JP5691443B2 - Prepreg, laminated board using the same, and printed wiring board - Google Patents

Description

  The present invention relates to a prepreg obtained by applying a resin composition, which is suitable for a semiconductor package or a printed wiring board, to a substrate made of glass fiber and heating it, and a laminated board and a printed wiring board using the prepreg.

In recent years, electronic devices such as mobile phones and mobile devices have become increasingly smaller and lighter or thinner. As a result, electronic parts such as ICs and LSIs mounted on a printed wiring board inside the electronic device have been increased in density, and accordingly, the heat generation density inside the electronic device has increased.
When the heat generation density inside the electronic device increases, the temperature rise accompanying the heat generation inside the electronic device becomes remarkable, and the operation reliability of the electronic component decreases.
Therefore, in order to quickly release the heat generated from the electronic components and conductors to the outside, it is necessary to improve the heat dissipation of the printed wiring board.
Various proposals have been made as means for improving the heat dissipation of such a printed wiring board. For example, Patent Document 1 proposes a metal base laminate in which a metal plate is insulated and coated with a resin composition to which an inorganic filler is added. Patent Document 2 proposes a metal base laminate in which an insulating adhesive sheet made of an epoxy resin is attached to a metal plate. Further, Patent Document 3 proposes a laminate in which a layer of a prepreg obtained by impregnating an epoxy resin varnish into a sheet-like fiber base material in which aluminum nitride is impregnated and drying is heated and pressed. Patent Document 4 proposes a laminated board that maintains the thermal conductivity of the cured resin itself rather than the inorganic filler.

JP-A-6-216484 JP-A-8-167775 JP 2000-15746 A JP 2003-137971 A

The laminates of Patent Documents 1 to 3 have improved heat dissipation using a metal or inorganic ceramic with good thermal conductivity. However, in these methods, the workability is inferior compared to a laminate obtained by heat-pressing a prepreg layer obtained by impregnating a thermosetting resin varnish into a conventional sheet-like fiber substrate and drying, There is a problem that the insulating property is also lowered.
Moreover, the laminated board of patent document 4 is considered that the heat conductivity of a resin composition is high and is excellent in workability and insulation. However, even when a resin composition excellent in thermal conductivity is obtained, the prepreg or laminate obtained by impregnating the glass fiber fabric is often inferior to the thermal conductivity of the resin composition, In particular, when the thermal conductivity of the glass fiber fabric was lower than the thermal conductivity of the resin composition, the tendency of the thermal conductivity of the prepreg and the laminate to decrease was remarkable.

  Therefore, the present invention has been made in view of such circumstances, and an object of the present invention is to provide a prepreg that maintains excellent workability and insulation and is excellent in thermal conductivity. Another object of the present invention is to produce a laminated board and a printed wiring board using the prepreg excellent in thermal conductivity, and to provide a laminated board and a printed wiring board excellent in heat dissipation. is there.

  As a result of earnest research to solve the above-mentioned problems, the present invention is obtained by applying a resin composition having high thermal conductivity to a cloth made of glass fibers to which inorganic solid particles are adhered and heating the resin composition. The present inventors have found that the prepreg maintains excellent workability and insulation and is excellent in thermal conductivity, and has completed the present invention.

That is, the present invention
(1) (A) A resin composition having a thermal conductivity of 0.9 W / mK or more at 25 ° C. containing a thermosetting resin and an inorganic filler is obtained from (B) a glass fiber to which inorganic solid particles are attached. A prepreg obtained by coating and heating on a base material,
(2) The prepreg according to (1), wherein the thermosetting resin is an epoxy resin,
(3) The prepreg according to (1) or (2) above, wherein the content of the inorganic filler is 30 to 70% by volume of the entire resin composition,
(4) The above (1) to (3), wherein the inorganic filler is at least one selected from aluminum hydroxide, aluminum oxide, zinc oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, titanium oxide and boron nitride. ) The prepreg according to any one of
(5) The prepreg according to any one of (1) to (4), wherein the content of the inorganic solid particles is 0.1 to 2% by mass with respect to the glass fiber.
(6) The prepreg according to any one of (1) to (5), wherein the inorganic solid particles have an average particle size of 5 to 2000 nm.
(7) The prepreg according to any one of (1) to (6), wherein the inorganic solid particles are silicon oxide and / or titanium oxide.
(8) The prepreg according to any one of the above (1) to (7), wherein the thermal conductivity of the prepreg at 25 ° C. is 1.0 W / mK or more,
(9) A laminate formed by using the prepreg according to any one of (1) to (8) above,
(10) A printed wiring board formed by wiring the laminated board according to (9),
Is to provide.

  According to the present invention, it is possible to obtain a prepreg that maintains excellent workability and insulation and is excellent in thermal conductivity. Moreover, if a laminated board and a printed wiring board are produced using the said prepreg excellent in heat conductivity, the laminated board and printed wiring board excellent in heat dissipation will be obtained.

Hereinafter, embodiments of the present invention will be described in detail.
First, the resin composition used for this invention is demonstrated.
The resin composition used in the present invention is a resin composition having a thermal conductivity of 0.9 W / mK or more at 25 ° C. containing (A) a thermosetting resin and an inorganic filler. The material is included as an essential component.
Among these, examples of thermosetting resins include epoxy resins, phenol resins, unsaturated imide resins, amino resins, unsaturated polyester resins, allyl resins, dicyclopentadiene resins, silicone resins, triazine resins, melamine resins, and the like. It is done. Among these, an epoxy resin excellent in moldability and electrical insulation is preferable.
Examples of such epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, biphenyl type epoxy resins, alicyclic epoxy resins, phenol novolac type epoxy resins, and cresol novolak type epoxy resins. Bisphenol A novolak type epoxy resin, bisphenol F novolak type epoxy resin, dicyclopentadiene type epoxy resin, polyfunctional phenols, and polycyclic aromatic glycidyl ether compounds such as anthracene and naphthalene.

As the inorganic filler, it is preferable to use an inorganic filler having a high thermal conductivity of 3 W / mK or more at 25 ° C., for example, aluminum hydroxide (3 W / mK), aluminum oxide (20 to 30 W / mK), zinc oxide (54 W / mK), magnesium oxide (45-60 W / mK), magnesium carbonate (15 W / mK), magnesium hydroxide (8 W / mK), titanium oxide (8 W / mK), boron nitride (57 W) / mK). In addition, the numerical value in the parenthesis of the said inorganic filling material is a heat conductivity in about 25 degreeC.
Among these, aluminum hydroxide, aluminum oxide, zinc oxide, magnesium oxide, titanium oxide and boron nitride are preferable inorganic fillers having a thermal conductivity of 3 W / mK or more at 25 ° C.
Here, since the thermal conductivity depends on temperature, the thermal conductivity at 25 ° C., which is a temperature that is less constrained in measurement and easy to manage, is applied to the heat of inorganic fillers, resin compositions, prepregs, laminates, etc. Used as conductivity.

Further, the shape of the inorganic filler is preferably spherical particles with little decrease in fluidity when highly filled in the resin, and the inorganic filler has a cumulative 50% particle size of 0.1 to 10 μm, particularly 0. A thickness of 3 to 5 μm is preferable from the viewpoint of improving thermal conductivity.
Here, the cumulative 50% particle diameter is the particle diameter at a point corresponding to a volume of 50% when a cumulative frequency distribution curve based on the particle diameter is obtained with the total volume of the powder as 100%. It can be measured by a particle size distribution measuring apparatus using a method.

In the present invention, the content of the inorganic filler in the resin composition is preferably 30 to 70% by volume of the entire resin composition, more preferably 40 to 65% by volume, and 45 to 60% by volume. Is more preferable.
When the content of the inorganic filler is 30 to 70% by volume of the entire resin composition, the effect of increasing the thermal conductivity of the resin composition by the inorganic filler is large. As a result, the heat conduction of the resin composition at 25 ° C. This is because it is easy to set the rate to 0.9 W / mK or more, and the thermal expansion coefficient of the resin composition is reduced, so that a resin composition having appropriate fluidity and excellent moldability is obtained. Because it is.
Here, the volume% of the inorganic filler is a percentage of the volume occupied by the inorganic filler with respect to the total volume of the resin composition.

And if the heat conductivity in 25 degreeC of a resin composition is 0.9 W / mK or more, it combined with the base material which consists of the glass fiber to which the inorganic solid particle to mention later adheres, and the prepreg which has the outstanding heat dissipation, and A laminated board and a printed wiring board using this can be obtained. The thermal conductivity at 25 ° C. of this resin composition is preferably 1.0 W / mK or more, and more preferably 1.1 W / mK or more.
The thermal conductivity of the resin composition can be adjusted by adjusting the type and content of the inorganic filler to be contained.

In addition to the above components, a curing agent, a curing accelerator, a thermoplastic resin, an elastomer, a flame retardant, an ultraviolet absorber, an antioxidant, an adhesion improver, and the like can be added to the resin composition of the present invention.
Examples of curing agents include, for example, epoxy resins, polyfunctional phenol compounds such as phenol novolac and cresol novolac; amine compounds such as dicyandiamide, diaminodiphenylmethane, and diaminodiphenylsulfone; phthalic anhydride, pyromellitic anhydride, Acid anhydrides such as maleic anhydride and maleic anhydride copolymer; and the like can be used. Several kinds of these curing agents can be used in combination.

Examples of curing accelerators include, for example, epoxy resin curing accelerators such as imidazoles and derivatives thereof; organophosphorus compounds; secondary amines, tertiary amines, and quaternary ammonium salts; It is done.
Examples of such imidazoles and derivatives thereof include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 1-benzyl-2-methyl. Imidazole, 2-heptadecylimidazole, 4,5-diphenylimidazole, 2-methylimidazoline, 2-phenylimidazoline, 2-undecylimidazoline, 2-heptadecylimidazoline, 2-isopropylimidazole, 2,4-dimethylimidazole, 2 -Phenyl-4-methylimidazole, 2-ethylimidazoline, 2-isopropylimidazoline, 2,4-dimethylimidazoline, 2-phenyl-4-methylimidazoline and the like.
These imidazole compounds may be masked with a masking agent. Examples of the masking agent include acrylonitrile, phenylene diisocyanate, toluidine isocyaninate, naphthalene diisocyanate, methylene bisphenyl isocyanate, and melamine acrylate.

Examples of organophosphorus compounds include ethylenephosphine, propylphosphine, butylphosphine, phenylphosphine, trimethylphosphine, triethylphosphine, tributylphosphine, trioctylphosphine, triphenylphosphine, tricyclohexylphosphine, triphenylphosphine / triphenylborane complex, tetra Examples include phenylphosphonium tetraphenylborate.
Secondary amines include morpholine, piperidine, pyrrolidine, dimethylamine, diethylamine, dicyclohexylamine, N-alkylarylamine, piperazine, diallylamine, thiazoline, thiomorpholine and the like.
Tertiary amines include benzyldimethylamine, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (diaminomethyl) phenol, and the like.
Quaternary ammonium salts include tetrabutylammonium iodide, tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium fluoride, benzalkonium chloride, benzyldi (2-hydroxyethyl) ethylammonium chloride, decyldi (2- And hydroxyethyl) methylammonium bromide.
In addition, you may use 2 or more types together for the kind and compounding quantity of the said hardening accelerator.

Examples of thermoplastic resins include, for example, polyethylene, polypropylene, polystyrene, polyphenylene ether resin, phenoxy resin, polycarbonate resin, polyester resin, polyamide resin, polyamideimide resin, polyimide resin, xylene resin, polyphenylene sulfide resin, polyetherimide resin, Examples include polyether ether ketone resins and polyether imide resins.
Examples of elastomers include polybutadiene, acrylonitrile, epoxy-modified polybutadiene, maleic anhydride-modified polybutadiene, phenol-modified polybutadiene, carboxy-modified acrylonitrile, and the like.

Examples of flame retardants include, for example, halogen-containing flame retardants containing bromine and chlorine, triphenyl phosphate, tricresyl phosphate, trisdichloropropyl phosphate, phosphazenes, red phosphorus and other phosphorus flame retardants; antimony trioxide; etc. Inorganic flame retardants.
Other examples of UV absorbers include benzotriazole UV absorbers, examples of antioxidants include hindered phenols and styrenated phenols, and examples of adhesion improvers include urea compounds such as urea silane. And silane coupling agents.
Of these, specific examples of silane coupling agents include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyl (methyl) dimethoxysilane, and 2- (2,3-epoxycyclohexyl) ethyltrimethoxy. Epoxy group-containing silane such as silane; 3-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyl (methyl) Amino group-containing silanes such as dimethoxysilane; cationic silanes such as 3- (trimethoxylyl) propyltetramethylammonium chloride; vinyl group-containing silanes such as vinyltriethoxysilane; 3-methacryloxypropyltrimethoxysilane Acrylic group-containing silanes such as; and 3- Mercapto group-containing silane such as Le mercaptopropyl trimethoxysilane.

Since the resin composition of the present invention is used in a prepreg, it is preferable that each component is blended in a state where it is dissolved or dispersed in an organic solvent, and finally provided in a varnish state.
Examples of the organic solvent used here include alcohols such as methanol, ethanol, propanol and butanol; glycol ethers such as methyl cellosolve, butyl cellosolve and propylene glycol monomethyl ether; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; Esters such as butyl acetate and propylene glycol monomethyl ether acetate; Ethers such as tetrahydrofuran; Aromatic hydrocarbons such as toluene and xylene; Nitrogen-containing solvents such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone; Dimethyl sulfoxide and the like Or a mixture of two or more of them.

Among these, methyl isobutyl ketone, methyl ethyl ketone, propylene glycol monomethyl ether and methyl cellosolve are preferable from the viewpoint of solubility, and methyl isobutyl ketone and propylene glycol monomethyl ether are more preferable from the viewpoint of low toxicity.
Further, the order of blending is preferably such that the inorganic filler is dispersed in an organic solvent in advance and then mixed with components other than the inorganic filler such as a thermosetting resin.
When dispersing the inorganic filler in the organic solvent, a disperser such as a bead mill, a homogenizer, or a jet mill can be used to improve dispersibility. In addition, it is also preferable to pre-treat the inorganic filler with a surface treatment agent such as a silane or titanate coupling agent or a silicone oligomer, or an integral blend treatment.

  It is preferable that the resin composition in the varnish finally obtained is 40 to 90 mass% of the whole varnish, and it is more preferable that it is 50 to 80 mass%. If it is within this range, it is easy to produce a prepreg having an appropriate amount of the resin composition attached, and the viscosity of the varnish becomes an appropriate viscosity and is excellent in coatability.

Next, the base material used for this invention is demonstrated.
The base material used for this invention is a base material which consists of a glass fiber to which (B) inorganic solid particle has adhered, and it is necessary for the inorganic solid particle to adhere to glass fiber.
Examples of the glass fiber used in the present invention include glass fibers such as E glass, D glass, S glass, and Q glass.
The glass fiber has, for example, a woven fabric, a non-woven fabric, a robink, a chopped strand mat, a surfacing mat, and the like, and the material and shape are selected depending on the intended use and performance of the laminate, and if necessary. A single material or a combination of two or more materials and shapes can be used. Among these, woven fabric or nonwoven fabric is particularly preferable.

As the substrate of the present invention, a glass fiber to which inorganic solid particles are adhered, that is, a glass fiber converging agent containing inorganic solid particles is used. This base material is important in that the inorganic solid particles are in contact with the glass fiber, and the inorganic solid particles are in contact with the glass fiber, so that the heat conduction between the resin composition and the base material is smooth, and the entire prepreg The thermal conductivity of can be improved.
The content of the inorganic solid particles is preferably 0.1 to 2% by mass and more preferably 0.2 to 1% by mass with respect to the glass fiber mass.
The inorganic solid particles preferably contain at least one kind of silicon oxide such as colloidal silica and titanium oxide. The average particle size of the inorganic solid particles is preferably 5 to 2000 nm, but in particular considering the ease of application of the resin composition, the thermal conductivity of the prepreg, etc., it is 10 to 1000 nm. Is preferred.
The thermal conductivity at 25 ° C. of the base material made of glass fiber to which such inorganic solid particles are attached is 1.0 to 1.1 W / mK.

As a method for attaching the inorganic solid particles to the glass fiber, for example, methods described in JP-A-9-208268, JP-A-6-248572, and the like can be used.
The substrate made of glass fibers to which the inorganic solid particles of the present invention are attached is further heat-treated, moisture-resistant, and is surface-treated with a silane coupling agent or the like or mechanically subjected to fiber opening treatment. From the viewpoint of workability and the like.
As the thickness of the substrate made of the glass fiber to which the inorganic solid particles of the present invention are attached, for example, a thickness of 0.01 to 0.2 mm can be adopted.

Next, the prepreg obtained by applying the resin composition (A) to the substrate (B) and heating it will be described.
The prepreg of the present invention is obtained by applying the resin composition of the above (A) to a substrate made of glass fiber to which the inorganic solid particles of the above (B) are adhered by a method such as impregnation, spraying, extrusion, etc. It can be manufactured by being semi-cured by heating. In particular, a method of impregnating a substrate with the resin composition varnish and heating and semi-curing is preferable because it is excellent in productivity.
The heating temperature and time vary depending on the type of resin, the type of organic solvent contained in the varnish, and the type and amount of curing accelerator.

Moreover, in this invention, said prepreg can be laminated | stacked and used as a laminated board. The method for producing the laminated plate is not particularly limited. For example, the prepreg of the present invention is stacked 1 to 20 sheets, and a metal foil such as copper or aluminum is arranged on one or both sides thereof. Then, using a continuous molding machine, an autoclave molding machine, etc., a metal foil-clad laminate is manufactured by laminating at a temperature of 100 to 250 ° C., a pressure of 0.2 to 10 MPa, and a heating time of 0.1 to 5 hours. be able to. The metal foil is not particularly limited as long as it is used for electronic parts. Moreover, the prepreg of the present invention and the inner layer wiring board can be laminated and molded to produce a multilayer board.
Furthermore, it is possible to form a printed wiring board by forming wiring on this laminated board by an ordinary method.

Next, a method for evaluating thermal conductivity will be described.
The thermal conductivity of the resin composition, prepreg and laminate can be determined by the product of thermal diffusivity, constant pressure specific heat capacity and density.
The thermal diffusivity and the constant pressure specific heat capacity can be measured by a flash method. The flash method includes a laser flash method and a xenon flash method, and any of these methods can be used. The constant pressure specific heat capacity can be determined by differential scanning calorimetry (DSC). The density can be measured by the Archimedes method.
In addition, since thermal conductivity has temperature dependence, all measurements were performed at the same temperature of 25 ° C.

Examples of the present invention will be described below, but the present invention is not limited to these examples.
Examples 1-4, Comparative Examples 1-5
Among the blends of the resin compositions shown in Tables 1 and 2, first, the inorganic filler is 1.0% by mass of the silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: After dry treatment with KBM403), the mixture was added to 1 kg of propylene glycol monomethyl ether methyl with stirring and dispersed to obtain a dispersion of inorganic filler.
Next, the thermosetting resin and the curing agent are added to 1 kg of a mixed solvent of methyl ethyl ketone and propylene glycol monomethyl ether (mixing weight ratio: 2 to 1), and then stirred until the thermosetting resin and the curing agent are uniform. As a result, a varnish of a thermosetting resin was obtained.

Then, the dispersion liquid of the inorganic filler was added to the thermosetting resin varnish while stirring, and after the dispersion liquid and other components were sufficiently mixed, a curing accelerator was further added and stirred until the whole became uniform. . Finally, propylene glycol monomethyl ether was added to adjust the concentration so that the content of the resin composition was 70% by mass to obtain a varnish of the resin composition.
Moreover, the resin composition powder was obtained from a film obtained by coating the varnish of the resin composition on a glass plate and heating and drying at 160 ° C. for 5 minutes. The resin composition powder was molded at a temperature of 185 ° C. and a pressure of 3.5 MPa for 1.5 hours to obtain a resin plate. The resin plate was cut to a size of 10 mm square to produce a resin plate for thermal conductivity evaluation. The thermal conductivity at 25 ° C. of the resin plate was determined by the thermal conductivity evaluation method shown below, and it was judged whether it exceeded 0.9 W / mK.

Next, an E glass cloth treated with colloidal silica (IPC spec 2116, thickness 0.1 mm, content of colloidal silica: 0.1 to 2% by weight with respect to E glass cloth) , 25 ° C. thermal conductivity: 1.0 to 1.1 W / mK) and dried by heating at 160 ° C. for 5 minutes to obtain a prepreg having a resin composition content of 60% by volume. As a comparative material for glass cloth, an untreated E glass cloth (IPC spec 2116, thickness 0.1 mm, thermal conductivity 1.03 W / mK) and E glass cloth with improved air permeability and improved resin impregnation properties ( A prepreg was obtained in the same manner using an IPC spec 1080 (thickness 0.05 mm).
Next, 4 sheets of this prepreg were stacked, 18 μm electrolytic copper foils were placed one above the other, and laminate molding was performed at a temperature of 185 ° C. and a pressure of 3.5 MPa for 1.5 hours to obtain a copper clad laminate. After removing the copper foil of the copper-clad laminate with an etching solution, it was cut into a 10 mm square size to produce a thermal conductivity evaluation substrate.

(Measurement of thermal conductivity)
The thermal conductivity was obtained from the product of thermal diffusivity, constant pressure specific heat capacity and density.
The thermal diffusivity was measured using a xenon flash method (Nano Flash LEA447, manufactured by NETZSCH), the constant pressure specific heat capacity was measured using DSC (PE Pyris Series Pyris 1, manufactured by PerkinElmer), and the density was measured by an electronic hydrometer ( SD-200L, manufactured by Alpha Mirage).
The thermal diffusivity and density were measured at 25 ° C., and the specific heat capacity at 25 ° C. was also derived by measurement. The results are shown in Tables 1 and 2.

The numerical values in Tables 1 and 2 are shown as parts by mass when the amount of the thermosetting resin is 100 parts by mass. However, the total content of the inorganic filler indicated by * 1 in Tables 1 and 2 represents the content of the inorganic filler with respect to the entire resin composition in volume%.
Moreover, the following were used for each component in Tables 1 and 2, respectively.
Thermosetting resin: phenol novolac type epoxy resin (Dainippon Ink Chemical Co., Ltd., trade name: Epicron N-770)
Curing agent: Cresol novolak type phenolic resin (Dainippon Ink Chemical Co., Ltd., trade name: KA-1165)
Curing accelerator: 2-ethyl-4-methylimidazole (manufactured by Shikoku Kasei Co., Ltd., trade name: 2E4MZ)
・ Inorganic filler:
MgO: Magnesium hydroxide (Kyowa Chemical Co., Ltd., trade name: Pyroskima 5301K)
Al (OH) ₃ : Aluminum hydroxide (manufactured by Sumitomo Chemical Co., Ltd., trade name: CL-310)
Al ₂ O ₃ : Aluminum oxide (manufactured by Sumitomo Chemical Co., Ltd., trade name: AA-1.5)
SiO ₂ : Spherical amorphous silica (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name: SFP-30M)

As is clear from Tables 1 and 2, Examples 1 to 4 of the present invention and Comparative Examples 1 and 2 indicate the thermal conductivity of the resin composition at 25 ° C. (hereinafter simply referred to as “thermal conductivity”). The thermal conductivity at 25 ° C. is 0.9 W / mK or higher, but only Examples 1 to 4 using glass cloth treated with colloidal silica have a thermal conductivity of 1.0 W / mK or higher. Can be obtained. Moreover, in Comparative Examples 3 and 4 in which the thermal conductivity of the resin composition is less than 0.9 W / mK, the thermal conductivity of the laminate was 0.54 W / mK or less, and the thermal conductivity was inferior.
This is thought to be due to the magnitude relationship between the thermal conductivity of the glass cloth and the thermal conductivity of the resin composition. The thermal conductivity of glass cloth (glass cloth not treated with colloidal silica and glass cloth treated with colloidal silica) is in the range of 0.9 to 1.1 W / mK, but the thermal conductivity of the resin composition is It was found that a prepreg (laminated plate) having excellent thermal conductivity was obtained only when the glass cloth was equal or higher (0.9 W / mK or more) and treated with colloidal silica.

Moreover, from Example 1 and Comparative Example 5, it was found that high thermal conductivity as in Examples 1 to 4 could not be obtained simply by adding silica to the resin composition as an inorganic filler.
Furthermore, the workability and insulation of these laminates were comparable to the conventional ones.
Therefore, according to the present invention, it can be seen that a prepreg having excellent workability and insulation and excellent thermal conductivity can be obtained, and a prepreg suitable for a semiconductor package or a printed wiring board, a laminated board, and a printed wiring. It has been found that a substrate can be obtained.

  According to the present invention, a prepreg that maintains excellent workability and insulation and is excellent in thermal conductivity can be obtained. Therefore, the prepreg, a laminated board using the prepreg, and a printed wiring board can be used as a semiconductor package or a printed circuit board. It is suitably used for manufacturing a wiring board.

Claims (8)

(A) A resin composition having a thermal conductivity of 0.9 W / mK or more at 25 ° C. containing a thermosetting resin and an inorganic filler, and (B) a substrate made of glass fiber to which inorganic solid particles are attached. It was applied to, a prepreg obtained by heating,
The inorganic solid particles are silicon oxide and / or titanium oxide;
The prepreg whose thermal conductivity in 25 degreeC of the said prepreg is 1.0 W / mK or more .   The prepreg according to claim 1, wherein the thermosetting resin is an epoxy resin.   The prepreg according to claim 1 or 2, wherein the content of the inorganic filler is 30 to 70% by volume of the entire resin composition.   The prepreg according to any one of 1 to 3, wherein the inorganic filler is at least one selected from aluminum hydroxide, aluminum oxide, zinc oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, titanium oxide, and boron nitride. .   The prepreg according to any one of claims 1 to 4, wherein the content of the inorganic solid particles is 0.1 to 2 mass% with respect to the glass fiber.   The prepreg according to any one of claims 1 to 5, wherein the inorganic solid particles have an average particle size of 5 to 2000 nm. The laminated board laminated | stacked and formed using the prepreg in any one of Claims 1-6 . A printed wiring board obtained by wiring the laminated board according to claim 7 .