and the conductor layer is improved, and a multilayer printed wiring board having excellent adhesion can be manufactured. Further, since the resin insulating layer is formed from a cured coating film of an epoxy resin, a multilayer printed wiring board excellent in heat resistance, electrical insulation and the like can be obtained.

As the bisphenol A type epoxy resin (A1), for example, Japan Epoxy Resin Co., Ltd.
Epicoat 1001 and Epicoat 1004 manufactured by Dainippon Ink and Chemicals, Inc.
050, YD-011 manufactured by Toto Kasei, D.C. E. FIG. R. 661, Araldite 6071, Araldite 7072, AER- manufactured by Asahi Kasei Epoxy Co., Ltd.
661, AER-664, Sumi-Epoxy ESA-011, ESA-012, ESA-01 manufactured by Sumitomo Chemical Co., Ltd.
4 and the like. Further, a brominated epoxy resin having an epoxy equivalent of 400 or more obtained by brominating a bisphenol A type epoxy resin may be used.

The bisphenol A type epoxy resin (A1) having an epoxy equivalent of 400 or more is contained in an amount of 30 to 90 parts by weight, preferably 50 to 80 parts by weight, per 100 parts by weight of the epoxy resin component used. Epoxy equivalent is 400
When the bisphenol A type epoxy resin (A1) is contained in a proportion of less than 30 parts by weight in 100 parts by weight of the epoxy resin component used, the cured resin insulating layer is subjected to a surface roughening treatment with a roughening agent. Even on the surface of the resin insulation layer,
It is not preferable because it becomes difficult to form an uneven surface structure that sufficiently functions as an anchor for the conductor layer formed thereon.
On the other hand, if it is 90 parts by weight or more, a problem occurs in the solder heat resistance.

As the epoxy resin of the component (A2), known epoxy compounds (including epoxy oligomers) having an epoxy equivalent of less than 400 and having at least two epoxy groups in one molecule can be used. For example, bisphenol A epoxy resin such as Epicoat 828 manufactured by Yuka Shell Co., Epicron 840 manufactured by Dainippon Ink and Chemicals, Epototo YD-128 manufactured by Toto Kasei, or bisphenol F epoxy resin, bisphenol S Epoxy resin, phenol novolak epoxy resin, cresol novolak epoxy resin, aliphatic cyclic epoxy resin, epoxy resin containing triazine nucleus, biphenyl epoxy resin, brominated epoxy resin, dimer acid-modified epoxy resin, trihydroxyphenylmethane Epoxy resins, hydrogenated bisphenol A type epoxy resin, glycidyl amine type epoxy resins, tetraphenylolethane type epoxy resins, heterocyclic epoxy resins, phosphorus-containing epoxy resins.

Next, the thermosetting resin composition for a wiring board of the present invention contains a rubber component (B) as an essential component.
Thereby, the adhesion strength can be improved as a stress relaxing agent for the coating film after the surface roughening treatment. Examples of the rubber component include polybutadiene rubber (for example, R-45 manufactured by Idemitsu Kosan Co., Ltd.).
HT, etc.), urethane modified, maleated, epoxy modified,
Various polybutadiene rubber derivatives such as (meth) acryloyl-modified (for example, epoxy-modified PB manufactured by Daicel Chemical Industries, Ltd.)
-3600 etc.), nitrile rubber (for example, NSR manufactured by JSR Corporation)
280, N230S, etc.), CTBN (eg, 1300-31 manufactured by Ube Industries), CTBN modified epoxy resin (eg, YR-102, YR-450 manufactured by Toto Kasei)
Etc.).

In the thermosetting resin composition for wiring boards of the present invention, a filler component (C) which is decomposed or dissolved by a roughening agent is used in combination with the above-mentioned components. Thereby, as described above, the surface of the resin insulating layer can be easily roughened by the surface roughening treatment, the unevenness can be made deeper, and the adhesion strength to the conductor layer can be further increased. However, if the content exceeds 70 parts by weight with respect to 100 parts by weight of the epoxy resin, the content may be left as a void inside or the electrical insulation may be deteriorated, so that the content is 70 parts by weight or less, preferably 50 parts by weight or less. I do.
Examples of the filler include an organic filler and an inorganic filler. Examples of the organic filler include powdered epoxy resin (eg, TEPIC), melamine resin, benzoguanamine resin (eg, N-30, S, MS, etc., manufactured by Nippon Shokubai Co., Ltd.), urea Resin, cross-linked acrylic polymer (for example, M
R-2G, MR-7G, etc., Sekisui Plastics Co., Ltd., and the like; on the other hand, as the inorganic filler, magnesium oxide, calcium carbonate, zirconium silicate,
Zirconium oxide, calcium silicate, calcium hydroxide, silica and the like can be mentioned, and calcium carbonate is particularly preferable.

These filler components have a particle size of 15
μm or less, preferably 7 μm or less. The reason for this is
If the particle size of the filler is larger than 15 μm, bumps are generated on the surface of the insulating layer, and large anchors are generated in the surface roughening treatment, leading to deterioration in smoothness, interlayer insulation, and moisture resistance.

Next, in the thermosetting resin composition for a wiring board of the present invention, a monoepoxide adduct of dicyandiamide is used as an epoxy resin curing agent used as an essential component together with the epoxy resin. In particular, in the present invention, the monoepoxide adduct of dicyandiamide (D) is dissolved in a diethylene glycol-based or dipropylene glycol-based ether-based solvent and uniformly mixed and dispersed in the composition. The amount of the monoepoxide adduct of dicyandiamide used is preferably such that the amount of active hydrogen in these curing agents is 0.3 to 0.7 equivalent to the amount of epoxy groups in the epoxy resin component. The monoepoxide adduct of dicyandiamide is dissolved in a diethylene glycol-based or dipropylene glycol-based ether solvent at a ratio of 100 parts by weight or less, preferably 20 to 80 parts by weight, based on 100 parts by weight of the adduct. Is preferred. This monoepoxide adduct of dicyandiamide is obtained by reacting dicyandiamide with a monoepoxy compound. Monoepoxides that can be used for the modification of dicyandiamide are compounds having one epoxy group, and the compounds include a saturated or unsaturated aliphatic,
The compound may be an alicyclic, aromatic or heterocyclic compound, and may further contain a substituent such as an ether group in the compound. An epoxy compound having two or more epoxy groups, for example, a diepoxide, gels at the time of adduct formation and cannot be used as a curing agent.

Preferred specific examples of the monoepoxide include phenyl glycidyl ether, tolyl glycidyl ether, xylyl glycidyl ether, cumyl glycidyl ether, simyl glycidyl ether, p-secondary butyl phenyl glycidyl ether and the like. Generally, it is an aryl glycidyl ether.

In the thermosetting resin composition of the present invention,
If necessary, a curing accelerator can be used. Specific examples of the curing accelerator include triethylamine, tributylamine, dimethylbenzylamine, diethylbenzylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N-dimethylbenzylamine, Tertiary amines such as -methyl-N, N-dimethylbenzylamine, quaternary ammonium salts such as benzyltrimethylammonium chloride and benzyltriethylammonium chloride, triethylphosphine,
Phosphines such as triphenylphosphine; phosphonium salts such as n-butyltriphenylphosphonium bromide; imidazole; 2-methylimidazole;
Imidazoles such as ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 1- (2-cyanoethyl) -2-ethyl-4-methylimidazole or their organic acid salts, acetoguanamine, benzoguanamine, etc. Guanamines can be mentioned. Among these, preferred curing accelerators are imidazoles and phosphines.

The thermosetting resin composition of the present invention is desirably adjusted to a viscosity suitable for a coating method using a diethylene glycol-based or dipropylene glycol-based ether solvent, but impairs the uniform dispersion effect of such a solvent. Other common organic solvents can be used within the range not mentioned.

Further, the thermosetting resin composition of the present invention includes:
Barium sulfate, silicon sulfide, talc, depending on the desired physical properties
Known and commonly used fillers such as clay, bentonite, kaolin, glass fiber, carbon fiber, mica, asbestos, and metal powder; known and commonly used coloring pigments such as phthalocyanine blue, phthalocyanine green, titanium oxide, and carbon black; defoaming Various additives such as an agent, an adhesion promoter or a leveling agent may be added.

Next, a multilayer printed wiring board using the thermosetting resin composition of the present invention or a molded article thereof will be described. (1) Formation of interlayer insulating layer using thermosetting resin composition First, the thermosetting epoxy resin composition of the present invention is screen-printed, curtain-coated, roll-coated, and sprayed on an insulating substrate on which an inner conductor circuit is formed. It is applied using a known method such as a coat and dried. The drying conditions at this time vary depending on the solvent used, but are selected in the range of 60 to 150 ° C. for 5 to 60 minutes. Next, after drying, thermal curing is performed as needed to form an interlayer insulating layer. The thermosetting condition at this time is selected from 130 ° C. to 200 ° C. in the range of 15 to 90 minutes.

(2) Formation of Interlayer Insulating Layer from Molded Thermosetting Epoxy Resin Composition Preparation of Molded Article The resin composition constituting the molded article is used as a component for improving mechanical strength and flexibility. In addition to the component (A) constituting the resin composition of the present invention, a phenoxy resin, a polyacryl resin, a polyimide resin, a polyamideimide resin, a polycyanate resin, a polyester resin, a polyphenylene ether resin, and the like can be blended. These resins can be used in combination of two or more.

Such a thermosetting resin composition of the present invention is diluted with an organic solvent, applied on a supporting film or a supporting metal foil with a film coater or the like, and dried to form a film-shaped molded product or a resin-coated copper foil. Is produced. here,
Examples of the support film include polyethylene, polypropylene, polyester such as polyethylene terephthalate, and polycarbonate. Examples of the supporting metal stay include copper foil. In addition, such a support may be subjected to various pretreatments (mud, corona treatment), and the thickness of the support is generally 5 to 100 μm. In addition, this molded body is adhered and protected by a protective film or the like,
It is desirable to store it in a sheet or roll.

Formation of Interlayer Insulating Layer by Film-Shaped Molding First, the film-shaped molding prepared as described above is
By laminating and laminating the insulating substrate on which the inner conductor circuit is formed under heating and reduced pressure, and further applying pressure, more excellent smoothness of the substrate can be obtained. The laminating conditions include a temperature of 70 to 150 ° C. and a pressure of 1 to 10 kgf / cm ^2.
Is common. Next, after lamination, heat curing is performed as necessary to form an interlayer insulating layer. The thermosetting condition at this time is selected from 130 ° C. to 200 ° C. in the range of 15 to 90 minutes. A method for manufacturing a wiring board using a copper foil with resin will be described later.

(3) Manufacture of Build-up Wiring Board First, through holes and via holes are drilled at predetermined positions of the interlayer insulating layer formed as described above by a drill or a laser. Is treated with a roughening agent to form fine irregularities. At this time, if necessary, physical polishing with a buff may be performed before the roughening agent treatment to stabilize the adhesiveness. The surface of the insulating layer can be roughened by immersing the substrate on which the insulating layer is formed in a solution of an oxidizing agent or the like, or by spraying a solution of the oxidizing agent or the like. Further, it can be carried out by various plasma treatments. These processes may be used in combination. Specific examples of the roughening agent include oxidizing agents such as dichromate, permanganate, ozone, hydrogen peroxide / sulfuric acid, and nitric acid, N-methyl-2-pyrrolidone,
Organic solvents such as N, N-dimethylformamide and methoxypropanol, alkaline aqueous solutions such as sodium hydroxide and potassium hydroxide, and acidic aqueous solutions such as sulfuric acid and hydrochloric acid can be used.

Next, a conductor layer is formed by dry plating such as vapor deposition, sputtering, or ion plating, or wet plating such as electroless or electrolytic plating, and a conductor circuit is formed by pattern etching. The substrate on which the conductor circuit is formed in this manner is subjected to an annealing treatment as necessary, whereby the curing of the thermosetting resin proceeds, and the peel strength of the conductor layer can be further improved. Then, if necessary, these steps are repeated several times to obtain a desired multilayer printed wiring board.

(3 ') Manufacture of build-up wiring board using resin-coated copper foil First, the resin-coated copper foil prepared in (2) above is laminated on a substrate on which an inner layer circuit is formed by a vacuum press. Drilling or laser drilling is performed on the through hole and the via hole, and the inside of the through hole and the via hole is desmeared to form fine irregularities. The method of forming the irregularities is the same as the method of roughening the interlayer insulating layer described above.

Next, a conductor layer is formed by dry plating such as vapor deposition, sputtering, or ion plating, or wet plating such as electroless or electrolytic plating, and a conductor circuit is formed by pattern etching. The substrate on which the conductor circuit is formed in this manner is subjected to an annealing treatment as necessary, whereby the curing of the thermosetting resin proceeds, and the peel strength of the conductor layer can be further improved. Then, if necessary, these steps are repeated several times to obtain a desired multilayer printed wiring board.

[0034]

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but it is needless to say that the present invention is not limited to the following examples. (Examples 1 and 2, Comparative Examples 1 to 3) First, each component was mixed with a solvent and the like in the component composition (parts by mass) shown in Table 1 and uniformly dispersed by a three-roll mill. The viscosity was adjusted to prepare a desired curable resin composition. In preparing such a curable resin composition, Epicoat 100
1. YDCN-704 was previously adjusted to be liquid at room temperature with carbitol acetate, respectively.
Regarding the DICY monoepoxide adduct, dipropylene glycol monoethyl ether was blended at a ratio of 60 parts by weight with respect to 100 parts by weight of the DICY monoepoxide adduct, adjusted to be liquid at room temperature, and adjusted in this way. Each resin solution was used. To uniformly disperse each component, add 0.5 parts by weight of KS-66 as an antifoaming agent to each composition solution and 3 parts by weight of Aerosil # 200 in consideration of printability.
After mixing, kneading was performed by a three-roll kneader. In addition, the curable resin composition has a viscosity (20 Pa · s) at which screen printing can be performed using carbitol acetate.
s). The amounts of DICY and DICY monoepoxide adduct in Table 1 were adjusted so that the amount of active hydrogen in these curing agents was the same as the amount of epoxy groups in the epoxy resin component.

With respect to the curable resin compositions of Examples 1 and 2 and Comparative Examples 1 to 3 thus obtained, printability,
The curability, drilling workability, peel strength and solder heat resistance were evaluated. The evaluation method is as follows. (Printability) Ten test substrates (300
× 300 mm), the curable resin composition was applied by screen printing (150 mesh screen made of PET), and the clogging of the cross portion of the screen plate was visually observed and evaluated. The surface state of the cured coating film after heat curing (150 ° C. × 30 minutes) was visually observed and evaluated. (Curability) With respect to the test substrate on which the cured coating film was formed as described above, the state of warpage due to curing was evaluated by measuring the height of a floating portion with the substrate placed on a flat plate. In addition, the state of the cured coating film surface when the warpage was corrected manually was observed and evaluated with an optical microscope. (Drilling workability) The test substrate on which the cured coating film was formed as described above was drilled, and the state of the coating film in the processed hole was observed and evaluated with an optical microscope. (Peel strength) The test substrate on which the cured coating film was formed as described above was subjected to a surface roughening treatment using a roughening agent. This surface roughening treatment was a method of swelling with a solvent + alkali and then roughening the surface using an oxidizing agent. Next, electroless copper plating and electrolytic copper plating were performed on the roughened surface to form a conductor having a plating thickness of 25 μm, thereby producing a printed wiring board. The peel strength of the printed wiring board created in this way is
The adhesion between the conductor and the insulating material was measured and evaluated in accordance with JIS C6481. (Solder heat resistance) For the printed wiring board prepared as described above, a rosin-based flux was applied to the surface of the conductor, and then floated in a solder bath at 280 ° C. for 30 seconds, and the blister between the conductor and the insulating material was visually observed. And observed and evaluated.

Table 2 shows the results. As is clear from Table 2, in Comparative Examples 2 and 3 using DICY,
In the screen printing method, clogging of the screen was caused, and particles were generated on the surface of the cured coating film, and the warpage of the cured substrate was largely corrected to cause cracks. In addition, in the drilling workability, occurrence of cracks was confirmed at the edge. In this regard, in Examples 1 and 2 according to the resin composition of the present invention, printability, curability, and drilling workability were excellent, and no abnormality as in the comparative example was confirmed. In the evaluation as a printed wiring board,
When Examples 1 and 2 were compared with Comparative Examples 1 and 3, it was confirmed that the peel strength was improved by using the filler component and the rubber component decomposed or dissolved by the roughening agent as essential components. On the other hand, with respect to the solder heat resistance, when Comparative Example 1 and Comparative Example 3 were compared, although the peel strength was the same, swelling occurred in Comparative Example 3 in the solder heat resistance test. This is considered to be the difference in the composition uniformity of the cured coating,
This seems to be due to the use of the DICY monoepoxide adduct dissolved in a diethylene glycol-based or dipropylene glycol-based ether-based solvent. Therefore, it was confirmed that the printed wiring boards evaluated in Examples 1 and 2 had excellent peel strength and solder heat resistance.

[0037]

[Table 1]

[0038]

[Table 2]

[0039]

As described above, according to the present invention, as a thermosetting resin composition for a wiring board used for forming a resin insulating layer, a monoepoxide adduct of dicyandiamide is used in the form of diethylene glycol or dipropylene glycol. Since it is used by dissolving it in an ether-based solvent and liquefied, it is possible to form a uniform coating film with excellent printability and curability, adhesion to the conductor layer, heat resistance, and interlayer insulation reliability (moisture resistance). The present invention can provide a multilayer printed wiring board on which an insulating layer exhibiting excellent characteristics inherent to epoxy resin such as (1) is formed.

[Brief description of the drawings]

FIG. 1 is a diagram showing the results of differential thermal analysis of an epoxy resin composition containing dicyandiamide.

FIG. 2 is a diagram showing the results of differential thermal analysis of an epoxy resin composition containing a monoepoxide adduct of dicyandiamide.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C08K 5/16 C08K 5/16 C08L 15/00 C08L 15/00 63/02 63/02 F term (reference) 4F071 AA12 AA18 AA42 AB17 AB21 AB28 AH13 BA02 BB02 BC02 4J002 AC032 AC102 BG003 CC183 CC193 CC213 CD003 CD021 CD031 CD051 CD121 CK052 DE076 DE086 DE096 DE236 DJ006 FD013 GQ00 4J036 AA02 AB17 AC01 AC02 AC08 AD08 DD03 KA03 DA01 DC03 DC03 DC03 DD03 DD17 DD23 DD32 EE33 EE35 GG15 HH18

Claims (8)

[Claims] (A) an epoxy resin having at least two epoxy groups in one molecule, (B) a rubber component,
(C) A resin composition containing a filler component that is decomposed or dissolved by a roughening agent, and (D) a monoepoxide adduct of dicyandiamide as an epoxy resin curing agent, wherein the monoepoxide adduct of dicyandiamide (D) is: A thermosetting resin composition for a wiring board, wherein the thermosetting resin composition is dissolved in a diethylene glycol-based or dipropylene glycol-based ether-based solvent and uniformly mixed and dispersed in the composition. 2. The epoxy resin (A) is a bisphenol A type epoxy resin having an epoxy equivalent of 400 or more (A1).
And an epoxy resin (A2) having two or more epoxy groups in one molecule having an epoxy equivalent of less than 400,
The weight ratio of the epoxy resin (A1) to the epoxy resin (A2) is 30: 7.
2. The method according to claim 1, wherein the range is from 0 to 90:10.
3. The thermosetting resin composition according to item 1. 3. A rubber component (B) containing 40 parts by weight or less of epoxidized polybutadiene with respect to 100 parts by weight of the epoxy resin (A), and calcium carbonate as a filler component (C) containing the epoxy resin (A). 3. The thermosetting resin composition according to claim 1, wherein the content is 70 parts by weight or less based on 100 parts by weight. 4. The monoepoxide adduct of dicyandiamide (D) is contained in a ratio of 1 to 40 parts by weight in an outer frame amount with respect to 100 parts by weight of an epoxy resin (A). The thermosetting resin composition according to any one of the above. 5. The monoepoxide adduct of dicyandiamide (D) is used in an amount of 10 parts by weight based on 100 parts by weight of the adduct.
The thermosetting resin composition according to any one of claims 1 to 4, wherein the thermosetting resin composition is dissolved in a diethylene glycol-based or dipropylene glycol-based ether-based solvent in a proportion of 0 part by weight or less. 6. A molded article formed by applying the thermosetting resin composition according to any one of claims 1 to 5 on a support film and drying to form a film. 7. A molded article which is formed by applying the thermosetting resin composition according to any one of claims 1 to 5 on a supporting copper foil and drying to form a resin-coated copper foil. 8. A multilayer printed wiring board produced by using the thermosetting resin composition or the molded article according to claim 1.