JPH09111004A - Production of composite material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composite material having small thermal expansion coefficient, high insulation resistance and excellent soldering heat-resistance after moisture-absorption treatment by treating a reinforcing material containing inorganic particles with a specific surface-treating material before impregnating a varnish into the reinforcing material. SOLUTION: A reinforcing material composed of a strand of collected monofilaments (preferably glass cloth) is mixed with 1-30 pts.wt. (based on 100 pts.wt. of the reinforcing material) of inorganic particles having an average particle diameter of <=1,000nm (preferably colloidal silica), the obtained reinforcing material containing the inorganic particles is surface-treated with a surface- treating agent containing an aminosilane-type coupling agent and/or a methacrylsilane-type coupling agent, the treated reinforcing material is impregnated with a varnish containing polyphenylene oxide, triallyl isocyanurate and a styrene-butadiene copolymer, the impregnated product is dried and the obtained prepreg is formed to obtain the objective composite material. The amount of the surface-treating agent applied to the reinforcing material is preferably 0.05-1 pt.wt. based on 100 pts.wt. of the surface-treated reinforcing material containing the inorganic particles.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a composite material produced by molding a prepreg obtained by impregnating a reinforcing material with a varnish containing polyphenylene oxide, triallyl isocyanurate and a styrene-butadiene copolymer and then drying the prepreg. It relates to a manufacturing method.

[0002]

2. Description of the Related Art As a recent trend of materials used for electronic devices, there is an attempt to realize high speed and high density as well as miniaturization and weight reduction. Leadless chip carrier (LCC) is one of the means to achieve the purpose.
Surface mounting technology (SMT) of the. For example, when the LCC of alumina is directly mounted on the printed circuit board, if the thermal expansion coefficients of the alumina and the printed circuit board are different,
Cracks occur in the solder at the joint due to thermal history. Therefore, in the case of direct mounting, the thermal expansion coefficient of the printed circuit board should be the same as that of the LCC (7 ppm for alumina).
/ ° C) is desirable. further,
There have also been attempts to directly mount bare silicon chips in leadless fashion. For that purpose, the thermal expansion coefficient of the printed circuit board must be the same as that of silicon (3-4 ppm /
(° C) is desirable.

As a means for reducing the coefficient of thermal expansion of a printed circuit board, the inventors of the present invention have filed Japanese Patent Application No. 6-108.
No. 816 is a composite material in which a resin is reinforced by a reinforcing material composed of strands formed by bundling monofilaments, and the strands have an average particle diameter of 1000 nm.
A low thermal expansion composite material containing the following inorganic particles in a proportion of 1 part by weight or more based on 100 parts by weight of the reinforcing material is proposed. However, in this composite material, it was found that swelling may occur when a solder test is performed after moisture absorption treatment such as PCT treatment. One of the reasons for this is considered to be that the inclusion of the inorganic particles in the strands creates a gap in the strands where the resin is less likely to enter, resulting in pores (small cavities). Therefore, the present inventors have found that by improving the impregnation method and the molding method, it is possible to produce a composite material having no pores and excellent solder heat resistance after moisture absorption treatment, and Japanese Patent Application No. 7-151850 and Wishhei 7-1518
No. 69 proposes a new manufacturing method. But,
Further investigation, even if such an impregnation method or a molding method is improved, depending on the method of surface treatment of the reinforcing material containing inorganic particles, insulation resistance after moisture absorption treatment of the obtained composite material or after moisture absorption treatment It has become clear that there may be a problem in solder heat resistance.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a reinforcing material composed of strands formed by bundling monofilaments with an average particle diameter of 1000 nm. After including the following inorganic particles, polyphenylene oxide in the reinforcing material,
A method for producing a composite material, comprising impregnating a varnish containing triallyl isocyanurate and a styrene-butadiene copolymer, and then molding the resulting prepreg to obtain a composite material, which comprises insulation resistance after moisture absorption treatment and solder after moisture absorption treatment. It is to provide a method capable of obtaining a composite material having excellent heat resistance.

[0005]

According to a first aspect of the present invention, there is provided a method for producing a composite material, wherein a reinforcing material composed of strands formed by bundling monofilaments has an average particle diameter of 1000 nm.
1 to 100 parts by weight of the following inorganic particles
In a proportion of 30 parts by weight, the reinforcing material containing the inorganic particles was impregnated with a varnish containing polyphenylene oxide, triallyl isocyanurate and a styrene-butadiene copolymer, and dried to obtain a prepreg, and then the prepreg was molded. In the method for producing a composite material for producing a composite material, a reinforcing material containing inorganic particles before impregnating a varnish, using a surface treatment agent containing an aminosilane coupling agent and / or methacrylsilane coupling agent, It is characterized by being surface-treated.

According to a second aspect of the present invention, there is provided a method for producing a composite material according to the first aspect, wherein the surface treatment of the reinforcing material containing inorganic particles is performed such that the amount of the surface treatment agent adhered to the surface is It is characterized in that it is applied in an amount of 0.05 to 1.0 part by weight with respect to 100 parts by weight of the reinforcing material containing the inorganic particles after the treatment.

According to a third aspect of the present invention, there is provided a method for producing a composite material according to the first or second aspect, wherein the reinforcing material composed of strands formed by bundling monofilaments is a glass cloth and has an average particle diameter. The material of the inorganic particles of 1000 nm or less is silica.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION As the reinforcing material in the present invention,
The thing which consists of the strand which a monofilament bundled is used. The monofilament preferably has low thermal expansion, but is not particularly limited. The material of the monofilament is not particularly limited, but is preferably one or more kinds of glass (for example, E glass, D glass, Q glass, S glass, T glass, etc.) and aramid resin. Regarding the length of the strand, long fibers or short fibers may be used. From the viewpoint of low thermal expansion, the form of the reinforcing material is preferably such that the resin content is as small as possible. The reinforcing material in such a form is not particularly limited, but examples thereof include mats, sheets, cloths (for example, plain weave, satin weave, and the like), and fiber moldings such as composites thereof. . Of the above-mentioned reinforcing materials, glass cloth is particularly preferable. The reason is that since the cross shape is dense, the resin content can be reduced and the filament continuity is high, which is effective in reducing the thermal expansion of the composite material. Further, glass is preferable because it is inexpensive and
This is because long fibers can be stably obtained.

The inorganic particles having an average particle size of 1000 nm or less contained in the reinforcing material are themselves materials having low thermal expansion. The coefficient of thermal expansion is not particularly limited, but is 10
It is preferably ppm / ° C. or less. If the coefficient of thermal expansion of the inorganic particles is larger than 10 ppm / ° C, the coefficient of thermal expansion of the composite material will be alumina (7 ppm / ° C) or silicon (3 to 4).
(ppm / ° C.) is too large. The amount of the inorganic particles having an average particle size of 1000 nm or less is 1 to 3 parts by weight with respect to 100 parts by weight of the reinforcing material before the inorganic particles are contained.
It is important to be in the range of 0 parts by weight. This amount is 1
If the amount is less than 10 parts by weight, a composite material having a small coefficient of thermal expansion cannot be obtained, and if the amount of the inorganic particles exceeds 30 parts by weight with respect to 100 parts by weight of the reinforcing material before the inorganic particles are contained, the composite material is obtained. This is because there arises a problem that the moisture resistance of the material is likely to deteriorate.

The reason for using the inorganic particles having an average particle size of 1000 nm or less is as follows. Since the monofilaments that compose the strands are usually several μm thick, the gap between the monofilaments is on the order of microns. Therefore, in order to easily include the inorganic particles even inside the strands, the average particle size is 1 μm. (= 1000
This is because it is preferably less than or equal to (nm). further,
Inorganic particles having a small average particle diameter are preferable because they are easily monodispersed in a treatment liquid containing water or the like as a medium.

The average particle size of the inorganic particles is 1
More preferred are ~ 100 nm colloidal particles. This is because such an inorganic particle has a smaller particle size, so that it can enter the gap between the narrower strands. However, the smaller the average particle size of the colloidal particles, the better. If it is less than 1 nm, the specific surface area of the colloidal particles becomes very large, which makes it difficult to control the interface with the resin. The lower limit of the average particle size is 1
nm.

The inorganic particles having an average particle diameter of 1000 nm or less are not particularly limited, but submicron-order commercially available particles such as fused silica and fine particle alumina are preferable. The colloidal particles having a smaller particle size are not particularly limited, but sol such as silica sol, alumina sol, titania sol, ultrafine particle silica, and ultrafine particle titania are preferable. Among these colloidal particles, silica is particularly preferable. The reason is that silica is
This is because the coefficient of thermal expansion is low (0.55 ppm / ° C.) among particles that are easily available. In addition to the particles described above, submicron particles and colloidal particles can be obtained by mechanically crushing with a ball mill or the like by using balls having a small diameter. Here, since the material to be crushed is desired to be a low thermal expansion material, silica glass, E glass, glass such as T glass, crystallized glass in which β-spodumene is precipitated, boron nitride, silicon nitride, mullite. , Aluminum nitride, cordierite, aluminum titanate (Al ₂ O ₃ TiO ₂ ), β-eucryptite and the like are preferable.

The strands may contain only inorganic particles having an average particle diameter of 1000 nm or less as a low thermal expansion material. In addition to the inorganic particles, a reaction product of a metal alkoxide also serves as a low thermal expansion material. It is also possible to include it. The metal alkoxide is completely soluble in a solvent such as alcohol. Therefore, the metal alkoxide has the property of being able to easily enter the inside of the strand by impregnating the treatment liquid containing the metal alkoxide into the reinforcing material, similarly to the above-mentioned inorganic particles. Since the reaction product of the metal alkoxide generally forms an inorganic film which is a continuous phase, it is different from the inorganic particles having an average particle size of 1000 nm or less in the present invention. The metal alkoxide is not particularly limited, but silicon alkoxide, titanium alkoxide, aluminum alkoxide, magnesium alkoxide, lithium alkoxide and the like are preferable. The reason is that the reaction product of the metal alkoxide can be easily obtained by using these raw materials. Among these metal alkoxides, silicon alkoxide is more preferable. This is because silicon alkoxide is inexpensive and has high stability among the above metal alkoxides, and the thermal expansion coefficient of silica, which is a reaction product thereof, is low (0.55 ppm / ° C.).

The method of incorporating the inorganic particles having an average particle diameter of 1000 nm or less in the reinforcing material in the present invention is not particularly limited, but for example, the inorganic particles are dispersed in a medium such as water or alcohol to prepare a treatment liquid. Is adjusted, the reinforcing liquid is impregnated with the treatment liquid, and then dried.

In the present invention, polyphenylene oxide,
Surface treatment of a reinforcing material containing inorganic particles with a surface treating agent containing an aminosilane coupling agent and / or a methacrylsilane coupling agent before impregnating a varnish containing triallyl isocyanurate and a styrene butadiene copolymer. To do. Here, the aminosilane-based coupling agent is a silane-based coupling agent having at least one amino group in the molecule, and there is no particular limitation on the number or type of side chains or the type of alkoxy group. Specific examples include those represented by the following formulas (a) to (d).

[0016]

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The methacrylsilane-based coupling agent is a silane-based coupling agent having at least one methacryl group in the molecule, and there is no particular limitation on the number or type of side chains or the type of alkoxy group. Specific examples include those represented by the following formula (e).

[0018]

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The method of surface treatment is not particularly limited, but a method in which a solution of a silane coupling agent dissolved in a medium such as water or alcohol is impregnated into a reinforcing material containing inorganic particles, and then heat treatment is carried out. Can be mentioned. Then, the surface treatment of the reinforcing material containing the inorganic particles is performed such that the amount of the surface treatment agent adhered to the reinforcing material is the reinforcing material 100 containing the inorganic particles after the surface treatment.
It is desirable that the amount is 0.05 to 1.0 part by weight with respect to parts by weight. This is because when the amount is less than 0.05 parts by weight, the effect of the surface treatment that makes the insulation resistance after the moisture absorption treatment and the solder heat resistance after the moisture absorption treatment excellent is not remarkable, and the adhesion exceeds 1.0 parts by weight. This is because the effect of the surface treatment does not increase even if it is carried out.

In the present invention, a varnish containing polyphenylene oxide, triallyl isocyanurate and a styrene-butadiene copolymer is used as a varnish for impregnating a reinforcing material containing inorganic particles. This polyphenylene oxide (hereinafter referred to as PPO) is represented by, for example, the following general formula (f), and has an action of reducing the dielectric loss tangent of the obtained composite material.

[0021]

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In the general formula (f), R represents hydrogen or a hydrocarbon group having 1 to 3 carbon atoms, and each R may be the same or different. Further, n is a positive number indicating the number of repetitions.

An example of PPO is poly (2,6-dimethyl-1,4-phenylene oxide),
A polymer having a molecular weight (M _W ) of 50,000 and M _W / M _n = 4.2 is preferably used.

The reason why triallyl isocyanurate is contained in the varnish in the present invention is that it has good compatibility with PPO and has a preferable action in terms of crosslinkability, heat resistance and dielectric properties. The reason why the styrene-butadiene copolymer is contained in the varnish is that it is a polymer having a cross-linking property and also has a preferable action in terms of cross-linking property and heat resistance. Further, the varnish containing PPO, triallyl isocyanurate and styrene-butadiene copolymer preferably contains an initiator such as peroxide together with these raw materials in order to obtain an appropriate curing rate (crosslinking rate).

In the present invention, the surface-treated reinforcing material is impregnated with varnish and dried to obtain a prepreg.
This prepreg is molded to produce a composite material, but the impregnation method, molding method, molding conditions, etc. are not particularly limited and may be appropriately determined according to the application. However, the molding is preferably carried out under reduced pressure from the viewpoint that the solder heat resistance after moisture absorption is excellent.

[0026]

EXAMPLES Examples of the present invention and comparative examples will be described below, but the present invention is not limited to the following examples.

(Example 1) E-glass plain weave cloth (manufactured by Asahi Schwebel, product number 216AS450, thickness 100 μ
m, fiber diameter 7 μm, driving density (number of strands / 2
5mm): Length 60 / 25mm, Width 55 / 25mm]
First, a colloidal silica aqueous solution (manufactured by Nissan Chemical Industries,
The product was impregnated with Snowtex OL (trade name), colloidal silica having an average particle diameter of 45 nm, and colloidal silica content of 20% by weight), and then pulled up at a speed of 3 cm / sec. Then 1
Heat treatment was performed at 50 ° C. for 5 minutes. By repeating this coating operation twice, a reinforcing material was obtained in which the adhered amount of colloidal silica was 15 parts by weight with respect to 100 parts by weight of the reinforcing material before containing colloidal silica.

Thereafter, the reinforcing material containing colloidal silica was added to a solution of N-phenyl-γ-aminopropyltrimethoxysilane (aminosilane coupling agent) manufactured by Shin-Etsu Chemical Co., Ltd., product number KBM573 at a concentration of 1% by weight. After immersion and passing through a squeezing roll, heat treatment at 110 ° C. for 5 minutes allows the amount of the surface treatment agent attached to the reinforcing material to be 100 parts by weight of the reinforcing material containing the inorganic particles after the surface treatment.
A reinforcement of 0.52 parts by weight was obtained.

Next, a varnish containing PPO, triallyl isocyanurate and styrene-butadiene copolymer was impregnated into the surface-treated reinforcing material obtained above, and two rolls having a roll interval of 0.2 mm were used. It passed through and was dried at 130 ° C. for 5 minutes to obtain a prepreg. The varnish had a molecular weight (M _W ) of 50,0 as PPO.
00, M _W / M _n = 4.2, poly (2,6-dimethyl-
1,4-phenylene oxide) and PPO: 5
0 parts by weight, triallyl isocyanurate: 40 parts by weight,
Styrene-butadiene copolymer: 10 parts by weight, dicumyl peroxide: 2 parts by weight, and trichloroethylene: an appropriate amount were mixed and prepared.

Ten sheets of the obtained prepreg were piled up, and 200
180 ° C., 30 kg / cm ² under reduced pressure of Torr
The substrate (composite material) was obtained by press molding for 90 minutes under the above molding conditions.

(Example 2) Concerning the surface treatment of the reinforcing material containing colloidal silica, the concentration of the product number KBE903 manufactured by Shin-Etsu Chemical Co., Ltd., in which the reinforcing material is γ-aminopropyltriethoxysilane (aminosilane coupling agent). After immersing in a 1 wt% aqueous solution and passing through a squeeze roll,
By heat treatment at 0 ° C. for 5 minutes, the amount of the surface treatment agent attached to the reinforcing material is such that the reinforcing material 1 containing inorganic particles after the surface treatment
A substrate (composite material) was obtained in the same manner as in Example 1 except that 0.51 parts by weight of the reinforcing material was obtained with respect to 00 parts by weight.

(Example 3) Regarding the surface treatment of the reinforcing material containing colloidal silica, the reinforcing material was dipped in a 2 wt% solution of the product number KBM573 manufactured by Shin-Etsu Chemical Co., Ltd. and passed through a squeezing roll. By heat-treating at 110 ° C. for 5 minutes, the amount of the surface treatment agent attached to the reinforcing material is 100 parts by weight of the reinforcing material containing the inorganic particles after the surface treatment.
Except that the reinforcing material is 0.91 parts by weight,
The same operation as in Example 1 was performed to obtain a substrate (composite material).

(Example 4) Regarding the surface treatment of the reinforcing material containing colloidal silica, the reinforcing material was immersed in a 0.01 wt% solution of the product number KBM573 manufactured by Shin-Etsu Chemical Co., Ltd. and passed through a squeezing roll. After that, by heat treating at 110 ° C. for 5 minutes, the amount of the surface treatment agent attached to the reinforcing material is
A substrate (composite material) was prepared in the same manner as in Example 1 except that 0.03 parts by weight of the reinforcing material was used to obtain 100 parts by weight of the reinforcing material containing the inorganic particles after the surface treatment.
I got

(Example 5) Regarding the surface treatment of the reinforcing material containing colloidal silica, the reinforcing material was immersed in a 4 wt% concentration solution of the product number KBM573, manufactured by Shin-Etsu Chemical Co., Ltd., and passed through a squeezing roll. By heat-treating at 110 ° C. for 5 minutes, the amount of the surface treatment agent attached to the reinforcing material is 100 parts by weight of the reinforcing material containing the inorganic particles after the surface treatment.
A substrate (composite material) was obtained in the same manner as in Example 1 except that the reinforcing material was 1.6 parts by weight.

(Example 6) Concerning the surface treatment of the reinforcing material containing colloidal silica, the concentration of γ-methacryloxypropyltrimethoxysilane (methacrylsilane coupling agent) manufactured by Shin-Etsu Chemical Co., Ltd., product number KBM503 is 1 After immersing in the wt% solution and passing through a squeeze roll,
By heat treatment at 0 ° C. for 5 minutes, the amount of the surface treatment agent attached to the reinforcing material is such that the reinforcing material 1 containing inorganic particles after the surface treatment
A substrate (composite material) was obtained in the same manner as in Example 1 except that 0.53 parts by weight of the reinforcing material was obtained with respect to 00 parts by weight.

(Example 7) Concerning the surface treatment of the reinforcing material containing colloidal silica, the concentration 2 of γ-methacryloxypropyltrimethoxysilane (methacrylsilane coupling agent) manufactured by Shin-Etsu Chemical Co., Ltd., product number KBM503. After immersing in the wt% solution and passing through a squeeze roll,
By heat treatment at 0 ° C. for 5 minutes, the amount of the surface treatment agent attached to the reinforcing material is such that the reinforcing material 1 containing inorganic particles after the surface treatment
A substrate (composite material) was obtained by performing the same operation as in Example 1 except that 0.92 parts by weight of the reinforcing material was obtained with respect to 00 parts by weight.

(Example 8) Regarding surface treatment of a reinforcing material containing colloidal silica, N-phenyl-γ-aminopropyltrimethoxysilane (aminosilane coupling agent) manufactured by Shin-Etsu Chemical Co., Ltd., product number KBM573 was used. Immersion in a mixed solution of a 1 wt% concentration solution and a 1 wt% concentration solution of γ-methacryloxypropyltrimethoxysilane (methacrylsilane-based coupling agent) manufactured by Shin-Etsu Chemical Co., Ltd., product number KBM503, and passed through a squeezing roll. After doing
By heat-treating at 110 ° C. for 5 minutes, the amount of the surface treatment agent attached to the reinforcing material is 0.92 parts by weight with respect to 100 parts by weight of the reinforcing material containing the inorganic particles after the surface treatment. A substrate (composite material) was obtained by performing the same operations as in Example 1 except that

Comparative Example 1 A substrate (composite material) was obtained in the same manner as in Example 1 except that the surface treatment of the reinforcing material containing colloidal silica was omitted.

(Comparative Example 2) Regarding the surface treatment of the reinforcing material containing colloidal silica, the reinforcing material was an aqueous solution of γ-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., product number KBM403) at a concentration of 1% by weight. After being dipped and passed through a squeeze roll, heat treatment was performed at 110 ° C. for 5 minutes, so that the amount of the surface treatment agent attached to the reinforcing material was 0.1% with respect to 100 parts by weight of the reinforcing material containing the inorganic particles after the surface treatment. Except that the surface-treated reinforcing material, which is 61 parts by weight, is obtained.
The same operation as in Example 1 was performed to obtain a substrate (composite material).

The amount of the surface-treating agent adhering to the reinforcing material in each of the above-mentioned Examples and Comparative Examples was measured as follows. First, the reinforcing material containing the inorganic particles after the surface treatment is dried at 90 ° C. for 1 hour to remove water. Next, after measuring the weight of the reinforcing material from which the water is removed, the reinforcing material is heat-treated at 300 ° C. for 2 hours, the weight is measured again, and the weight reduced by the heat treatment at 300 ° C. for 2 hours. To calculate. The weight reduced by this heat treatment is regarded as the weight of components other than Si of the silane-based compound, and the amount of the surface-treatment agent attached is calculated based on this weight and the structural formula of the silane-based coupling agent used as the raw material. By doing so, the amount of the surface treatment agent attached to the reinforcing material was determined.

Further, with respect to the substrates obtained in each of the examples and the comparative examples, an insulation resistance test after moisture absorption treatment and a solder heat resistance test after moisture absorption treatment were conducted as follows, and the results are shown in Table 1. . Regarding insulation resistance after moisture absorption treatment, JIS
Insulation resistance after immersion in boiling water at 100 ° C. for 2 hours was measured according to C6481. Regarding the solder heat resistance after the moisture absorption treatment, the sample was exposed to saturated steam at 135 ° C. for 2 hours (PCT treatment), and then immediately immersed in a solder bath at 260 ° C. for 60 seconds to examine whether blistering occurred. This test was conducted on 5 samples. When all 5 did not blister. ○ When all 5 blistered, x. No blistered and blistered in 5 bulges. In the case where the materials and the materials are mixed, it is shown as Δ in Table 1.

[0042]

[Table 1]

From the results shown in Table 1, it was confirmed that in the examples of the present invention, substrates having excellent insulation resistance after the moisture absorption treatment and solder heat resistance after the moisture absorption treatment were obtained as compared with the comparative examples.

[0044]

According to the inventions of claims 1 to 3, a reinforcing material containing inorganic particles having an average particle diameter of 1000 nm or less before being impregnated with a varnish is used as an aminosilane coupling agent and / or
Alternatively, since the surface treatment is performed using a surface treatment agent containing a methacrylsilane-based coupling agent, according to the inventions of claims 1 to 3, a varnish containing PPO, triallyl isocyanurate and a styrene butadiene copolymer is prepared. It is possible to obtain a composite material manufactured by using the composite material, which has a small coefficient of thermal expansion and is excellent in insulation resistance after moisture absorption treatment and solder heat resistance after moisture absorption treatment.

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area C08K 5: 3477 7:14 9:06

Claims (3)

[Claims] 1. A reinforcing material composed of strands formed by bundling monofilaments, containing inorganic particles having an average particle diameter of 1000 nm or less at a ratio of 1 to 30 parts by weight with respect to 100 parts by weight of the reinforcing material. In a method for producing a composite material, in which a reinforcing material containing particles is impregnated with a varnish containing polyphenylene oxide, triallyl isocyanurate and a styrene-butadiene copolymer, and dried to obtain a prepreg, and then the prepreg is molded to produce a composite material, A composite material characterized in that a reinforcing material containing inorganic particles before being impregnated with a varnish is surface-treated using a surface treating agent containing an aminosilane coupling agent and / or a methacrylsilane coupling agent. Manufacturing method. 2. The surface treatment of a reinforcing material containing inorganic particles is carried out such that the amount of the surface treatment agent attached to the reinforcing material is 0.05 to 1% with respect to 100 parts by weight of the reinforcing material containing inorganic particles after the surface treatment. The method for producing a composite material according to claim 1, wherein the amount is 0 part by weight. 3. The reinforcing material composed of strands formed by bundling monofilaments is glass cloth, and the material of the inorganic particles having an average particle diameter of 1000 nm or less is silica, according to claim 1 or 2. Composite material manufacturing method.