WO2015155982A1 - Resin composition for printed wiring board, prepreg, metal-clad laminate, and printed wiring board - Google Patents

Abstract

　A resin composition for a printed wiring board contains an inorganic filler and a resin component that contains a thermoset resin. The inorganic filler contains crushed silica measuring 0.1 m²/g-15 m²/g in specific surface area, and molybdenum compound particles having at least a molybdenum compound on the surface layer. The crushed silica content is 10-150 parts by mass to 100 parts by mass of the resin component.

Description

Resin composition for printed wiring board, prepreg, metal-clad laminate, printed wiring board

The present invention relates to a resin composition for printed wiring boards, a prepreg, and a metal-clad laminate used as a material for printed wiring boards, and also relates to a printed wiring board manufactured using these.

Printed wiring boards are widely used in various fields such as electronic devices, communication devices, and computers. In recent years, especially in small portable devices such as portable communication terminals and notebook PCs, multifunction, high performance, thinning and downsizing are rapidly progressing. For this reason, electronic components such as semiconductor packages mounted on such devices are also becoming thinner and smaller. Along with this, printed wiring boards used to mount these electronic components are also required to have high performance such as miniaturization, multilayering, thinning, and mechanical characteristics of wiring patterns.

As the printed wiring board becomes thinner in this way, it is caused by a difference in coefficient of thermal expansion (hereinafter referred to as CTE) between a conductor layer and an insulating layer for forming a circuit, or a difference in CTE between a mounted component and an insulating layer. However, warping of the printed wiring board has been regarded as a problem. As a method for preventing warpage, it is known that reducing the CTE of the insulating layer is effective. Therefore, technical development for reducing the CTE of the insulating material constituting the insulating layer has been performed. In the case of a multilayer printed wiring board, the layers are electrically connected by forming a via hole or the like in the insulating layer. In order to ensure the reliability of this interlayer electrical connection, it is required to reduce the CTE in the thickness direction.

In order to reduce the CTE of the insulating layer, it is known to add an inorganic filler to the resin composition constituting the insulating layer. Silica is used as such an inorganic filler.

For example, Patent Document 1 proposes an epoxy resin composition for a prepreg containing a predetermined phosphorus compound, bifunctional epoxy resin, polyfunctional epoxy resin, curing agent, inorganic filler, and molybdenum compound as essential components. Examples of inorganic fillers include magnesium hydroxide, silica, and talc. And the printed wiring board manufactured using this epoxy resin composition for prepregs has excellent glass transition temperature (Tg), flame retardancy, heat resistance, and thermal rigidity, and excellent hole position accuracy. ing.

Patent Document 2 proposes a thermosetting resin composition containing a thermosetting resin, silica, and a molybdenum compound, and having a silica content of 20% by volume to 60% by volume. A printed wiring board produced using this resin composition is excellent in drilling workability, and its insulating layer has good electrical insulation and low thermal expansion.

Patent Document 3 discloses a resin composition containing a reaction product obtained by reacting at least a part of hydroxyl groups of polyphenylene ether with an epoxy group of an epoxy compound, a cyanate ester compound, and an organometallic salt. Yes. With this configuration, it is possible to produce a cured product that achieves an excellent glass transition temperature (Tg) while maintaining the excellent dielectric properties of polyphenylene ether.

International Publication No. 2011/118584 JP 2012-23248 A JP 2014-152283 A

The present invention provides a resin composition for a printed wiring board that can achieve a low thermal linear expansion coefficient and can achieve good drill workability and moldability while meeting the demand for cost reduction, and uses the same. Prepregs, metal-clad laminates, and printed wiring boards.

The 1st resin composition for printed wiring boards which concerns on this invention contains the resin component containing a thermosetting resin, and an inorganic filler. The inorganic filler includes crushed silica having a specific surface area of 0.1 m ² / g or more and 15 m ² / g or less, and molybdenum compound particles having a molybdenum compound in at least a surface layer portion. The content of crushed silica is in the range of 10 to 150 parts by mass with respect to 100 parts by mass of the resin component.

In the first resin composition for a printed wiring board of the present invention, crushed silica having a predetermined specific surface area is used even though relatively inexpensive crushed silica is used. Moreover, the content is also limited to the specific range. Molybdenum compound particles are used in combination. With this configuration, the thermal expansion coefficient of the printed wiring board, which is the final form of the cured product, can be reduced, and good drillability can be realized.

The second resin composition for a printed wiring board according to the present invention includes a resin component and an inorganic filler. The resin component includes the following (a) and (b), and the inorganic filler includes the following (c) and (d).
(A) Prereacted product obtained by reacting polyphenylene ether with an epoxy compound having an epoxy group (b) Cyanate ester compound (c) Surface-treated hydrophobic silica particles (d) At least a molybdenum compound Molybdenum compound particles in the surface layer portion In the second printed wiring board resin composition of the present invention, the glass transition temperature and the dielectric properties are stable and excellent, and can be cured with good drillability and formability. Can make things.

The prepreg according to the present invention can be obtained by impregnating a base material with the resin composition for printed wiring board and semi-curing it.

The metal-clad laminate according to the present invention can be obtained by stacking a metal foil on the prepreg, and integrating by heating and pressing.

The printed wiring board according to the present invention can be obtained by removing a part of the metal foil of the metal-clad laminate and forming a conductor pattern.

FIG. 1 is a schematic cross-sectional view of a prepreg according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of a metal-clad laminate according to an embodiment of the present invention. FIG. 3 is a schematic cross-sectional view of a printed wiring board according to the embodiment of the present invention.

(Embodiment 1)
Prior to the description of the first embodiment of the present invention, problems in the conventional configuration will be described. In a resin composition for a printed wiring board, silica is generally used as an inorganic filler added to reduce CTE. By using silica, the cured product exhibits good electrical characteristics and heat resistance. As silica, spherical silica and crushed silica are known.

On the other hand, when the insulating layer contains a large amount of an inorganic filler, there is a problem in workability such that the drill blade is easily worn when the printed wiring board is drilled to form a through hole. When spherical silica is used, this drillability is relatively good. Patent Document 2 also describes that fused spherical silica is preferable. Thus, it is thought that it is contributing to the improvement of drill workability and moldability that the shape of each silica particle is spherical. Moreover, in order to improve drill workability, it is also known that it is effective to add a molybdenum compound to a resin composition as shown in Patent Document 1 and Patent Document 2.

In recent years, there has been a demand in the market to reduce the cost of printed wiring board materials while maintaining various characteristics at a high level while realizing a low CTE in the insulating layer. The fused spherical silica is produced, for example, through processing steps such as melting and spheroidizing a pulverized silica powder in a flame. Therefore, fused spherical silica is more expensive than crushed silica. However, using crushed silica as an alternative to spherical silica is economically advantageous, but drill workability and moldability may be greatly reduced.

In order to solve the above problems, the inventors of the present application first tried to use pulverized silica as an inorganic filler and further add a molybdenum compound. However, a resin composition in which spherical silica is simply replaced with crushed silica as it is cannot sufficiently improve the drilling processability and moldability. Then, it discovered that the said subject could be solved by using the crushing silica which has a specific specific surface area, and restrict | limiting the content to a specific range.

Hereinafter, Embodiment 1 of the present invention will be described. The printed wiring board resin composition according to the present embodiment (hereinafter also simply referred to as “resin composition”) contains a resin component and an inorganic filler.

The resin component includes a thermosetting resin, and includes a curing agent and a curing accelerator as necessary.

Examples of the thermosetting resin include epoxy resins, phenol resins, imide resins, cyanate ester resins, isocyanate resins, modified polyphenylene ether resins, benzoxazine resins, and oxetane resins. In particular, as the epoxy resin, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy compound, bisphenol A novolak type epoxy compound, biphenyl aralkyl type epoxy resin, naphthalene ring-containing epoxy compound And dicyclopentadiene (DCPD) type epoxy resin. Only one of these thermosetting resins may be used, or two or more of them may be used.

The curing agent is not particularly limited as long as it can react with the thermosetting resin to form a crosslinked structure. For example, bifunctional or higher polyfunctional phenol compounds, polyfunctional amine compounds, acid anhydride compounds, vinyl group-containing compounds, low molecular weight polyphenylene ether compounds, dicyandiamide, and triallyl isocyanate can be exemplified.

Examples of the curing accelerator include organic acid metal salts such as imidazole compounds, amine compounds, thiol compounds, and metal soaps. As a hardening accelerator, only 1 type of these may be used and 2 or more types may be used together.

The resin component may further contain other resin compounds such as a thermoplastic resin, a flame retardant, a colorant, a coupling agent, and the like as necessary.

The inorganic filler includes molybdenum compound particles and crushed silica having a specific surface area within a range of 0.1 m ² / g to 15 m ² / g. The specific surface area of the crushed silica is preferably 9 m ² / g or more and 15 m ² / g or less.

The crushed silica is prepared, for example, by pulverizing fused silica or crystalline silica mined as ore. When the specific surface area of the crushed silica is 0.1 m ² / g or more, when a laminate such as a metal-clad laminate is manufactured using the resin composition, the drillability of the laminate is improved. As described above, it is generally known that when crushed silica is used, drill workability is significantly reduced, such as when the drill blade is easily worn when drilling a laminated plate or the like, compared to when spherical silica is used. ing. However, by using crushed silica having a specific surface area of 0.1 m ² / g or more together with molybdenum compound particles, wear of the drill blade is greatly improved. On the other hand, when crushed silica having a specific surface area of less than 0.1 m ² / g is used, it cannot be expected to sufficiently improve the drill workability even when used with molybdenum compound particles. On the other hand, when the specific surface area of the crushed silica is 15 m ² / g or less, thickening of the varnish of the resin composition is suppressed. Moreover, the increase in melt viscosity at the time of thermoforming is also suppressed, and the resin fluidity falls within a suitable range. Therefore, the moldability at the time of manufacturing a laminated board becomes favorable. As a result, it is possible to prevent the prepreg from being difficult to manufacture and to prevent voids (cavities) from remaining in the insulating layer of the laminate. The specific surface area can be measured by the BET method.

Crushed silica is contained in the resin composition within a range of 10 parts by mass or more and 150 parts by mass or less with respect to 100 parts by mass of the resin component. Preferably they are 10 mass parts or more and 100 mass parts or less. When the crushed silica is less than 10 parts by mass, the degree to which the crushed silica contributes to the reduction in CTE becomes too small. Therefore, in order to make CTE sufficiently small, it is necessary to add a large amount of other inorganic fillers such as spherical silica. That is, the significance of including crushed silica is substantially lost. On the other hand, when the crushed silica exceeds 150 parts by mass, it is necessary to use a large amount of molybdenum compound particles in order to sufficiently improve the drill workability. In that case, heat resistance may be reduced. On the other hand, if the amount of molybdenum compound particles used is suppressed, drill workability may not be sufficiently improved.

The combination is not limited as long as the specific surface area and content of the crushed silica are within the range, but particularly when the specific surface area of the crushed silica is in the range of 9 m ² / g or more and 15 m ² / g or less, the inclusion of the crushed silica The amount is preferably within a range of 10 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the resin component. When the specific surface area of crushed silica increases, the melt viscosity of the resin composition during molding tends to increase. Therefore, by suppressing the content of crushed silica, the fluidity of the resin composition is ensured and the moldability is improved.

Molybdenum compound particles are inorganic particles having at least a molybdenum compound in the surface layer portion. When molybdenum compound particles are used together with crushed silica, the molybdenum compound functions as a lubricant. Therefore, wear of the drill due to crushed silica is suppressed, and drill workability is improved. The molybdenum compound particles may be composed entirely of the molybdenum compound or may be particles in which the molybdenum compound is supported or coated on the surface of a carrier formed of an inorganic material other than the molybdenum compound.

In molybdenum compound particles, it is considered that the molybdenum compound present in the surface layer mainly acts to suppress drill wear. Therefore, in order to obtain an effect of improving the drill workability with a small amount of molybdenum compound, it is preferable to use particles having a molybdenum compound on the surface of a carrier formed of another inorganic material, as in the latter case. In general, the specific gravity of the molybdenum compound is larger than that of an inorganic filler such as silica, and the specific gravity difference with the resin component is large. Therefore, from the viewpoint of dispersibility in the resin composition, it is preferable to use particles having a molybdenum compound on the surface of a carrier formed of another inorganic material. As the inorganic material used as the carrier, talc, aluminum hydroxide, boehmite, magnesium hydroxide, silica, etc., which are usually used as inorganic fillers for laminates, can be suitably used. The average particle size of the carrier is preferably 0.05 μm or more. Such molybdenum compound particles are available as commercial products, and examples thereof include KEGGARD manufactured by Sherwin Williams.

Examples of the molybdenum compound constituting the molybdenum compound particles include molybdenum oxide, molybdate compound, and other molybdenum compounds. An example of molybdenum oxide is molybdenum trioxide. Examples of molybdate compounds include zinc molybdate, calcium molybdate, magnesium molybdate, ammonium molybdate, barium molybdate, sodium molybdate, potassium molybdate, phosphomolybdic acid, ammonium phosphomolybdate, sodium phosphomolybdate, silica Molybdic acid is mentioned. Examples of other molybdenum compounds include molybdenum boride, molybdenum disilicide, molybdenum nitride, and molybdenum carbide. These may be used alone or in combination of two or more. Among these, zinc molybdate (ZnMoO ₄ ), calcium molybdate (CaMoO ₄ ), and magnesium molybdate (MgMoO ₄ ) are preferable from the viewpoints of chemical stability, moisture resistance, and insulation. Only one of these may be used, two may be used in combination, or all three may be used.

The content of the molybdenum compound particles is preferably within a range of 0.1% by volume or more and 10% by volume or less with respect to 100% by volume of the total amount of the inorganic filler. If the content of the molybdenum compound particles is 0.1% by volume or more, it can sufficiently function as a lubricant and improve the drillability of the laminate. If content of a molybdenum compound particle is 10 volume% or less, the influence on the heat resistance of a laminated board and copper foil peel strength can be suppressed. In addition, since the molybdenum compound has low oil absorption, if the content of the molybdenum compound particles is within the above range, the practical resin fluidity during molding or the like is not adversely affected.

The molybdenum compound particles contain a molybdenum compound, and the total content of the molybdenum compound in the resin composition is 0.05 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the resin component. It is preferable to be within the range. If the content of the molybdenum compound in the resin composition is less than 0.05 parts by mass, there is a possibility that sufficient drill workability improvement effect cannot be obtained. Moreover, when the total content of the molybdenum compound exceeds 5 parts by mass, the heat resistance of the laminated board may be reduced.

In addition, from the viewpoint of reducing CTE and improving drillability and moldability, the content of the inorganic filler in the resin composition is 15 parts by mass or more and 400 parts by mass or less with respect to 100 parts by mass of the resin component. It is preferable to be within the range.

The inorganic filler may contain other fillers other than the crushed silica and molybdenum compound particles. That is, by adding other fillers, it is possible to further reduce the CTE in addition to the CTE reduction effect by the crushed silica. Moreover, it is possible to impart properties such as flame retardancy and thermal conductivity that cannot be sufficiently obtained with crushed silica alone. Other fillers can be appropriately selected from known fillers according to the purpose and are not particularly limited. However, a filler having a relatively low hardness that is difficult to reduce drill workability is preferable. Specific examples include spherical silica, aluminum hydroxide, magnesium hydroxide, aluminum silicate, magnesium silicate, talc, clay, mica and the like.

Among these, it is preferable to use spherical silica as the other filler. If spherical silica is used as another filler, all fillers other than the molybdenum compound particles in the inorganic filler can be used as the silica component. In particular, since the upper limit of the content of crushed silica is 150 parts by mass, when the silica component is used as an inorganic filler in an amount of more than 150 parts by mass with respect to 100 parts by mass of the resin component, the remainder exceeding 150 parts by mass Spherical silica may be used as the silica component.

Thus, even if spherical silica is used in addition to crushed silica and molybdenum compound particles, since crushed silica is relatively inexpensive compared to spherical silica, it is still less than when all inorganic fillers are spherical silica. There is cost merit. Moreover, since spherical silica is a shape which does not put a burden on a drill blade, compared with the case where crushing silica is used exceeding said upper limit (150 mass parts), there is no possibility that drill workability may fall large.

Next, a method for preparing the resin composition will be described. The resin composition should be prepared as a resin varnish by preparing resin components, inorganic fillers, and other components to be blended as necessary, respectively, mixing them in a solvent, further stirring and mixing them. Can do. The resin composition includes a thermosetting resin, a curing agent, and the like, and the inorganic filler includes crushed silica and molybdenum compound particles. Under the present circumstances, the resin varnish which mix | blended only the resin component except the inorganic filler may be prepared beforehand as a base resin, and an inorganic filler may be mix | blended with this base resin. As the solvent, for example, ethers such as ethylene glycol monomethyl ether, acetone, methyl ethyl ketone (MEK), dimethylformamide, benzene, toluene and the like can be used.

Next, the prepreg 10 according to the present embodiment will be described with reference to FIG. FIG. 1 is a cross-sectional view of the prepreg 10. The prepreg 10 is obtained by impregnating a base material 4A such as a glass cloth with the varnish of the resin composition obtained as described above, and then drying by heating at 110 to 140 ° C. to remove the solvent in the varnish. It can be produced by semi-curing the product. Therefore, the prepreg 10 includes the base material 4A and the resin composition 2A that is impregnated into the base material 4A and semi-cured. At this time, it is good to adjust so that content of the resin composition in a prepreg may become the range of 30 mass% or more and 80 mass% or less with respect to the prepreg whole quantity.

Next, the metal-clad laminate 20 according to the present embodiment will be described with reference to FIG. FIG. 2 is a cross-sectional view of the metal-clad laminate 20. The metal-clad laminate 20 can be manufactured by superimposing a metal foil 14 such as a copper foil on the prepreg 10 obtained as described above, heating and pressing, and integrating them. Therefore, the metal-clad laminate 20 includes the insulating layer 12 that is a cured product of the prepreg 10 and the metal foil 14 that is laminated on the insulating layer 12. In addition, the metal foil 14 may be piled up on both surfaces of one prepreg 10, and may be heated and pressed to form a metal-clad laminate. Alternatively, a metal-clad laminate may be formed by stacking metal foils 14 on one or both surfaces of a plurality of prepregs 10 that are stacked and heating and pressing. The heating and pressing conditions are, for example, 140 to 200 ° C., 0.5 to 5.0 MPa, and 40 to 240 minutes.

Next, the printed wiring board 30 according to the present embodiment will be described with reference to FIG. FIG. 3 is a cross-sectional view of the printed wiring board 30. The printed wiring board 30 can be manufactured by forming a conductor pattern 16 by removing a part of the metal foil 14 of the metal-clad laminate 20 by etching using a subtractive method or the like. Therefore, the printed wiring board 30 includes the insulating layer 12 that is a cured product of the prepreg 10 and the conductor pattern 16 formed on the insulating layer 12.

When the prepreg 10 and the metal foil 14 are further stacked on the metal-clad laminate 20 shown in FIG. 2 and integrated by heating and press-molding as described above, a conductive pattern 16 is formed. In some cases, it is necessary to connect between a plurality of layers in which the is formed. For this purpose, a hole is made in the insulating layer 12 by drilling to form a through hole or a blind via hole. Since the insulating layer 12 in which the hole is drilled is a cured product of the prepreg 10 (resin composition), the drill workability is good, and wear of the drill can be suppressed. In addition, since the insulating layer 12 is formed of a cured product of the prepreg 10, the insulating layer 12 can be molded well and is less likely to cause scumming. Moreover, the insulating layer 12 has a high heat resistance and a low coefficient of thermal expansion.

Also, a multilayer printed wiring board can be manufactured by preparing a printed wiring board as a core material (inner layer material) and laminating and molding the prepreg 10 thereon. In this case, after the conductor pattern (inner layer pattern) of the core material is roughened by black oxidation or the like, the metal foil 14 is superimposed on the surface of the core material via the prepreg 10, and this laminate is heated and pressed. Mold. The heating and pressing conditions at this time are, for example, 140 to 200 ° C., 0.5 to 5.0 MPa, and 40 to 240 minutes. The core material may be manufactured using the prepreg 10. Next, drilling and desmearing are performed. Thereafter, a conductor pattern (outer layer pattern) is formed using a subtractive method. In addition, a through hole or a blind via hole is formed by plating the inner wall of the hole. A multilayer printed wiring board can be manufactured by such a procedure. The number of layers of the printed wiring board is not particularly limited.

As described above, the printed wiring board resin composition according to the present embodiment contains, together with the molybdenum compound, crushed silica having a predetermined specific surface area in a specific range. Thereby, in the metal-clad laminate and the printed wiring board manufactured using the resin composition for printed wiring boards, the thermal expansion coefficient of the insulating layer is reduced despite using relatively inexpensive crushed silica. be able to. In addition, it is possible to achieve good drillability when performing drilling.

Hereinafter, the effects of the present embodiment will be further described with specific examples.

[1] Manufacturing procedure of laminated board for evaluation (1) Resin composition According to the blending composition shown in Tables 1 to 4, the resin component and the inorganic filler are blended and further diluted with a solvent. To prepare a varnish of the resin composition. As the solvent, MEK is used in the following base resin 1, and toluene is used in the following base resin 2. Each material is as follows.

<Resin component (base resin 1)>
Phenol novolac type epoxy resin (“N-770” manufactured by DIC Corporation)
Cresol novolac type phenolic resin (“KA-1165” manufactured by DIC Corporation)
2-Ethyl-4-methylimidazole (“2E4MZ” manufactured by Shikoku Kasei Kogyo Co., Ltd.)

<Resin component (base resin 2)>
Cyanate ester resin (Lonza "BADCy", 2,2-bis (4-cyanatophenyl) propane)
Dicyclopentadiene type epoxy resin (“HP7200” manufactured by DIC Corporation)
Polyphenylene ether (PPE) resin (SABIC Innovative Plastics "SA90")
Metal soap (zinc octoate)

<Inorganic filler>
Silica particles are selected from the following five types.
Spherical silica (Co. Admatechs made "SC2500-SEJ", a specific gravity of 2.2g / ^cm 3)
Crushed silica 1 (“AS-1 SSA” manufactured by Tatsumori Co., Ltd., specific surface area 20 m ² / g, specific gravity 2.2 g / cm ³ )
Crushed silica 2 ("MC3000" manufactured by Admatechs Co., Ltd., specific surface area 15 m ² / g, specific gravity 2.2 g / cm ³ )
Fractured silica 3 ("MC6000" manufactured by Admatechs Co., Ltd., specific surface area 10 m ² / g, specific gravity 2.2 g / cm ³ )
Crushed silica 4 ("Megasil 525" manufactured by Sibelco, specific surface area 2.2 m ² / g, specific gravity 2.2 g / cm ³ )
As the molybdenum compound particles, zinc molybdate-treated talc “KEMGARD911C” manufactured by Sherwin Williams is used. The amount of zinc molybdate is 17% by mass, the specific gravity is 2.8 g / cm ³ , and the average particle size is 3.0 μm.

(2) Prepreg As a base material, a glass base material (WEA116ES136, thickness 0.1 μm) manufactured by Nitto Boseki Co., Ltd. is used. The base material is impregnated with a varnish of the resin composition at room temperature, and then dried by heating at 150 to 160 ° C. Thereby, the prepreg is manufactured by removing the solvent in the varnish and semi-curing the resin composition. The resin content (resin amount) in the prepreg is 56% by mass.

(3) Laminated plate Six prepregs (300 mm × 450 mm) are stacked, and copper foil (made by Mitsui Mining & Smelting Co., Ltd., thickness 35 μm) is further stacked on both sides as a metal foil for 90 minutes at 200 ° C. and 3 MPa. Heat-press molding. The laminated board for evaluation (thickness 0.8 mm) is manufactured in such a procedure.

[2] Evaluation and Results of Laminate (1) Scrap after Molding After removing the copper foil on both sides of the 0.8 mm thick laminate by etching, the presence or absence of scum was confirmed by visual inspection.

(2) Drill wear rate: Laminated four 0.8mm thick laminates, 0.15mm aluminum plate for entry board, 0.15mm bake plate for backup board, with 0.3mm diameter drill A through hole is formed by drilling 5000 hits. Then, the drill wear rate after drilling is measured.

As a drill, “NHU L020W” manufactured by Union Tool Co., Ltd. is used. The number of rotations of the drill when drilling is 160000 r. p. m, the feed rate of the drill is 3.2 m / min.

(3) Thermal expansion coefficient (CTE)
After removing the copper foil on both sides of the 0.8 mm thick laminate by etching, the temperature is lower than the glass transition temperature (Tg) by the TMA method (Thermal mechanical analysis method) based on IPC TM650 2.4.24. The thermal expansion coefficient in the plate thickness direction is measured.

(4) T-288 heat resistance After removing the copper foil on both sides of the 0.8 mm thick laminate by etching, the decomposition start time of the cured product of the resin composition when it is kept at 288 ° C. is obtained.

The above evaluation results are shown in (Table 3) and (Table 4).

As is clear from (Table 3) and (Table 4), the laminated plates of samples EA to EE are comparable to the case of using spherical silica (samples CA, CB, CK) even though crushed silica is used. The better the drilling processability, the formability, the heat resistance, and the lower the thermal expansion coefficient.

In particular, when comparing sample EA and sample CE, sample EB and sample CF, sample EC and sample CG, and sample EE and sample CL, it is good to use the predetermined crushed silica defined in this embodiment together with molybdenum compound particles. It can be seen that excellent drillability can be realized.

Also, from the comparison between the sample ED and the sample CH, it can be seen that if the content of the molybdenum compound particles is too large, the heat resistance is greatly reduced.

Also, the laminated plates of samples EF to EJ using both crushed silica and spherical silica also show excellent drillability, formability, heat resistance, and a low coefficient of thermal expansion.

In addition, in samples CC and CD using crushed silica having a large specific surface area, it is considered that the resin fluidity at the time of molding was lowered, and smoldering after molding was observed.

In samples CI and CJ, the content of crushed silica exceeds 150 parts by mass. In the sample CI, the drill wear rate is reduced by increasing the content of the molybdenum compound particles. However, the heat resistance (T-288) is greatly reduced. On the other hand, in the sample CJ in which the content of molybdenum compound particles is refrained, the drill wear rate exceeds 70%, although the heat resistance is not greatly reduced.

(Embodiment 2)
Prior to the description of the second embodiment of the present invention, problems in the conventional configuration will be described. Even when the resin composition disclosed in Patent Document 3 is used, the glass transition temperature and dielectric loss tangent of the cured product may be significantly reduced. For example, when silica particles that have absorbed moisture are used, the glass transition temperature and dielectric properties of the cured product decrease with time. On the other hand, when new silica particles (dry silica particles) are used, the glass transition temperature and dielectric loss tangent of the cured product are excellent.

In the present embodiment, a resin composition for a printed wiring board that is stable and excellent in glass transition temperature and dielectric properties and that can realize good drill processability and moldability will be described based on the above knowledge. .

The resin composition for printed wiring boards (hereinafter referred to as resin composition) according to the present embodiment is blended with a resin component including the following (a) and (b), and an inorganic filler including the following (c) and (d) Prepared.
(A) Prereacted product obtained by reacting polyphenylene ether with an epoxy compound having an epoxy group (b) Cyanate ester compound (c) Surface-treated hydrophobic silica particles (d) At least a molybdenum compound Molybdenum compound particles in the surface layer portion That is, this resin composition is prepared by first reacting a polyphenylene ether and an epoxy compound to form a prereacted product (a), and then further adding a cyanate ester compound (b) and a hydrophobic silica. It is prepared by blending particles (c) and molybdenum compound particles (d). Thus, the cured product of the resin composition rather than the resin composition obtained without forming the preliminary reaction product by previously reacting the polyphenylene ether and the epoxy compound to form the preliminary reaction product (a). The glass transition temperature of (hereinafter, cured product) can be increased. Furthermore, since the cured product uses the resin component as a base resin, it is excellent in dielectric characteristics such as dielectric constant and dielectric loss tangent.

The amount of water brought into the resin composition is preferably less than 0.1%, more preferably 0.07% by mass or less, based on the total mass of the resin composition. When the amount of moisture brought into the resin composition is within the above range, the varnish gel time of the resin composition is unlikely to be shortened. When the varnish gel time is short, when the resin composition is cured, the resin composition cannot be sufficiently heated, and a large amount of volatile components remain in the cured product. Therefore, there exists a possibility that the glass transition temperature of hardened | cured material may fall large. The amount of moisture brought into the resin composition is mainly due to the moisture absorbed by the silica particles. Therefore, when the surface treatment is not performed on the silica particles, a relatively large amount of water is mixed into the resin composition.

If a large amount of moisture is brought into the resin composition, the varnish gel time for the resin composition will be significantly shortened. This phenomenon is peculiar to the resin composition containing the preliminary reaction product (a), the cyanate ester compound (b), the hydrophobic silica particles (c), and the molybdenum compound particles (d). For example, a resin composition prepared by polymerizing polyphenylene ether, epoxy compound, cyanate ester compound (b), hydrophobic silica particles (c) and molybdenum compound particles (d) without using the pre-reacted product (a) Does not show this phenomenon.

The reason why the varnish gel time is shortened when the amount of moisture brought into the resin composition is large is presumed to be because the trimerization reaction of the cyanate ester caused by the cyanate ester compound (b) is promoted. That is, when the amount of moisture brought into the resin composition is large, the cyanate ester compound (b) and water are likely to react with each other, and carbamate is likely to be generated. The active hydrogen in the carbamate, together with the molybdenum compound, greatly promotes the trimerization reaction of the cyanate ester resulting from the cyanate ester compound (b), thereby generating a triazine ring. It is presumed that this triazine ring functions as a curing agent and the resin composition is easily gelled.

The varnish gel time of the resin composition needs to be 120 seconds or more, preferably 120 to 240 seconds, and more preferably 150 to 210 seconds. In this Embodiment, varnish gel time is defined as time until 2.5 ml of the varnish of the obtained resin composition gelatinizes on a 200 degreeC cure plate.

The adsorbed water content of the silica particles can be measured by the Karl Fischer method (JIS K0113: 2005, coulometric titration method). The amount of moisture brought into the resin composition can be calculated by the following calculation formula.
Moisture amount brought into resin composition = (water amount contained in silica (Karl Fischer measurement value%) × silica addition amount / total amount of resin composition) × 100
Next, the resin component will be described. The resin component includes a pre-reacted product (a) and a cyanate ester compound (b). First, the preliminary reaction product (a) will be described. The preliminary reaction product (a) is prepared by reacting the polyphenylene ether (a-1) with an epoxy compound (a-2) having an epoxy group.

The polyphenylene ether (a-1) preferably has an average of 1.5 to 2 hydroxyl groups in one molecule. Having an average of 1.5 to 2 hydroxyl groups in one molecule means that the average number of hydroxyl groups per molecule (average number of hydroxyl groups) is 1.5 to 2. When the average number of hydroxyl groups is 1.5 or more, the three-dimensional crosslinking is caused by reacting with the epoxy group of the epoxy compound (a-2), so that the adhesion during curing is improved. Further, when the average number of hydroxyl groups is 2 or less, it is considered that there is no possibility of gelation during the preliminary reaction.

The average number of hydroxyl groups of polyphenylene ether (a-1) can be determined from the standard value of the polyphenylene ether product used. Examples of the average number of hydroxyl groups of polyphenylene ether (a-1) include the average value of hydroxyl groups per molecule of all the polyphenylene ethers present in 1 mol of polyphenylene ether.

The number average molecular weight (Mn) of the polyphenylene ether (a-1) is preferably 800 or more and 2000 or less. If the number average molecular weight is 800 or more, the dielectric properties, heat resistance, and high glass transition temperature of the cured product can be secured. In addition, if the number average molecular weight is 2000 or less, even if a pre-reacted product reacted with an epoxy resin having relatively few epoxy groups is contained, resin flow or phase separation may occur, or moldability may be deteriorated. Can be suppressed.

A polyphenylene ether having a number average molecular weight of 800 or more and 2000 or less can be directly prepared by, for example, a polymerization reaction. Alternatively, polyphenylene ether having a number average molecular weight of 2000 or more may be prepared by redistribution reaction in a solvent in the presence of a phenolic compound and a radical initiator. The number average molecular weight (Mn) of polyphenylene ether (a-1) can be measured using, for example, gel permeation chromatography.

Examples of the polyphenylene ether (a-1) include poly (2,6-dimethyl-1,4-phenylene oxide), 2,6-dimethylphenol, and at least one of a bifunctional phenol and a trifunctional phenol. And polyphenylene ether having a molecular structure synthesized in (1). Among these, the latter polyphenylene ether having a molecular structure synthesized with 2,6-dimethylphenol and at least one of bifunctional phenol and trifunctional phenol is preferable. Examples of the bifunctional phenol include tetramethylbisphenol A.

The epoxy compound (a-2) preferably has an average of 2 to 2.3 epoxy groups in one molecule. When the average number of epoxy groups is within this range, a pre-reacted product with polyphenylene ether (a-1) can be satisfactorily produced while maintaining the heat resistance of the cured product.

Examples of the epoxy compound (a-2) include dicyclopentadiene (DCPD) type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, naphthalene type epoxy resin, and biphenyl type epoxy resin. Can be mentioned. These may be used alone or in combination of two or more. Among these, a DCPD type epoxy resin is particularly preferable from the viewpoint of improving dielectric characteristics. Further, bisphenol A type epoxy resin and bisphenol F type epoxy resin are preferable from the viewpoint of good compatibility with polyphenylene ether. In addition, although it is preferable not to contain a halogenated epoxy resin from a heat resistant viewpoint, you may mix | blend as needed if it is a range which does not impair the effect of this invention.

The average number of epoxy groups of the epoxy compound (a-2) can be determined from the standard value of the epoxy resin product used. Specific examples of the number of epoxy groups in the epoxy resin include an average value of epoxy groups per molecule of all epoxy resins present in 1 mol of the epoxy resin.

The solubility of the epoxy compound (a-2) in toluene is preferably 10% by mass or more at 25 ° C. As a result, the compatibility between the epoxy compound (a-2) and the polyphenylene ether (a-1) becomes relatively high, and the epoxy compound (a-2) easily reacts uniformly with the polyphenylene ether (a-1). Conceivable. As a result, the heat resistance of the cured product is sufficiently increased without impairing the excellent dielectric properties of polyphenylene ether (a-1).

The preliminary reaction product (a) is prepared, for example, by the following reaction. First, the polyphenylene ether (a-1) and the epoxy compound (a-2) are weighed so as to have a predetermined ratio, and these are weighed in an organic solvent having a solid concentration of about 50 to 70% for about 10 to 60 minutes. Stir to mix. The mixture is heated at 80 to 110 ° C. for 2 to 12 hours to react polyphenylene ether (a-1) with epoxy compound (a-2). Thereby, the preliminary reaction product (a) is prepared. The organic solvent is not particularly limited as long as it dissolves polyphenylene ether (a-1) and epoxy compound (a-2) and does not inhibit these reactions. For example, toluene can be used.

There is a preferred range for the ratio of the polyphenylene ether (a-1) to the epoxy compound (a-2). When this ratio is expressed as the molar ratio of the epoxy group of the epoxy compound (a-2) to the hydroxyl group of the polyphenylene ether (a-1) (epoxy group / hydroxyl group), the preferred range is 3 or more and 6 or less, more preferably It is about 3.5 or more and 5.5 or less. When the molar ratio is in the above range, both ends of the polyphenylene ether (a-1) can be efficiently capped with epoxy groups. Furthermore, when the viscosity of a preliminary reaction material (a) falls, the viscosity of the varnish and prepreg mentioned later falls, and productivity improves.

When the polyphenylene ether (a-1) and the epoxy compound (a-2) are reacted, a catalyst may coexist. The catalyst is not particularly limited as long as it can promote the reaction between the hydroxyl group of polyphenylene ether (a-1) and the epoxy group of epoxy compound (a-2). Examples thereof include metal salts of organic acids, tertiary amines, imidazoles, and organic phosphines. Examples of metal salts of organic acids include metal salts of organic acids such as octanoic acid, stearic acid, acetylacetonate, naphthenic acid, and salicylic acid, such as Zn, Cu, and Fe. Examples of the tertiary amine include 1,8-diazabicyclo [5.4.0] undecene-7 (DBU), triethylamine, triethanolamine and the like. Examples of imidazoles include 2-ethyl-4-imidazole (2E4MZ) and 4-methylimidazole. Examples of organic phosphines include triphenylphosphine (TPP), tributylphosphine, tetraphenylphosphonium / tetraphenylborate, and the like. These may be used alone or in combination of two or more. Among these, imidazoles, particularly 2-ethyl-4-imidazole, is particularly preferable because the reaction time can be shortened and polymerization between epoxy resins (self-polymerization of epoxy resins) can be suppressed. The content of the catalyst is preferably 0.05 parts by mass or more and 1 part by mass or less with respect to 100 parts by mass in total of the polyphenylene ether (a-1) and the epoxy compound (a-2). If the catalyst content is within the above range, the reaction between the hydroxyl group of polyphenylene ether (a-1) and the epoxy group of epoxy compound (a-2) does not take time, and the reaction is easily controlled. , Difficult to gel.

The solid content concentration during the reaction is preferably about 50 to 70% in view of reaction efficiency and viscosity (manufacturability).

Next, the cyanate ester compound (b) will be described. The cyanate ester compound (b) preferably has an average number of cyanate groups per molecule (average number of cyanate groups) of 2 or more. Thereby, the heat resistance of hardened | cured material can be improved. Here, the average number of cyanate groups is an average value of cyanate groups per all cyanate resin molecules present in 1 mol of the cyanate resin used as the cyanate ester compound (b). The average number of cyanate groups can be determined from the standard value of the cyanate resin product.

Examples of the cyanate ester compound (b) include 2,2-bis (4-cyanatephenyl) propane (bisphenol A type cyanate resin), bis (3,5-dimethyl-4-cyanatephenyl) methane, 2,2- Aromatic cyanate ester compounds such as bis (4-cyanatephenyl) ethane or derivatives thereof. These may be used alone or in combination of two or more.

The resin composition preferably further contains an epoxy compound (e). Like the epoxy compound (a-2), the epoxy compound (e) preferably has an average of 2 or more and 2.3 or less epoxy groups in one molecule. Examples of the epoxy compound (e) include DCPD type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin and the like. These may be used alone or in combination of two or more. In this case, the epoxy compound (e) may be the same as or different from the epoxy compound (a-2). As the epoxy compound (e), a DCPD type epoxy resin is preferable from the viewpoint of improving dielectric properties.

In addition to the epoxy compounds having an average of 2 or more and 2.3 or less epoxy groups per molecule, among polyfunctional epoxy compounds such as a cresol novolac epoxy resin, an average of 2.3 per molecule A compound having more epoxy groups can also be used.

When the resin composition contains a DCPD type epoxy resin as the epoxy compound (a-2) and / or the epoxy compound (e), the DCPD type with respect to the total mass of the epoxy compound (a-2) and the epoxy compound (e) It is preferable that 50 mass% or more of the epoxy compound is contained. Thereby, an insulating material having better dielectric properties can be manufactured.

A preferable blending ratio of the resin component is 100 parts by mass of the total amount of the polyphenylene ether (a-1), the epoxy compound (a-2), the cyanate ester compound (b) and the epoxy compound (e) (epoxy compound (e For example, the following ranges are included. 10 parts by mass or more and 40 parts by mass or less of polyphenylene ether (a-1), and 20 parts by mass or more and 60 parts by mass or less of the cyanate ester compound (b ) Is 20 parts by mass or more and 40 parts by mass or less. When the compounding of the epoxy compound (e) is 0, the epoxy compound (a-2) is preferably 20 parts by mass or more and 60 parts by mass or less. It is considered that such a blend makes it possible to achieve both excellent dielectric properties, heat resistance and adhesion (adhesion) of the cured product.

The resin composition may further contain a halogen flame retardant or a non-halogen flame retardant. Thereby, the flame retardance of hardened | cured material increases. When a halogen-based flame retardant is used, flame retardancy can be imparted to the cured product, the glass transition temperature of the cured product is unlikely to decrease, and heat resistance is not significantly reduced. When a halogen-based flame retardant is used, flame retardancy can be easily imparted to the cured product even when a DCPD type epoxy resin that is difficult to impart flame retardancy is used.

It is preferable that the halogen-based flame retardant is not dissolved but dispersed in the varnish described below. Examples of the halogen flame retardant include ethylenedipentabromobenzene, ethylenebistetrabromoimide, decabromodiphenyl oxide, and tetradecabromodiphenoxybenzene having a melting point of 300 ° C. or higher. By using such a halogen-based flame retardant, it is considered that elimination of halogen at high temperatures can be suppressed, and a decrease in heat resistance can be suppressed.

It is preferable from the viewpoint of flame retardancy and heat resistance that the halogen-based flame retardant is contained at a blending ratio such that the halogen concentration in the total amount of the resin component is about 5 to 30% by mass.

Next, the inorganic filler will be described. The inorganic filler includes hydrophobic silica particles (c) subjected to surface treatment and molybdenum compound particles (d) having a molybdenum compound in at least a surface layer portion. First, the hydrophobic silica particles (c) will be described.

Hydrophobic silica particles (c) are difficult to absorb moisture even under high temperature or high humidity environment. Therefore, even if the hydrophobic silica particles (c) that have been left (stored) at room temperature for a long time are used as the material of the resin composition, moisture is hardly brought into the resin composition. As a result, the varnish gel time equivalent to that of the silica particles in the dry state can be maintained. That is, depending on the storage state of the silica particles, the glass transition temperature and dielectric properties of the cured product are unlikely to deteriorate with time, and the glass transition temperature and dielectric properties are stable and excellent. Here, the dry silica particles mean silica particles having a water content of less than 0.1% measured by the Karl Fischer method.

As the treatment agent for performing the surface treatment, for example, a known treatment agent such as a silane coupling agent or silicone oil can be used. Examples of silane coupling agents include silane couplings such as β-ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, hexamethyldisilazane, and dimethyldichlorosilane. An agent can be mentioned. Hydrophobic silica particles (c) are available as commercial products, for example, “Megasil 525RCS” manufactured by Sibelco Japan Co., Ltd.

Examples of the silica particles constituting the hydrophobic silica particles (c) include spherical silica and crushed silica. Among them, spherical silica or crushed silica having a specific surface area of 0.1 m ² / g or more and 15 m ² / g or less as described in Embodiment 1 in that the drillability of the cured product is further improved. Is preferred. From the economical viewpoint, crushed silica having a specific surface area of 0.1 m ² / g or more and 15 m ² / g or less is more preferable.

When the specific surface area of the crushed silica is 0.1 m ² / g or more and used together with the molybdenum compound particles (d), a laminate such as a metal-clad laminate is produced using the resin composition. The drilling workability of the plate can be improved. On the other hand, when the specific surface area of the crushed silica is 15 m ² / g or less, the thickening of the varnish of the resin composition is suppressed, and the increase of the melt viscosity at the time of thermoforming is also suppressed, and the resin flowability in a suitable range Thus, the moldability at the time of producing the laminated plate is improved. These effects are the same as those of the first embodiment.

As described above, the features of the present embodiment can be combined with the first embodiment. In that case, the resin component includes a prereacted product obtained by reacting polyphenylene ether and an epoxy compound having an epoxy group, and a cyanate ester compound. The inorganic filler has a specific surface area within a range of 0.1 m ² / g or more and 15 m ² / g or less, a crushed silica whose surface has been subjected to a hydrophobic treatment, and a molybdenum compound having at least a surface portion of a molybdenum compound. Particles. This makes it possible to produce a cured product that is stable and excellent in glass transition temperature and dielectric properties, and that can realize good drill workability and formability at a high level.

The preferred range of the content of the hydrophobic silica particles (c) is 10 parts by mass or more and 200 parts by mass or less, more preferably 10 parts by mass or more and 150 parts by mass or less, and further preferably 100 parts by mass of the resin component. 30 parts by mass or more and 100 parts by mass or less. When the content of the hydrophobic silica particles (c) is within the above range, the thermal linear expansion coefficient of the cured product can be reduced.

When the silica particles constituting the hydrophobic silica particles (c) are crushed silica, the content of the hydrophobic silica particles (c) is preferably 10 parts by mass or more and 150 parts by mass with respect to 100 parts by mass of the resin component. Hereinafter, it is more preferably 20 parts by mass or more and 100 parts by mass or less. The reason is the same as in the first embodiment.

The combination is not limited as long as the specific surface area and content of the crushed silica are within the above ranges, but when the specific surface area of the crushed silica is 9 m ² / g or more and 15 m ² / g or less, the content of the crushed silica is It is preferably 10 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the resin component. When the specific surface area of crushed silica increases, the melt viscosity of the resin composition during molding tends to increase. Therefore, in order to ensure the fluidity of the resin composition, it is preferable to suppress the content of crushed silica.

Since the molybdenum compound particles (d) are the same as those in Embodiment 1, the description thereof is omitted.

The resin composition may further contain a catalyst. Thereby, the curing reaction (crosslinking reaction) between the preliminary reaction product (a) and the cyanate ester compound (b) can be promoted. That is, the catalyst acts as a curing accelerator. Therefore, the high glass transition temperature, heat resistance, and adhesion of the cured product can be ensured.

As the catalyst, for example, what is generally called a metal soap can be used. For example, the metal salt of an organic acid is mentioned. Examples of the organic acid include octylic acid, naphthenic acid, stearic acid, lauric acid, ricinoleic acid, and acetyl acetate. Examples of the metal include zinc, copper, cobalt, lithium, magnesium, calcium, and barium. Among these, copper naphthenate is preferable because the activity of the cyanate ester trimerization reaction is low, and the pot life of the varnish or prepreg is relatively good while maintaining the heat resistance of the cured product. A catalyst may be used independently or may be used in combination of 2 or more type.

The compounding amount of the catalyst is preferably 0.001 part by mass or more and 1 part by mass or less with respect to 100 parts by mass of the total amount of the preliminary reaction product (a) and the cyanate ester compound (b). If the blending amount of the catalyst is within this range, the curing acceleration effect can be enhanced, the high heat resistance and glass transition temperature of the cured product can be secured, and a prepreg having no problem in moldability can be easily produced.

In addition to the hydrophobic silica particles (c) and the molybdenum compound particles (d), the inorganic filler may contain other fillers different from these. That is, by adding other fillers, in addition to the effect of lowering the coefficient of thermal expansion due to the hydrophobic silica particles (c), the coefficient of thermal expansion can be further reduced. Moreover, the characteristics which cannot fully be acquired only by hydrophobic silica particles (c), such as a flame retardance and heat conductivity, can be provided to hardened | cured material. Other fillers can be appropriately selected from known fillers according to the purpose and are not limited, but those having relatively low hardness that are difficult to reduce drill workability are preferable. Specific examples include aluminum hydroxide, magnesium hydroxide, aluminum silicate, magnesium silicate, talc, clay, mica and the like.

The resin composition may further contain, for example, additives such as a heat stabilizer, an antistatic agent, an ultraviolet absorber, a dye, a pigment, and a lubricant as long as the effects of the present invention are not impaired. .

The resin composition can be prepared and used as a varnish by mixing predetermined amounts of the various components described above in a solvent. The solvent is not particularly limited as long as it can dissolve the resin components such as the preliminary reaction product (a), the cyanate ester compound (b), and the epoxy compound (e) and does not inhibit the curing reaction. Examples thereof include organic solvents such as toluene, cyclohexanone, methyl ethyl ketone, and propylene glycol monomethyl ether acetate.

When preparing the varnish of the resin composition, in order to promote the dissolution / dispersion of the solid component, the resin component may be heated in a temperature range that does not cause a curing reaction, if necessary. Furthermore, when an inorganic filler or a halogen-based flame retardant is added as necessary, the varnish may be agitated using a ball mill, a bead mill, a planetary mixer, a roll mill, or the like until a good dispersion state is obtained.

In addition, it can replace with the resin composition in Embodiment 1, and can also form a prepreg, a metal-clad laminated board, and a printed wiring board also using the resin composition by this Embodiment. Since the method and the like are the same as those in the first embodiment, description thereof is omitted.

Hereinafter, the effects of the present embodiment will be further described with specific examples.

[1] Manufacturing procedure of laminate for evaluation (1) Resin composition <Preliminary reaction product>
In order to prepare the preliminary reaction product (a), the following materials are used.

“SA90” (number average molecular weight: 1500, hydroxyl group: 1.9) manufactured by SABIC Innovative Plastics is used as polyphenylene ether (PPE).

DCPD type epoxy resin is used as the epoxy compound. Specifically, “HP7200” (2.3 average functional groups in one molecule) manufactured by DIC Corporation is used.

Imidazole is used as the catalyst. Specifically, “2E4MZ” (2-ethyl-4-imidazole) manufactured by Shikoku Chemicals Co., Ltd. is used.

Each component was weighed so as to have a blending ratio shown in (Table 5), added to toluene, and then stirred at 100 ° C. for 6 hours. That is, the preliminary reaction product (a) is prepared by reacting (prereacting) polyphenylene ether and an epoxy resin in advance. The amount of toluene as the solvent to be added is adjusted so that the solid content concentration of the preliminary reaction product (a) is 60%.

<Cyanate ester compound>
In Samples AA to AF, AH, BA to BI, BP, and BQ, the following materials are used as a resin component together with the preliminary reaction product (a) in order to prepare a resin composition. That is, 2,2-bis (4-cyanatephenyl) propane is used as the cyanate ester compound (b). Specifically, it is “BADCy” manufactured by Lonza Japan.

Samples AG, BJ, and BK use the following materials together with the preliminary reaction product (a) as a resin component in order to prepare a resin composition. 2,2-bis (4-cyanatephenyl) propane is used as the cyanate ester compound (b), and a DCPD type epoxy resin is used as the epoxy compound (e). Specifically, “BADCy” manufactured by Lonza Japan Co., Ltd. and “EPICRON HP7200” manufactured by DIC Corporation (2.3 average functional groups in one molecule) are used.

<Catalyst>
Metal soap is used as a catalyst. Specifically, zinc octoate (Zn-OCTOATE) manufactured by DIC Corporation.

<Inorganic filler>
The silica particles are selected from seven types of crushed silica 1 (c), crushed silica 2 (c), crushed silica 3, spherical silica 1 (c), spherical silica 2 (c), spherical silica 3 and spherical silica 4. Used.

The crushed silica 1 (c) is a melt-crushed silica particle “Megasil 525RCS” manufactured by Sibelco Japan Co., Ltd., having an average particle size of 1.6 μm and a specific surface area of 2.1 m ² / g. The surface is treated with.

Crushed silica 2 (c) is crushed silica particles that have been subjected to a treatment (moisture absorption treatment) in which crushed silica 1 is left in an environment of 35 ° C. and 90% for 7 days (168 hours).

The crushed silica 3 is a fused crushed silica particle “Megasil 525” manufactured by Sibelco Japan Co., Ltd., the average particle diameter is 1.6 μm, and the specific surface area is 2.2 m ² / g. No surface treatment is applied.

The crushed silica 4 is crushed silica particles obtained by subjecting the crushed silica 3 to the above moisture absorption treatment.

The spherical silica 1 (c) is spherical silica particles “SC2500-SEJ” manufactured by Admatechs Co., Ltd., having an average particle diameter of 0.8 μm, a specific gravity of 2.2 g / cm ³ , and a specific surface area of 7 m ² / g and surface-treated with epoxysilane.

The spherical silica 2 (c) is crushed silica particles obtained by subjecting the spherical silica 1 to the above moisture absorption treatment.

The spherical silica 3 is spherical silica particles “SO-25R” manufactured by Admatechs Co., Ltd., having an average particle size of 0.6 μm and a specific surface area of 6 m ² / g. No surface treatment is applied.

The spherical silica 4 is crushed silica particles obtained by subjecting the spherical silica 3 to the above moisture absorption treatment.

As the molybdenum compound particles (d), calcium zinc molybdate “KEMGARD 911A” manufactured by Sherwin Williams is used. The amount of molybdic acid is 10% by mass, the specific gravity is 3.0 g / cm ³ , and the average particle size is 2.7 μm. Alternatively, the zinc molybdate-treated talc “KEMGARD911C” manufactured by Sherwin Williams used in the first embodiment is used.

The pre-reacted PPE (a) solution is heated to 30 to 35 ° C. so that the blending ratio shown in (Table 8) or (Table 9) is obtained, and the cyanate ester compound (b) and the catalyst are added thereto. is doing. In samples AG, BJ, and BK, a DCPD type epoxy resin is also added at this time. Thereafter, the mixture is completely dissolved by stirring for 30 minutes, and further, silica particles and molybdenum compound particles are added and dispersed by a bead mill to prepare a varnish of the resin composition.

Samples BL to BO use the same materials as Sample AA except that the following materials were used as the resin component and catalyst for preparing the resin composition.

<Resin component>
PPE: “SA90” (number average molecular weight 1500, hydroxyl group: 1.9) manufactured by SABIC Innovative Plastics
(catalyst)
Imidazole: “2E4MZ” (2-ethyl-4-imidazole) manufactured by Shikoku Kasei Kogyo Co., Ltd.
Metal soap: Zinc octoate (Zn-OCTOATE) manufactured by DIC Corporation
Each component was added to toluene so that the blending ratio shown in Table 8 was obtained, and then stirred at 30 to 35 ° C. for 60 minutes. Furthermore, the varnish of the resin composition is prepared by adding silica particles and molybdenum compound particles and dispersing them with a bead mill.

In samples AI, AJ, BR, and BS, the same material as that of sample AG is used in order to prepare a varnish of the resin composition. The pre-reacted PPE (a) solution was heated to 30 to 35 ° C. so that the blending ratios shown in (Table 6) and (Table 10) were obtained, and then the cyanate ester compound (b), DCPD type epoxy Resin, PPE and metal soap are added. Thereafter, the mixture is completely dissolved by stirring for 30 minutes, and further, silica particles and molybdenum compound particles are added and dispersed by a bead mill to prepare a varnish of the resin composition. Note that, unlike the samples BA, BD, and BP, the sample BR does not use new silica particles.

In sample BT, each component shown in (Table 7) was added to toluene so as to have the blending ratio shown in (Table 7) and (Table 10), and then stirred at 30 to 35 ° C. for 60 minutes. Silica particles and molybdenum compound particles are further added to this resin component and dispersed by a bead mill to prepare a varnish of the resin composition.

(2) Prepreg Using the same base material as in the first embodiment, a prepreg is manufactured in the same manner as in the first embodiment. The resin content (resin amount) of the prepreg is 57% by mass.

(3) Laminate A laminate for evaluation is manufactured using the prepreg in the same manner as in the first embodiment.

[2] Evaluation of Laminated Plate and its Results (1) Glass Transition Temperature The glass transition temperature of the laminated plate for evaluation was measured by DSC measurement method based on IPC-TM-650-24.25. The measurement is performed at 20 ° C./min.

(2) Dielectric loss tangent The dielectric loss tangent at 1 GHz of the evaluation laminate is measured by a method based on IPC-TM-650-2.5.5.9. Specifically, the dielectric loss tangent of the laminate for evaluation at 1 GHz is measured using an impedance analyzer (RF impedance analyzer HP4291B manufactured by Agilent Technologies).

(3) Drill wear rate The drill wear rate is evaluated in the same manner as in the first embodiment. Detailed description is omitted.

(4) Varnish gel time The varnish gel time is a value obtained by measuring the time required for 2.5 ml of the varnish of the obtained resin composition to gel on a cure plate at 200 ° C.

(5) Adsorbed moisture amount of silica particles, moisture amount brought into the resin composition The adsorbed moisture amount of silica particles and the moisture amount brought into the resin composition were determined as described above using the Karl Fischer method. ing.

(6) Thermal expansion coefficient (CTE)
The CTE is evaluated in the same manner as in the first embodiment. Detailed description is omitted. The CTE measurement results are shown for reference.

Samples AA to AJ use hydrophobic silica particles in which the silica particles are surface-treated. Therefore, the glass transition temperature is high and the dielectric loss tangent is low. Further, comparing the sample AA without moisture absorption with the sample AB with moisture absorption, and the sample AE without moisture absorption with the sample AF with moisture absorption, the glass transition temperature and the dielectric loss tangent are the same. That is, the glass transition temperature and dielectric properties are stable and excellent before and after the moisture absorption treatment. Furthermore, since the resin composition contains hydrophobic silica particles and molybdenum compound particles, the drill wear rate is low. That is, drilling workability and formability are good.

On the other hand, samples BA to BQ contain a pre-reacted product (a) of polyphenylene ether and an epoxy compound, a cyanate ester compound (b), hydrophobic silica particles (c) and molybdenum compound particles (d). It is not the obtained resin composition. Therefore, except for samples BA, BD and BP using new silica particles (silica particles in a dry state), the glass transition temperature and the dielectric properties are excellent, but good drillability and formability are not shown.

Comparing the sample BA without moisture absorption with the sample BB with moisture absorption, the sample BD without moisture absorption with the sample BE with moisture absorption, and the sample BP without moisture absorption with the sample BQ with moisture absorption, When silica particles that have been subjected to moisture absorption treatment are used in contrast to the case where silica particles that have not been applied are used, the glass transition temperature decreases, the dielectric loss tangent increases, and the varnish gel time is significantly shortened. That is, excellent glass transition temperature and dielectric properties are impaired after moisture absorption treatment. This tendency is the same even if the content of silica particles in the resin composition is reduced (sample BC).

Samples BF to BJ do not contain molybdenum compound particles. Therefore, the drill wear rate is high. That is, drill workability and formability are not good. Further, comparing the sample BF without moisture absorption and the sample BG after moisture absorption treatment, and the sample BH without moisture absorption treatment and the sample BI after moisture absorption treatment, the varnish gel time is equivalent to the samples AA to AJ. From this result and the results of samples BD and BE, it is presumed that the molybdenum compound particles promote the reduction of the varnish gel time.

In the samples BL and BM, the preliminary reaction PPE (a) is not used, so the glass transition temperature is low. When samples BL and BM are compared, the varnish gel time is the same regardless of whether or not moisture absorption treatment is performed, and is longer than samples AA to AJ.

Samples BN and BO have a low glass transition temperature and a high dielectric loss tangent because the resin component does not contain polyphenylene ether. When samples BN and BO are compared, the varnish gel time is the same regardless of the presence or absence of moisture absorption treatment, and is longer than samples AA to AJ. In contrast to this result and the results of samples BL and BM, the resin composition containing the pre-reacted product (a) of polyphenylene ether and epoxy compound, cyanate ester compound (b) and molybdenum compound particles (d) absorbs moisture. In samples BB, BC, BE, BK, and BQ using the silica particles, the varnish gel time is abnormally short.

Samples AI and AJ use hydrophobic silica particles in which silica particles are surface-treated. Therefore, the glass transition temperature is high and the dielectric loss tangent is low. When samples AI and AJ are compared, the glass transition temperature and the dielectric loss tangent are the same regardless of whether or not moisture absorption treatment is performed. That is, the glass transition temperature and dielectric properties are stable and excellent.

On the other hand, samples BR to BT were obtained by blending a prereacted product (a) of polyphenylene ether and an epoxy compound, a cyanate ester compound (b), hydrophobic silica particles (c) and den compound particles (d). It is not a resin composition obtained. Therefore, excellent glass transition temperature and dielectric properties cannot be realized.

In the sample BR, unlike the samples BA, BD, and BP, new silica particles are not used. That is, since silica particles having a high amount of adsorbed moisture are used, the varnish gel time is short.

Compared to sample BR using silica particles not subjected to moisture absorption treatment, sample BS using silica particles subjected to moisture absorption treatment has a lower glass transition temperature, increased dielectric loss tangent, and greatly increased varnish gel time. It has become shorter. That is, it can be seen that the glass transition temperature and dielectric properties are impaired after moisture absorption treatment.

In sample BT, since the preliminary reaction product (a) is not used, the glass transition temperature is low.

The cured product of the resin composition for wiring boards according to the present invention has a small coefficient of thermal expansion, good drillability, and good glass transition temperature and dielectric properties when applied to a printed wiring board. Since such a printed wiring board can be provided relatively inexpensively, the resin composition for wiring boards according to the present invention is useful.

2A Resin composition 4A Base material 10 Prepreg 12 Insulating layer 14 Metal foil 16 Conductive pattern 20 Metal-clad laminate 30 Printed wiring board

Claims (20)

1. A resin component containing a thermosetting resin;
   Crushed silica having a specific surface area in the range of 0.1 m ² / g or more and 15 m ² / g or less;
   Containing molybdenum compound particles having a molybdenum compound at least in a surface layer portion, and an inorganic filler,
   The content of the crushed silica is in the range of 10 parts by mass or more and 150 parts by mass or less with respect to 100 parts by mass of the resin component.
   Resin composition for printed wiring boards.
2. The molybdenum compound is at least one selected from the group consisting of zinc molybdate, calcium molybdate and magnesium molybdate,
   The resin composition for printed wiring boards according to claim 1.
3. The content of the molybdenum compound particles is in the range of 0.1% by volume or more and 10% by volume or less with respect to 100% by volume of the total amount of the inorganic filler.
   The resin composition for printed wiring boards according to claim 1.
4. The molybdenum compound content is in the range of 0.05 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the resin component.
   The resin composition for printed wiring boards according to claim 1.
5. The inorganic filler further includes spherical silica,
   The resin composition for printed wiring boards according to claim 1.
6. The content of the inorganic filler is in the range of 15 parts by mass or more and 400 parts by mass or less with respect to 100 parts by mass of the resin component.
   The resin composition for printed wiring boards according to claim 1.
7. The resin component is
   A preliminary reaction product obtained by reacting a polyphenylene ether and an epoxy compound having an epoxy group;
   A cyanate ester compound,
   The surface of the crushed silica is subjected to a hydrophobic treatment,
   The resin composition for printed wiring boards according to claim 1.
8. The resin composition for a printed wiring board according to claim 7, wherein the molybdenum compound is one or more selected from the group consisting of zinc molybdate, calcium molybdate, and magnesium molybdate.
9. The resin composition for a printed wiring board according to claim 7, wherein a content of the molybdenum compound particles is 0.1 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the resin component.
10. The content of the hydrophobic silica particles is 10 parts by mass or more and 200 parts by mass or less with respect to 100 parts by mass of the resin component.
    The resin composition for printed wiring boards according to claim 7.
11. A substrate;
    The resin composition for a printed wiring board according to claim 1, wherein the substrate is impregnated and semi-cured.
    Prepreg.
12. An insulating layer that is a cured product of the prepreg according to claim 11;
    A metal foil laminated on the insulating layer,
    Metal-clad laminate.
13. An insulating layer that is a cured product of the prepreg according to claim 11;
    A conductor pattern formed on the insulating layer,
    Printed wiring board.
14. Including a resin component and an inorganic filler;
    The resin component is
    A preliminary reaction product obtained by reacting a polyphenylene ether and an epoxy compound having an epoxy group;
    A cyanate ester compound,
    The inorganic filler is
    Surface-treated hydrophobic silica particles,
    Including molybdenum compound particles having a molybdenum compound in at least a surface layer portion,
    Resin composition for printed wiring boards.
15. The resin composition for a printed wiring board according to claim 14, wherein the molybdenum compound is one or more selected from the group consisting of zinc molybdate, calcium molybdate, and magnesium molybdate.
16. The resin composition for a printed wiring board according to claim 14, wherein a content of the molybdenum compound particles is 0.1 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the resin component.
17. The content of the hydrophobic silica particles is 10 parts by mass or more and 200 parts by mass or less with respect to 100 parts by mass of the resin component.
    The resin composition for printed wiring boards according to claim 14.
18. A substrate;
    A resin composition for a printed wiring board according to claim 14, wherein the substrate is impregnated and semi-cured.
    Prepreg.
19. An insulating layer that is a cured product of the prepreg according to claim 18;
    A metal foil laminated on the insulating layer,
    Metal-clad laminate.
20. An insulating layer that is a cured product of the prepreg according to claim 18;
    A conductor pattern formed on the insulating layer,
    Printed wiring board.

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