JPH115826A - Epoxy resin composition for build-up - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition useful as an electric insulating resin for a circuit board such as a multilayer printed wiring board, by including a specific trifunctional epoxy resin, a curing agent, a curing promoter and a leveling agent. SOLUTION: This composition comprises an epoxy resin containing a trifunctional epoxy resin of formula I (R1 to R8 are each independently 1-8C alkyl, H, etc.), a curing agent (especially selected from a polyhydric phenol containing two or more phenolic OHs in one molecule and an aromatic amine compound of formula II containing two or more amine groups in one molecule), a curing promoter (especially an imidazole compound) and a leveling agent (selected from a fluorine-based or a silicone-based surfactants) and optionally 3-30 pts.wt. based on 100 pts.wt. of the epoxy resin solid content of a rubber and 1-300 pts.wt. of an inorganic and/or organic filter and has preferably 10-10,000 cPs viscosity at 25 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition, and more particularly to an epoxy resin composition for build-up useful as an electric insulating resin material for wiring boards such as multilayer printed wiring boards.

[0002]

2. Description of the Related Art Conventionally, as a printed wiring board for electric processing which is processed into a printed wiring board or the like, a prepreg is prepared by impregnating a base material such as a glass cloth with an epoxy resin and drying. And a metal foil such as a copper foil is stacked on one side or both sides as necessary, and is formed by heating and pressing. With respect to such printed wiring boards for electrical use, the tendency of high-density mounting, high integration, high-density electrical wiring, lightness, and shortness has been increasing.

In response to these demands, a new type of build-up multilayer wiring board has recently been receiving attention. In this build-up multilayer wiring board, instead of a prepreg, an electrically insulating resin layer is formed directly on a circuit board using only a resin such as an epoxy resin or a mixture with a filler or the like. Examples of the method for forming the resin layer by the pild-up method include a method of applying a resin with a flow coater, a method of screen printing, and a method of laminating a resin film. In addition, a multilayer wiring board in which a copper foil is preliminarily coated with a resin to be semi-cured and laminated using a resin-added copper foil has been adopted. Although this build-up multilayer wiring board is extremely excellent in terms of lightness, thinness, and miniaturization, it has higher heat resistance, moisture resistance, crack resistance, and heat resistance than conventional multilayer wiring boards using prepregs reinforced with glass fiber or the like. There is a problem that various properties such as workability are inferior, and high performance of the insulating resin is required. Further, when the insulating resin layer between the conductor layers is formed by the coating method, repelling may occur in the coating film formed by the coating, whereby the insulating resin layer having a desired thickness is not formed, and as a multilayer wiring board, There was also a problem that the yield was lowered.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to form an insulating resin layer between conductor layers by a coating method on a multilayer wiring board in which an insulating resin layer is formed directly on a circuit board, that is, a build-up type multilayer wiring board. In this case, an epoxy resin composition for build-up is obtained in which an insulating resin layer having excellent heat resistance, moisture resistance, crack resistance, and workability is obtained without causing repelling in a coating film formed by coating. To provide.

[0005]

The present invention employs the following means to solve the above problems. (1) The epoxy resin composition for build-up of the present invention (hereinafter simply referred to as “epoxy resin composition”) comprises an epoxy resin containing a trifunctional epoxy resin represented by the following formula (a), a curing agent, and a curing agent. An accelerator and a leveling agent are included.

[0006]

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(2) In the epoxy resin composition according to the above (1), the curing agent comprises two or more phenolic O per molecule.
It is at least one selected from the group consisting of a polyfunctional phenol compound having an H group and an aromatic amine compound having two or more amine groups in one molecule represented by the following formula (b). .

[0008]

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(3) In the epoxy resin composition of the above (1) or (2), the curing accelerator is an imidazole compound. (4) In the epoxy resin composition according to any one of (1) to (3), the leveling agent is at least one selected from the group consisting of a fluorine-based surfactant and a silicon-based surfactant. .

(5) The epoxy resin composition according to any one of the above (1) to (4), further comprising a rubber. (6) In the epoxy resin composition of (5), the average particle diameter of the rubber is 0.05 to 10 μm. (7) In the epoxy resin composition of the above (5) or (6), the amount of rubber added is 3 to 30 parts by weight based on 100 parts by weight of the solid content of the epoxy resin.

(8) The epoxy resin composition according to any one of the above (1) to (7), further comprising an inorganic filler. (9) In the epoxy resin composition of (8), the inorganic filler is a particle having an average particle diameter of 0.01 to 50 μm. (10) In the epoxy resin composition of the above (8) or (9), the amount of the inorganic filler added is 1
It is 1 to 300 parts by weight with respect to 00 parts by weight.

(11) The epoxy resin composition according to any one of the above (1) to (10), further comprising an organic filler. (12) In the epoxy resin composition of (11), the amount of the organic filler to be added is 1 to 300 parts by weight based on 100 parts by weight of the solid content of the epoxy resin. (13) In the epoxy resin composition according to any one of (1) to (12), the viscosity at 25 ° C is 10 to 10
000 cps.

[0013]

Since the epoxy resin composition of the present invention contains the above-mentioned trifunctional epoxy resin as an epoxy resin, an insulating resin layer having excellent heat resistance, moisture resistance, crack resistance and workability can be obtained. Here, “excellent in heat resistance” means that the glass transition temperature is high. In addition, since it also contains a leveling agent, repelling is less likely to occur in a coating film obtained by using the epoxy resin composition of the present invention, and the thickness of the coating film is less likely to be partially reduced.

When the epoxy resin composition of the present invention also contains rubber, it is possible to obtain an insulating resin layer that is less likely to crack when subjected to an impact such as a thermal shock. When the epoxy resin composition of the present invention also contains an inorganic filler and / or an organic filler, viscosity increase and thixotropy are imparted, and coatability is improved.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The object to which the epoxy resin composition of the present invention is used is, for example, an electric printed multilayer wiring board, and is particularly used as an electric insulating resin layer of a build-up type electric printed multilayer wiring board. Is done. This epoxy resin composition has excellent heat resistance, moisture resistance, crack resistance,
It is useful as having workability.

In the present invention, in order to obtain an insulating resin layer having excellent heat resistance, moisture resistance, crack resistance and workability, an epoxy resin containing the trifunctional epoxy resin represented by the above formula (a) as an essential component is used. I do. In addition to the trifunctional epoxy resin, a bisphenol A type epoxy resin, a nopolak type epoxy resin, or a brominated compound thereof may be used in combination, if necessary. Alternatively, a mixture in which the trifunctional epoxy, bisphenol A or a brominated compound thereof, and a bisphenol A type epoxy resin or a brominated compound thereof may be used in advance may be used. The content ratio of the trifunctional epoxy resin represented by the formula (a) is based on the entire epoxy resin.
It is preferably 20 to 80% by weight. If the content is less than 20% by weight, the effect of enhancing heat resistance and moisture resistance at high temperatures is small. On the other hand, if it exceeds 80% by weight, it becomes difficult to obtain flame retardancy.

The curing agent used in the present invention is not particularly limited, but dicyandiamide may have 2 per molecule.
Examples include a polyfunctional phenol compound having at least two phenolic OH groups and an aromatic amine compound having a plurality of amine groups in the molecule. Regarding the blending amount of the curing agent, the equivalent of the curing agent is preferably 0.2 to 1.2 equivalents per equivalent of the epoxy group. Examples of the polyfunctional phenol compound include low molecular weight compounds such as bisphenol A, bisphenol F, bisphenol S, polyvinyl phenol, β-naphthol, phenol novolak resin, cresol novolak resin, bisphenol A type novolak resin, and alkylphenol novolak resin. , Triphenylmethane-type trifunctional novolak resins synthesized from phenol and hydroxybenzaldehyde, and further, their bromides, etc., and these phenolic compounds or resins may be used in combination. Can also. Examples of the aromatic amine compound include a compound represented by the above formula (b). R _{1 to} R ₈ in the formula (b) are each selected from an alkyl group having 1 to 8 carbon atoms (for example, a lower alkyl group such as methyl, ethyl, propyl, and isopropyl), a halogen atom or a hydrogen atom, They can be the same or different.

As the curing agent, among the above, it is preferable to use a polyfunctional phenol compound and / or an aromatic amine compound without blending dicyandiamide. This is because the addition of dicyandiamide causes dicyandiamide to precipitate during drying and curing, resulting in reduced workability and film formability, as well as reduced long-term insulation reliability and crack resistance.

Examples of the curing accelerator used in the present invention include an imidazole compound and a tertiary amine compound.
The blending amount may be determined as appropriate. In the case where an insulating layer is formed, repelling may occur due to dirt on a surface to be coated. When such repelling occurs, the resin film thickness at that portion becomes thin, and it becomes difficult to secure insulation. Repelling can be improved by lowering the surface tension of the solution to be applied. Therefore, in the present invention, a leveling agent is added to the electric insulating resin composition. As the leveling agent, for example, a fluorine-based surfactant, a silicone-based surfactant, or the like is used. One type of leveling agent can be used alone, or two or more types of leveling agents can be used in combination. The fluorosurfactant is not particularly limited, and examples thereof include perfluoroalkylalkoxylates, which are nonionic (nonionic) surfactants. Examples of the silicone surfactant include, but are not particularly limited to, alkyl-modified polysiloxane, aralkyl-modified polysiloxane, and polyester-modified polysiloxane. The amount of the leveling agent is not particularly limited.
0 parts by weight, for example, 0.01 to 1.0 parts by weight,
Preferably it is 0.05 to 0.5 parts by weight. If the amount is less than 0.01 part by weight, the effect of preventing repelling from occurring in the coating film is poor, and if the amount is more than 1.0 part by weight, the effect is not increased. Because.

In the present invention, when rubber is included in the epoxy resin composition, internal stress is generated due to solvent evaporation and curing shrinkage, impact strength of the epoxy resin is reduced due to high crosslinking density, and impact such as thermal shock is caused. This is desirable because an insulating resin layer in which cracks are less likely to occur when subjected to heat can be obtained. The introduction of the rubber component has an effect of suppressing cracks generated due to low impact strength of the cured product of the epoxy resin. Especially for build-up type printed circuit boards,
Since the insulating resin layer is not reinforced by a glass cloth base or the like, cracks are easily generated by thermal stress or mechanical stress. Therefore, introduction of a rubber component capable of suppressing cracks is useful. Rubber types include SBR (styrene / butadiene rubber), NBR (nitrile rubber), CTBN, AT
BN, IR (polyisoprene), BR (polybutadiene), silicone rubber and the like can be used. The average particle diameter of the rubber is preferably about 0.05 to 10 μm in consideration of the above-described resin crack, other heat resistance, hygroscopicity, and the like. If the thickness is less than 0.05 μm, the effect of suppressing the generation of cracks due to impact is small, and if it exceeds 10 μm, there is a problem that heat resistance is deteriorated. As for the compounding amount (content) of the rubber, the rubber is preferably about 3 to 30 parts by weight based on 100 parts by weight of the epoxy resin solids in the epoxy resin composition. If the amount is less than 3 parts by weight, the effect of suppressing the generation of cracks due to impact is small, and if it exceeds 30 parts by weight, there is a problem that heat resistance is deteriorated. Among various rubbers, crosslinked CTBN can be dispersed microscopically and evenly in the epoxy resin composition, so that after the epoxy resin is hardened, little aggregation occurs, which is effective in suppressing cracks. Useful.

The epoxy resin composition of the present invention can be used when forming an insulating resin layer by a coating method such as flow coating or screen printing.
It is preferable that the viscosity at 25 ° C. is 10 to 10,000 cps in order to form a desired thickness of the insulating resin layer.
The viscosity can be adjusted by adding a solvent. It is preferable to select a solvent that does not react with the epoxy resin, the curing agent, or the curing accelerator as the solvent to be used. For example, methyl ethyl ketone, acetone, ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methanol, ethanol, toluene, xylene, DM
F, DMAc and the like can be exemplified, and a plurality of these can be used in combination.

When forming an insulating layer, bubbles are a problem other than the occurrence of repelling. The generation of bubbles may make it difficult to ensure insulation at that portion. For this reason, it is preferable to add an antifoaming agent. The defoaming agent is not particularly limited, and for example, a polyether-modified polysiloxane can be used. The amount of the defoaming agent is not particularly limited, but is preferably 0.01 to 1.0 part by weight based on 100 parts by weight of the epoxy resin. 0.
If the amount is less than 01 parts by weight, the defoaming effect is poor, and if the amount exceeds 1.0 part by weight, the effect is not increased, and the compounding is useless, resulting in a decrease in heat resistance and phase separation.

The addition of the inorganic filler to the epoxy resin composition is first performed for improving the coating property. Addition of an inorganic filler imparts viscosity and thixotropy, and improves the uniformity of the film thickness. In addition to the above, there are objects such as improvement of heat resistance, water resistance, moisture absorption resistance, mechanical strength, reduction of linear expansion coefficient, and flame retardancy. Examples of the inorganic filler include calcium carbonate, silica, synthetic silica, kaolin clay (aluminum silicate), titanium oxide, barium sulfate,
Zinc oxide, aluminum hydroxide, alumina, magnesium hydroxide, talc, mica, glass flake, hydrotalside, wollastonite, potassium titanate, magnesium sulfate, sepiolite, zonolite, aluminum borate, glass beads, ballas balloon, magnesia Etc. can be exemplified. The inorganic fillers of the above examples can be used alone or in combination of two or more. When the inorganic filler is in the form of particles, the average particle diameter is not particularly limited, but is, for example, 0.01 to 50 μm. If it is less than 0.01 μm, dispersion in the epoxy resin becomes difficult, and if it is more than 50 μm, it may be difficult to secure insulation. The blending amount is not particularly limited, but is, for example, 1 to 300 parts by weight based on 100 parts by weight of the solid content of the epoxy resin. If the amount is less than 1 part by weight, it is difficult to exhibit performance such as applicability, and if it exceeds 300 parts by weight, the viscosity is remarkably increased, and it becomes difficult to prepare a coating, and the application performance may be reduced.

The addition of the organic filler to the epoxy resin is first performed to improve the laser workability. In recent years, an inner via hole (IVH) for conducting connection between conductors of a multilayer printed wiring board is processed by laser. As the laser, a carbon dioxide laser is mainly used. In the case of a carbon dioxide gas laser, it is difficult to form IVH because a difference occurs in the laser processing speed between the inorganic compound and the organic compound. Therefore, an object is to improve the laser workability by using an organic filler instead of the inorganic filler as a filler. Further, an organic filler capable of improving heat resistance, water resistance, moisture absorption resistance, mechanical strength, and a reduction in linear expansion coefficient is also added. Examples of the organic filler include aromatic polyimide (aramid), polyoxybenzoyl ester, and polyethylene beads. The organic fillers of the above examples can be used alone or in combination of two or more. The compounding amount and the average particle diameter when the organic filler is in the form of particles are the same as those in the case of the above-mentioned inorganic filler, and the description thereof will be omitted.

According to the present invention, in order to obtain an insulating resin layer having a large mechanical strength at normal temperature and heat, a small coefficient of thermal expansion, a warp and an interface of the substrate and excellent crack resistance, an aspect ratio of 5 is required. As described above, preferably 10 or more fibrous fillers can be used. Here, the aspect ratio is a ratio L / D of the average fiber diameter (diameter) D of the fibrous filler and the average fiber length L. When the aspect ratio is less than 5, improvement in mechanical strength cannot be expected much, and the amount of filler added increases significantly. The fibrous filler is not particularly limited as long as it is made of an insulator. For example, in the case of an inorganic filler (inorganic compound), calcium carbonate, magnesium hydroxide, wollastonite, potassium titanate, magnesium sulfate, sepiolite, zonolite , Aluminum borate, glass fiber and the like. Organic fillers (organic compounds) include polyoxybenzoyl (PO
B), polyoxynaphthoyl (PON), aramid fiber and the like. The above examples may be used alone or in combination of two or more. When the average fiber length of the fibrous filler, particularly the fibrous inorganic filler is 10 μm or less, the inner via hole (IVH) by laser is used.
Workability is improved. If the fibrous filler exceeds 10 μm, the fibrous filler protrudes from the inner wall of the laser IVH, resulting in poor shape and poor plating coverage. In other words, electrical continuity between the layers cannot be obtained, or disconnection occurs in a thermal shock test. From the viewpoint of further improving IVH processability, the average fiber length of the fibrous filler, particularly the fibrous inorganic filler, is preferably 10 μm or less.

The amount of the fibrous filler added is 10 to 60%
The effect appears in the range. If it is less than 10%, a decrease in the coefficient of thermal expansion and an increase in mechanical strength cannot be expected much. Also, 6
If it exceeds 0%, the effect will not be improved any more, and it will be excessively added. From the viewpoint of effectively reducing the coefficient of thermal expansion or improving the mechanical strength, the preferred amount of the fibrous filler is 15% based on the total weight of the insulating resin and the fibrous filler. ~ 45%.

When the fibrous filler is an organic filler,
Laser IVH processability is improved. In recent years, an inner via hole (IVH) for conducting connection between conductor layers of a multilayer printed wiring board is processed by a laser. As the laser, a carbon dioxide laser is mainly used. In the case of a carbon dioxide laser, there is a difference in laser processing speed between an inorganic compound and an organic compound. When an inorganic filler is used as the fibrous filler, the filler protrudes from the IVH inner wall as described above. The above problem can be avoided by a method such as optimizing laser processing conditions or shortening the fiber length of the fibrous filler, but it is very difficult to control due to lack of stability and the like. By using an organic filler as the fibrous filler, laser workability can be improved. In case of organic filler, average fiber length is 10μ
Even if the length is longer than m, the laser workability can be improved.

In order to maximize the effect of the fibrous filler, the coupling treatment at the filler interface, particularly at the inorganic filler interface, is very important. Examples of the coupling agent include a silane coupling agent, a titanate coupling agent, and an aluminate coupling agent. In the case of an organic filler, for example, a plasma-treated filler is preferable.

When the fibrous filler is used in combination with a particulate inorganic filler and / or an organic filler, the anisotropy of physical properties specific to the fibrous filler can be improved. As the particles, for example, an average particle size of 0.1
〜50 μm is used. If the average particle size of the particles is smaller than the range, anisotropy may remain, and if the average particle size is larger than the range, insulating properties and laser processability may be reduced. The addition amount of the particles is not particularly limited, but is, for example, 20 to 120% by weight with respect to the fibrous filler,
Preferably it is 30 to 70% by weight. If the added amount of the particles is less than the range, improvement in anisotropy may not be obtained, and if it exceeds the range, no further improvement in anisotropy is observed and excessive addition may be caused.

The epoxy resin composition of the present invention may contain components other than those described above, if necessary.

[0031]

Next, the present invention will be described based on examples.
The present invention is not limited to the following examples. (Examples 1 to 6, Comparative Examples 1 and 2) Using a 0.8 mm thick epoxy resin glass cloth laminate (manufactured by Matsushita Electric Works Co., Ltd., product number R-1700) in which copper foil having a thickness of 18 μm was arranged on one side,
A copper conductor circuit was formed by etching to obtain an inner layer circuit board. The inner layer circuit board was etched with an organic acid-based etchant (manufactured by MEC Corporation, part number CZ-15452) with an etching depth of 4
μm soft etching was performed to roughen the surface of the copper conductor circuit. Next, on the roughened surface, as shown in Tables 1 and 2, by flow coating or screen printing,
The epoxy resin composition prepared with the composition (parts by weight) shown in Table 2 was applied to form a coating film. Tables 1 and 2 show the viscosities of the prepared epoxy resin compositions at 25 ° C. Further, the appearance of the formed coating film was visually inspected, and the presence or absence of repelling was evaluated. The results are shown in Tables 1 and 2. In addition, the presence of repelling was evaluated by visual evaluation, and it was determined that repelling having a diameter of 1 mm (where the coating was crater-like and the thickness was small) occurred. After forming the coating film as described above, a test sample was formed by heating at 110 ° C. for 30 minutes, then at 150 ° C. for 20 minutes, and further heating at 170 ° C. for 90 minutes in a drier to form a 50 μm thick insulating resin layer. Was prepared. Using the prepared test sample, the glass transition temperature (Tg) of the insulating resin layer, the solder heat resistance after moisture absorption, and the number of cycles until the occurrence of a resin crack in a thermal shock test were evaluated by the following test methods. Are shown in Tables 1 and 2.

Test method for glass transition temperature of insulating resin layer:
It is measured by DSC at a heating rate of 20 ° C./min. Test method for solder heat resistance after moisture absorption: A test sample on which an insulating resin layer is formed is subjected to a moisture absorption treatment at a temperature of 40 ° C. and a relative humidity of 90%, and then subjected to a test of being immersed in a solder at 260 ° C. for 20 seconds, followed by solder immersion The moisture absorption treatment time until blistering occurs later is used as an evaluation scale.

Test Method for Crack Generation in Thermal Shock Test: A test sample on which an insulating resin layer was formed was subjected to a thermal cycle shock of [-65 ° C. × 5 minutes + 150 ° C. × 5 minutes]. The number of cycles until a crack occurs in the insulating resin layer is used as an evaluation scale. The following materials were used as the materials shown in Tables 1 and 2 used for preparing the epoxy resin composition. -Trifunctional epoxy resin: an epoxy resin containing the component represented by the formula (a) as a main component, manufactured by Mitsui Petrochemical Industry Co., Ltd., product number VG3101, epoxy equivalent 210 g / Eq-Brominated epoxy resin: the formula (a) An epoxy resin using bisphenol A diglycidyl ether and tetrabromobisphenol A as raw materials, manufactured by Mitsui Petrochemical Co., Ltd., product number VF2803, epoxy equivalent
420g / eq, bromine content 19% by weight ・ Brominated bisphenol A type epoxy resin: manufactured by Toto Kasei Co., Ltd., product number YDB-400, epoxy equivalent 400g / eq,
Bromine content 48% by weight ・ Brominated bisphenol A type epoxy resin: manufactured by Toto Kasei Co., Ltd., product number YDB-500, epoxy equivalent 500g / eq,
Bromine content 20% by weightAromatic amine: bis (4-amino-2-chloro-3
, 5 diethylphenyl) methane, manufactured by Nippon Kayaku Co., Ltd., trade name C-BS300, NH equivalent 95 ・ Aromatic amine: 2,2 ', 3,3'-tetrachloro-4,4'-diaminodiphenylmethane, Ihara Made by Chemical Co., Ltd., trade name TCDAM, NH equivalent: 84 ・ CTBN: made by Nippon Synthetic Rubber Co., Ltd., trade name XER-191, average particle size 0 07 μm ・ SBR: average particle size 1 μm ・ Curing accelerator: manufactured by Shikoku Chemicals Co., Ltd., trade name 2E4MZ-CN ・ Fluorine surfactant: perfluoroalkyl alkoxylate, manufactured by Sumitomo 3M Limited, trade name: FC-430

[0034]

[Table 1]

[0035]

[Table 2]

From the results of Tables 1 and 2, it can be seen that in Examples, the glass transition temperature was higher than that of Comparative Example 1, the solder heat resistance after moisture absorption was good, and cracks hardly occurred in the thermal shock test. confirmed. On the other hand, in Comparative Example 2 in which the leveling agent was not blended, repelling occurred in the coating film. Further, it was confirmed that cracks were less likely to occur in the thermal shock test in Examples 4 to 6 containing rubber than in Examples 1 to 3 not having rubber. (Examples 7 to 20, Comparative Examples 3 to 7) Using an epoxy resin glass substrate laminate (manufactured by Matsushita Electric Works Co., Ltd., product number R-1700) having a thickness of 0.8 mm and a copper foil having a thickness of 18 μm arranged on one side, An organic acid-based etching solution (manufactured by MEC Corporation,
(Part number CZ-8100), 2 μm soft etching was performed to roughen the copper surface. An epoxy resin composition having the component composition shown in Tables 3 to 5 was applied on the roughened copper surface. 30 minutes at 110 ° C, 50 at 150 ° C
Then, the test sample was heated and cured at 170 ° C. for 90 minutes in a box drier to form a 50 μm thick insulating resin layer. Tables 3 to 5 show the viscosities of the prepared epoxy resin compositions at 25 ° C.

The glass transition temperature (Tg), the moisture absorption rate, the solder heat resistance after moisture absorption, the occurrence of resin cracks in the thermal shock test, and the repelling of the resin after the coating film formation were obtained for the test samples prepared in the above Examples and Comparative Examples. The presence / absence and laser workability were evaluated. The glass transition temperature, the solder heat resistance after moisture absorption, and the occurrence of resin cracks in a thermal shock test were measured in the same manner as described above.

The moisture absorption was calculated by performing the treatment under the condition of 85 ° C./85%/200 hours and measuring the weight. The presence or absence of resin repelling after the formation of the coating film was evaluated by visual inspection after the formation of the coating film. The laser processability can be determined by observing the IVH cross section after laser processing.
Judgment was made based on the quality of the shape and the roundness with plating.

Laser condition: Laser processing equipment: 505GT manufactured by Mitsubishi Electric Corporation was used. Processing energy 3m
J × 2 shot After laser processing, plating was applied. The plating thickness was 20 μm with respect to the surface to be plated. The evaluation was performed by cross-section observation. As the IVH shape, a mortar-shaped or rectangular-shaped one was regarded as good. The turning property with plating relating to the conductivity is good when the plating thickness of the IVH side wall is 12 μm or more.
Less than μm was regarded as defective. In addition, the conduction was evaluated using a 3000-hole pattern, and a sample having conduction (10 Ω or less) was evaluated as good. Finally, these were comprehensively evaluated, and those with conduction were evaluated as ○, and those with no conduction were evaluated as x. With respect to the above-mentioned ○, the one having good IVH shape and plating circumstance was evaluated as ◎. Otherwise, it was marked as ○.

The following epoxy resins, curing agents, curing accelerators and repelling agents were used in addition to those described above. The phenol novolak type epoxy resin is YDCN-704 manufactured by Toto Kasei Co., Ltd. and has an epoxy equivalent of 220.
g / eq. The polyfunctional phenol compound was Tris-PA (trisphenols novolak resin) manufactured by Mitsui Petrochemical Co., Ltd. and had an OH equivalent of 142.

The 4,4'-diamino-3,3'-diethyl 5,5'-dimethyldiphenylmethane curing agent, which is an aromatic amine compound, was obtained from IUREA CHEMICAL INDUSTRIES CO., LTD. there were. The dicyandiamide used was manufactured by Nippon Carbide Industry Co., Ltd. -BYK-310 (polyether-modified dimethylsiloxane) manufactured by BYK Japan KK was used as the silicone surfactant. -As the solvent, propylene glycol monomethyl ether acetate (PGM-AC) manufactured by Kuraray Co., Ltd.
It was used.

As a solvent, dimethylformamide (DMF) manufactured by Mitsubishi Gas Chemical Company, Inc. was used.・ Cross-linked type CTBN is XER- manufactured by JSR Corporation.
91 was used. The average particle size is 0.07 μm.・ NBR is Hycar ATB manufactured by Ube Industries, Ltd.
N was used. The molecular weight is 3400. -Barium sulfate was used as the inorganic filler.
Using B-34 manufactured by Sakai Chemical Industry Co., Ltd., the average particle size is
0.3 μm. -Fibrous aluminum borate was used as the inorganic filler. Only those having a fiber length of 10 μm or less among YS3A manufactured by Shikoku Chemical Industry Co., Ltd. (that is, those having an average fiber length of 10 μm or less) were used. Average fiber diameter is 1μm
It is. -Aramid fiber was used as the organic filler. The average fiber length is 1 mm, and the average fiber diameter is 12 μm. -The organic filler is poly (p-oxybenzoyl)
(POB) was used. Average fiber length is 50-100 μm,
The average fiber diameter is from 1 to 1.5 μm.

[0043]

[Table 3]

[0044]

[Table 4]

[0045]

[Table 5]

As can be seen from Tables 3 to 5, it can be seen that those of the examples have high glass transition temperatures, high solder heat resistance after moisture absorption, and excellent heat resistance. It can be seen that the moisture absorption rate is low, and no resin crack is generated in the thermal shock test.
In the examples, a leveling agent is blended, and since there is no repelling, it can be seen that the coating film forming property is extremely improved. Impact was further improved by introducing rubber and adding inorganic and organic fillers. Further, the laser workability is slightly inferior when an inorganic fibrous material is added, but greatly improved when an organic fibrous material is used.
As described above, it was found that the example was extremely excellent in practical use.

[0047]

Since the epoxy resin composition of the present invention according to any one of the first to thirteenth aspects contains a Sannomiya epoxy resin as an epoxy resin, the epoxy resin composition of the present invention is used to directly form an insulating resin layer on a circuit board. When used for multilayer wiring boards, so-called build-up type multilayer wiring boards, heat resistance, moisture resistance,
An insulating resin layer having excellent crack resistance and workability can be obtained. In addition, since the film contains a leveling agent, repelling hardly occurs in the resulting coating film.

The epoxy resin composition of the invention according to claim 2 further improves processability and film formability, and also improves long-term insulation reliability, crack resistance and the like. Since the epoxy resin composition according to the third aspect of the present invention contains an imidazole compound as a curing accelerator, the epoxy resin composition further has effects of lowering the activation energy of the reaction, lowering the curing temperature, and shortening the curing time. Also improve.

In the epoxy resin composition according to the fourth aspect of the present invention, repelling can be further eliminated, and the problem that the thickness of the resin is reduced and the insulating property is reduced is less likely to occur. Since the epoxy resin composition of the invention according to claims 5 to 7 also contains rubber, in addition to the above-described effects, an insulating resin layer which is less likely to crack when subjected to a shock such as a thermal shock is obtained. It also has the effect that it can be done.

Since the epoxy resin composition of the invention according to claims 8 to 10 also contains an inorganic filler, in addition to the above-mentioned effects, uniformity of film thickness, heat resistance, water resistance, moisture absorption resistance, The mechanical strength is more improved, the coefficient of linear expansion is lower,
Alternatively, an effect that flame retardancy can be imparted is also exerted. Since the epoxy resin composition of the invention according to claims 11 to 12 also contains an organic filler, in addition to the above-described effects, laser workability, heat resistance, water resistance, moisture absorption resistance, and mechanical strength are further improved. However, the linear expansion coefficient can be further reduced.

Since the epoxy resin composition of the invention according to claim 13 has a viscosity at 25 ° C. of 10 to 10,000 cps, in addition to the above effects, it is possible to form an insulating resin layer having a desired thickness. It also has an effect.

Continued on the front page (72) Inventor Shinichi Ikeya 1048 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Works, Ltd. (72) Inventor Shoichi Fujimori 1048 Kadoma Kadoma, Kadoma City, Osaka Matsushita Electric Works Co., Ltd. (72) Inventor Isao Hirata 1048 Kadoma Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd. (72) Inventor Kiyoaki Ihara 1048 Kadoma Kadoma, Kadoma-shi, Osaka Pref. Address Matsushita Electric Works Co., Ltd. (72) Inventor Satoru Ogawa 1048 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Works Co., Ltd. (72) Inventor Yoshihiro Nakagawa 1048 Kazuma Kadoma City, Osaka Prefecture Matsushita Electric Works Co., Ltd. (72) Invention Person Masayuki Ishihara 1048 Kadoma, Kazuma, Osaka Prefecture Matsushita Electric Works, Ltd.

Claims (13)

[Claims] 1. An epoxy resin composition for build-up comprising an epoxy resin comprising a trifunctional epoxy resin represented by the following formula (a), a curing agent, a curing accelerator, and a leveling agent. Embedded image 2. The method according to claim 1, wherein the curing agent is a polyfunctional phenol compound having two or more phenolic OH groups in one molecule, and two or more amine groups in one molecule represented by the following formula (b). The epoxy resin composition for build-up according to claim 1, which is at least one selected from the group consisting of aromatic amine compounds having the following formula: Embedded image 3. The epoxy resin composition for build-up according to claim 1, wherein the curing accelerator is an imidazole compound. 4. The build-up according to claim 1, wherein the leveling agent is at least one selected from the group consisting of a fluorine-based surfactant and a silicon-based surfactant. Epoxy resin composition. 5. The epoxy resin composition for build-up according to claim 1, further comprising a rubber. 6. The rubber has an average particle size of 0.05 to 10
The epoxy resin composition for build-up according to claim 5, which has a thickness of µm. 7. The epoxy resin composition for build-up according to claim 5, wherein the amount of the rubber added is 3 to 30 parts by weight based on 100 parts by weight of the solid content of the epoxy resin. 8. The epoxy resin composition for build-up according to claim 1, further comprising an inorganic filler. 9. The method according to claim 1, wherein the inorganic filler has an average particle size of 0.0
The epoxy resin composition for build-up according to claim 8, which is a particle of 1 to 50 m. 10. The epoxy resin composition for build-up according to claim 8, wherein the amount of the inorganic filler is 1 to 300 parts by weight based on 100 parts by weight of the solid content of the epoxy resin. 11. The epoxy resin composition for build-up according to claim 1, further comprising an organic filler. 12. The epoxy resin composition for build-up according to claim 11, wherein the amount of the organic filler is 1 to 300 parts by weight based on 100 parts by weight of the solid content of the epoxy resin. 13. A viscosity at 25 ° C. of 10 to 10,000.
The epoxy resin composition for build-up according to any one of claims 1 to 12, which is cps.