JP2008050526A - Resin composition, prepreg and laminated board using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition which contains PPE resin particles, an epoxy resin, a curing agent and an inorganic filler, in which the PPE particles are uniformly dispersed in the epoxy resin and which has a low dielectric constant, and to provide, using the composition, a prepreg excellent in impregnation property and a laminated board excellent in moldability, moisture absorption resistance and heat resistance. <P>SOLUTION: The resin composition contains (A) polyphenylene ether resin particles having an average particle size of 10-50 μm and a number average mol. wt. of 1,000-3,000, (B) an epoxy resin, (C) a curing agent and (D) an inorganic filler. The prepreg is prepared by impregnating a base material with the resin composition and semicuring the resultant composition. The laminated board is prepared by pressurizing the prepreg and a metal foil under heat, to form a laminate. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a laminate which is a material of a printed wiring board such as a multilayer printed wiring board used in an electronic device, a prepreg used in the production of the laminated board, and a resin composition used in the production of the prepreg. .

  A prepreg is prepared by impregnating a base material such as a glass cloth with a varnish of a thermosetting resin composition containing a polyphenylene ether resin (hereinafter sometimes referred to as “PPE”), an epoxy resin and a curing agent. It has been conventionally performed to obtain a laminate using A laminate obtained from a prepreg using this PPE-epoxy resin-based thermosetting resin composition exhibits excellent high-frequency characteristics, in particular, a constant dielectric constant and a dielectric loss tangent in a wide temperature range and humidity range. It has the characteristic that the tangent is small. Therefore, this laminate is preferably used in the X band (10 GHz) region used in the satellite communication wave region.

  In the laminate obtained by using this PPE-epoxy resin-based thermosetting resin composition, a cured product in which PPE and the epoxy resin are cross-linked is formed by reacting the terminal hydroxyl group of PPE with the epoxy group of the epoxy resin. Is done.

  For example, by redistributing a high molecular weight PPE and a phenol compound in the presence of a radical reaction initiator, a modified phenol compound in which a low molecular weight PPE and a phenol compound are condensed is generated and used as a PPE resin. There is a technique for manufacturing a laminated plate (Patent Document 1). In this laminated board, the phenolic hydroxyl group present at the end of the modified phenol compound used as the PPE resin reacts with the epoxy group in the epoxy resin to form a strong cross-linked structure. Therefore, this laminated board has the characteristic that it is hard to produce delamination and is excellent in heat resistance.

  However, high molecular weight PPE has poor solubility, and as a solvent used for the redistribution reaction in the presence of a radical reaction initiator, an aromatic hydrocarbon solvent such as benzene or toluene, or a halogen such as chloroform. It was necessary to use an unfavorable solvent in view of environmental problems such as a hydrofluoric solvent.

  In addition, a filler such as an inorganic filler or an organic filler is added to a resin composition used for manufacturing a laminated board, which is a material for a multilayer printed wiring board, in order to impart various characteristics. For example, an inorganic filler is added to increase the strength of the laminate. However, in the laminate obtained by using the above PPE-epoxy resin-based resin composition, a rigid cross-linked structure is formed by the resin composition itself, and therefore the rigidity further increases when a filler is added. There was a problem that it became brittle by the amount and the crack resistance during the subsequent processing was lowered.

Furthermore, since the filler generally added to the PPE-epoxy resin-based resin composition has a high dielectric constant, there is a problem that the original characteristic of the PPE resin, which is excellent in dielectric characteristics, is impaired.
Patent No. 3339301

  Under such circumstances, an object of the present invention is a resin composition containing a PPE resin, an epoxy resin, a curing agent, and an inorganic filler without using a modified phenol compound as the PPE resin. , PPE resin is uniformly dispersed in an epoxy resin, providing a resin composition having a low dielectric constant.

  Another object of the present invention is to provide a prepreg excellent in impregnation property and a laminate excellent in moldability, moisture absorption resistance and heat resistance using this resin composition.

  One aspect of the present invention that solves the above problems includes (A) polyphenylene ether resin particles having an average particle diameter of 10 to 50 μm and a number average molecular weight of 1000 to 3000, (B) an epoxy resin, (C) a curing agent, and ( D) A resin composition containing an inorganic filler. According to the above configuration, a resin composition in which the PPE resin is uniformly dispersed in the epoxy resin as particles in the resin composition, has excellent viscosity, and has excellent strength, moisture absorption resistance and heat resistance after curing. .

  The content of the (A) polyphenylene ether resin particles is preferably 30 to 80 parts by mass in 100 parts by mass of the total amount of (A) polyphenylene ether resin particles, (B) epoxy resin and (C) curing agent. According to the above configuration, it is possible to form a sea-island structure in which particles of PPE resin are uniformly dispersed in the epoxy resin, and thus it is possible to relieve thermal and mechanical stress.

  The inorganic filler (D) preferably has a relative dielectric constant of 3 or less. According to the above configuration, a resin composition having a low dielectric constant can be obtained without impairing the excellent dielectric properties inherently possessed by the PPE resin.

  And content of the said (D) inorganic filler is 60-120 mass parts with respect to 100 mass parts of total amounts of (A) polyphenylene ether resin particle, (B) epoxy resin, and (C) hardening | curing agent. Is preferred. According to the said structure, sufficient rigidity and favorable moldability and heat resistance are provided to the laminated board obtained using the said resin composition.

  Moreover, the prepreg obtained by impregnating the base material with the varnish of the resin composition, drying and semi-curing is excellent in handling property and impregnation property. Furthermore, when the base material is impregnated with the resin composition, it is not necessary to use an aromatic hydrocarbon solvent or a halogenated hydrocarbon solvent used for preparing the modified phenol compound.

  The substrate is preferably a glass woven fabric or a nonwoven fabric. According to the said structure, the laminated board excellent in mechanical strength is obtained.

  Moreover, it is preferable to contain 60-75 mass% of total amounts of (A) polyphenylene ether resin particle, (B) epoxy resin, and (C) hardening | curing agent in a prepreg. According to the said structure, the laminated board with favorable moldability after lamination | stacking shaping | molding of a prepreg is obtained.

  And the laminated board excellent in a moldability, moisture absorption resistance, and heat resistance is obtained by heat-pressing the said prepreg and metal foil, and carrying out lamination molding.

  According to the present invention, a resin composition having a low dielectric constant and good strength after curing, moisture absorption resistance and heat resistance can be obtained. Using the resin composition of the present invention, without using an aromatic hydrocarbon solvent or a halogenated hydrocarbon solvent, a prepreg excellent in impregnation into a substrate and excellent moldability, moisture absorption resistance and heat resistance A laminated board is obtained.

  As described above, one aspect of the present invention is that (A) polyphenylene ether resin particles having an average particle diameter of 10 to 50 μm and a number average molecular weight of 1000 to 3000, (B) an epoxy resin, (C) a curing agent, and ( D) A resin composition containing an inorganic filler.

  (A) The polyphenylene ether resin (PPE resin) is a homopolymer or copolymer of a phenol derivative, or a copolymer of a phenol derivative and another monomer as long as it has a so-called polyphenylene ether as a main skeleton. And what is used as an electronic equipment component material can be especially used without a restriction | limiting. Examples of such PPE resin include poly (2,6-dimethyl-1,4-phenylene oxide). Moreover, PPE resin which substituted the methyl group of PPE with the allyl group, the epoxy group, the vinyl group etc. can also be used, for example.

  PPE resin particles having a volume-based average particle diameter in the range of 10 to 50 μm are used. When the average particle size is less than 10 μm, the viscosity of the resin varnish in which the resin composition is dissolved in the solvent is increased, the impregnation property to the substrate is lowered, and the handleability of the resulting prepreg is deteriorated. On the other hand, when the average particle diameter exceeds 50 μm, the particles of the PPE resin are difficult to uniformly disperse in the epoxy resin and may settle in the epoxy resin. In addition, it is preferable to use what has an average particle diameter in the range of 20-40 micrometers as a PPE resin particle. The average particle diameter can be measured with a laser diffraction particle size distribution measuring apparatus. The average particle diameter of the PPE resin particles used can be adjusted by dispersing in an organic solvent such as methyl ethyl ketone and filtering.

  In addition, PPE resin particles having a number average molecular weight in the range of 1000 to 3000 are used. When the number average molecular weight is less than 1000, the mechanical strength and heat resistance of the cured product are likely to decrease when the resin composition is cured. When the number average molecular weight exceeds 3000, the melt viscosity of the semi-cured product increases when the resin composition is semi-cured, and the peel strength of the metal foil of the laminate, solder heat resistance, plating penetration, etc. Is easily disturbed. The PPE resin particles preferably have a number average molecular weight in the range of 1500 to 2500.

  It is preferable that content of PPE resin particle is 30-80 mass parts in 100 mass parts of total amounts of the resin component containing PPE resin particles, an epoxy resin, and a hardening | curing agent. If it is less than 30 parts by mass, the original characteristic of the PPE resin that is excellent in dielectric characteristics is not utilized, and it becomes difficult to obtain a laminate having sufficient dielectric characteristics. If it exceeds 80 parts by mass, it will be difficult to form a sea-island structure in which the particles of PPE resin are uniformly dispersed in the epoxy resin, which tends to adversely affect the curing system of the resin composition. In addition, it is more preferable that content of PPE resin particle is 40-70 mass parts in 100 mass parts of total amounts of the resin component containing PPE resin particles, an epoxy resin, and a hardening | curing agent.

  (B) The epoxy resin should just be an epoxy resin which has 2 or more of epoxy groups in a molecule | numerator, Generally a well-known thing can be used. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, isocyanurate type epoxy resin, hydantoin type epoxy resin, alicyclic epoxy resin, biphenyl Type epoxy resin, polyfunctional epoxy resin, and the like. These epoxy resins can be used alone or in combination of two or more. Moreover, the flame retardant epoxy resin which brominated these resin can also be used. An epoxy resin having one epoxy group in the molecule can be used in combination.

  (C) As a hardening | curing agent, what was generally used conventionally can be used, and if it can be used as a hardening | curing agent of the said epoxy resin, there will be no restriction | limiting in particular. Examples thereof include amine-based curing agents such as primary amines and secondary amines, phenol-based curing agents such as bisphenol A and bisphenol F, and acid anhydride-based curing agents. These curing agents can be used alone or in combination of two or more.

  The curing agent is preferably blended in an equivalent ratio of 0.05 to 0.2 equivalents with respect to the epoxy resin.

  In order to accelerate the curing reaction of the resin composition, it is also preferable to add a curing accelerator as necessary to the curing agent. Examples of the curing accelerator include imidazoles such as 2-ethyl-4-methylimidazole, tertiary amines such as triethylenediamine, organic phosphines such as tributylphosphine, and tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate. 2 or more types may be used in combination.

  (D) The inorganic filler is not particularly limited as long as it has insulating properties, and may be selected according to the property to be imparted to the resin composition. However, it is an inorganic filler having a relative dielectric constant of 3 or less. Is preferred. When the relative dielectric constant of the inorganic filler exceeds 3, the excellent dielectric properties inherently possessed by the PPE resin are impaired, and the dielectric properties of the laminate are liable to be adversely affected. Examples of such inorganic fillers include boron nitride, silica, talc, calcined talc, aluminum hydroxide, magnesium hydroxide, kaolin, and alumina. In particular, hexagonal boron nitride has a relative dielectric constant of 1.6 and can be preferably used. An inorganic filler may be used independently or may use 2 or more types together.

  When boron nitride having a low dielectric constant and another inorganic filler are used in combination as the inorganic filler, it is preferable to use silica having a substantially spherical particle shape as the other inorganic filler. In particular, it is preferable to use fused silica having a substantially spherical shape as silica. Use of non-spherical silica such as crushed silica may lead to deterioration of the flowability of the resin composition and the drill wear rate. Moreover, when other metal fillers such as aluminum hydroxide and magnesium hydroxide are used in combination as the other inorganic fillers, the dielectric constant of the resulting laminate may increase, which is not preferable. Furthermore, when talc and clay (aluminum silicate) are used together in large quantities, the water absorption rate of the cured resin increases, which tends to cause performance deterioration.

  It is preferable that content of an inorganic filler is 60-120 mass parts with respect to 100 mass parts of total amounts of the resin component containing a polyphenylene ether resin particle, an epoxy resin, and a hardening | curing agent. If the amount is less than 60 parts by mass, the rigidity of the resulting laminated plate tends to be insufficient. When it exceeds 120 parts by mass, the crack resistance at the time of molding the laminated plate is impaired, so that burrs and voids are likely to occur, and the heat resistance tends to be lowered.

  The particle size of the inorganic filler is preferably in the range of 0.2 to 3 μm. By making the particle size of the inorganic filler within this range, the drill wear rate and breakage can be improved as compared with the case of adding a large particle size, and good flowability of the resin composition can be obtained. It is possible to reduce scraping during molding.

  The inorganic filler is preferably subjected to a surface treatment with a coupling agent on the surface thereof. By this surface treatment, the adhesion at the interface between the cured resin and the inorganic filler particles is improved, and moisture absorption that causes an increase in dielectric constant can be prevented. As a coupling agent, a general silane compound can be used. For example, vinyl silane, epoxy silane, methacryloxy silane, cationic silane compound, etc. can be used.

  In the surface treatment, it is preferable to add 0.5 to 2 parts by mass of the silane coupling agent with respect to 100 parts by mass of the inorganic filler before the surface treatment. If the amount of the silane coupling agent is small, sufficient adhesion between the resin and the inorganic filler may not be obtained during molding of the laminate, whereas if it is large, the heat resistance of the laminate after molding may be insufficient. May decrease.

  The surface treatment method of the inorganic filler is not particularly limited, but is preferably a wet method because the surface needs to be uniformly treated. Specifically, an inorganic filler is added to the silane coupling agent solution to form a slurry or soak, and then dried by heating.

  The resin composition according to the present embodiment adds the inorganic filler to the resin component including the PPE resin particles, the epoxy resin, and the curing agent, and blends other components as necessary, and then a disper, a mill, and the like. Can be prepared by mixing uniformly.

  And the prepreg which concerns on this embodiment is manufactured by making the base material impregnate the said resin composition, and drying by heating after that, and then semi-hardening the resin composition in a base material to a B-stage state. be able to.

  For impregnating the substrate with the resin composition, a known method can be employed. For example, the resin composition may be dissolved in an organic solvent to prepare a resin varnish, and the substrate may be impregnated with the resin varnish. Examples of the organic solvent used here include ketones such as methyl ethyl ketone, and alcohols. These organic solvents can be used alone or in combination of two or more. In this embodiment, since a modified phenol compound is not used as the PPE resin contained in the resin composition, an aromatic hydrocarbon solvent such as toluene or chloroform used when preparing the modified phenol compound is used. It is not necessary to use a halogenated hydrocarbon solvent.

  Examples of the substrate include glass cloth, aramid cloth, polyester cloth, glass nonwoven fabric, aramid nonwoven fabric, polyester nonwoven fabric, pulp paper, linter paper and the like. When a glass cloth is used, a laminate having excellent mechanical strength can be obtained, and a flat glass processed glass cloth is particularly preferable. The flattening can be performed, for example, by continuously pressing the glass cloth with a press roll with an appropriate pressure and compressing the yarn flatly. In addition, as a thickness of a base material, the thing of 0.04-0.3 mm can generally be used.

  The heating conditions for drying and semi-curing can be appropriately set depending on the composition of the resin composition, etc., and can be, for example, 150 to 170 ° C. for 4 to 7 minutes.

  The resin content in the prepreg may be appropriately set according to the thickness of the base material and the purpose of use. However, when glass cloth is used as the base material, the dielectric constant of the glass is larger than that of the resin. Increasing the value is advantageous in terms of dielectric characteristics. The prepreg preferably contains 60 to 75 mass% of the total amount of the resin components including the PPE resin, the epoxy resin, and the curing agent. By setting the resin content in the prepreg within this range, a laminate having good moldability after the prepreg is laminated is obtained.

  The laminated board which concerns on this embodiment can be formed using metal foils, such as said prepreg and copper foil. One or a plurality of prepregs can be used, and after a metal foil is stacked on one or both sides of this prepreg, the resin composition of the prepreg is cured by heating and pressing to form an insulating layer. In addition, a single-sided or double-sided metal foil-clad laminate can be formed by integrating the metal foil and the insulating layer by curing the resin composition.

  The heating and pressurizing conditions at the time of laminate molding can be appropriately set depending on the thickness of the laminate to be produced, the type of the resin composition of the prepreg, etc. 4.0 Pa and time can be 120 to 150 minutes.

  A printed wiring board is formed by forming holes for through-holes by drilling or carbon dioxide gas laser, through-hole plating, or circuit formation by a subtractive method on the obtained laminated board be able to.

  Hereinafter, the present invention will be described in more detail by way of examples, but the scope of the present invention is not limited thereto.

Example 1
A resin composition was prepared with the formulation shown in Table 1. The resin composition was prepared by mixing a resin component containing polyphenylene ether (PPE) resin particles, an epoxy resin, and a curing agent (including a curing accelerator) and an inorganic filler.

  As the PPE resin particles, those having a number average molecular weight of 2000 and an average particle diameter of 20 μm were used. 40 parts by mass of PPE resin particles, 30 parts by mass of brominated bisphenol A type epoxy resin (“EPPN501H” manufactured by Nippon Kayaku) and 28.5 parts by mass of phenol novolac type epoxy resin (Asahi Ciba) “EPN1182”), 1 part by weight of diaminodiphenylmethane (“Etacure” manufactured by Japan Epoxy Resin) as a curing agent, 0.5 part by weight of 2-ethyl-4-methyl-imidazole (manufactured by Shikoku Chemicals) as a curing accelerator ) Was used as a resin component. Examples of inorganic fillers include 40 parts by mass of hexagonal boron nitride and 80 parts by mass of surface-treated silica (Adaptex synthetic silica having an approximately spherical particle size and an average particle size of 0.5 μm). A ring-treated product (hereinafter sometimes referred to as “silica A”) was used in combination.

  A resin varnish was prepared by dissolving 100 parts by mass of the resin composition containing the resin component and the inorganic filler in 90 parts by mass of methyl ethyl ketone (MEK), and impregnating the resin varnish into a glass cloth having a thickness of 80 μm. The glass cloth impregnated with the resin varnish was heated and dried, and the resin composition was semi-cured to prepare a prepreg having a resin component content of 60% by mass.

  Next, a plurality of the above prepregs are stacked, and a copper foil having a thickness of 18 μm is stacked on both outer sides of these prepregs, and this is heated and pressed under conditions of a temperature of 200 ° C., a pressure of 3.5 MPa, and a time of 120 minutes. Thus, a double-sided copper-clad laminate having a thickness of 1.0 mm was produced.

Example 2
A resin composition was prepared in the same manner as in Example 1 except that only 120 parts by mass of hexagonal boron nitride was used as the inorganic filler, and a prepreg and a double-sided copper-clad laminate were produced using this resin composition. .

Example 3
A resin composition was prepared in the same manner as in Example 1 except that a PPE resin particle having a number average molecular weight of 1000 was used, and a prepreg and a double-sided copper-clad laminate were produced using the resin composition.

Example 4
A resin composition was prepared in the same manner as in Example 1 except that PPE resin particles having an average particle diameter of 50 μm were used, and prepregs and double-sided copper-clad laminates were produced using the resin compositions.

Example 5
A prepreg was prepared in the same manner as in Example 1 except that a glass cloth was impregnated with a resin varnish so that the resin component content in the prepreg was 75% by mass, and the resin composition was semi-cured to prepare a prepreg. And the double-sided copper clad laminated board was produced.

Example 6
A resin composition was prepared in the same manner as in Example 1 except that only 60 parts by mass of hexagonal boron nitride was used as the inorganic filler, and a prepreg and a double-sided copper-clad laminate were produced using this resin composition. .

Example 7
As an inorganic filler, instead of 80 parts by mass of surface-treated silica (silica A), 40 parts by mass of silica A and 40 parts by mass of non-surface-treated silica (particle size is almost spherical and average particle size is 0.5 μm) A resin composition prepared in the same manner as in Example 1 except that a mixture with Admatex synthetic silica, which is not subjected to surface treatment, may be referred to as “silica B” in the following. Using this, a prepreg and a double-sided copper-clad laminate were produced.

Example 8
A resin composition was prepared in the same manner as in Example 1 except that 70 parts by mass of PPE resin particles and 28.5 parts by mass of a phenol novolac type epoxy resin were used as the epoxy resin. A double-sided copper-clad laminate was produced.

Example 9
A resin composition was prepared in the same manner as in Example 1 except that only 140 parts by mass of hexagonal boron nitride was used as the inorganic filler, and a prepreg and a double-sided copper-clad laminate were produced using this resin composition. .

Example 10
A prepreg was prepared in the same manner as in Example 1 except that a resin cloth varnish was impregnated into a glass cloth so that the content of the resin component in the prepreg was 80% by mass, and the resin composition was semi-cured to prepare a prepreg. And the double-sided copper clad laminated board was produced.

Comparative Example 1
A high molecular weight PPE and a phenol compound were redistributed in the presence of a radical reaction initiator to produce a modified phenol compound obtained by condensing a low molecular weight PPE and a phenol compound, and this was used as a PPE resin.

  The modified phenol compound is obtained by mixing 100 parts by mass of high molecular weight PPE (molecular weight: about 15000, made by Japan GE Plastics) and 3.5 parts by mass of bisphenol A (phenol compound) by heating and melting in a toluene solvent. It was prepared by blending 4.5 parts by mass of benzoyl peroxide (a radical initiator made by NOF Corporation) and causing a redistribution reaction. 40 parts by mass of the modified phenolic compound obtained, 40 parts by mass of brominated bisphenol A type epoxy resin (“EPPN501H” manufactured by Nippon Kayaku) and 18.5 parts by mass of phenol novolac type epoxy resin as epoxy resins ("EPN1182" manufactured by Asahi Ciba), 1 part by mass of diaminodiphenylmethane ("Etacure" manufactured by Japan Epoxy Resin) as a curing agent, and 0.5 part by mass of 2-ethyl-4-methyl-imidazole (as a curing accelerator) Shikoku Kasei) and 60 parts by mass of non-surface-treated silica (silica B) as an inorganic filler were used as a resin composition.

  A resin varnish is prepared by dissolving 100 parts by mass of this resin composition in 100 parts by mass of toluene, impregnating the resin varnish into a glass cloth having a thickness of 80 μm, and heating the glass cloth to semi-cure the resin composition. Thus, a prepreg having a resin component content of 60% by mass was produced.

  A plurality of the above prepregs are overlaid, and a copper foil having a thickness of 18 μm is overlaid on both outer sides of these prepregs, and this is heated and pressed under conditions of a temperature of 200 ° C., a pressure of 3.5 MPa, and a time of 120 minutes, A double-sided copper-clad laminate with a thickness of 1.0 mm was produced.

Comparative Example 2
A resin composition was prepared in the same manner as in Example 1 except that a PPE resin particle having a number average molecular weight of 4000 was used, and a prepreg and a double-sided copper-clad laminate were produced using the resin composition.

Comparative Example 3
Except for using PPE resin particles having an average particle diameter of 100 μm, a resin composition was prepared in the same manner as in Example 1, and a prepreg and a double-sided copper-clad laminate were produced using the resin composition.

Comparative Example 4
Except for using PPE resin particles having an average particle diameter of 5 μm, a resin composition was prepared in the same manner as in Example 1, and a prepreg and a double-sided copper-clad laminate were prepared using the resin composition.

Test Example About the resin varnishes prepared in Examples 1 to 10 and Comparative Examples 1 to 4 above, the initial viscosity and storage stability were evaluated, and the prepreg produced was further evaluated for appearance, handleability and impregnation. The copper clad laminate was evaluated for formability, glass transition temperature, water absorption, relative permittivity, and heat resistance.

  The resin varnish was measured for the initial viscosity after preparation at a solid content of 60% by mass, and evaluated as “◯” when the viscosity was 120 to 200 cps and “X” when it exceeded 200 cps. Moreover, the preservability of the resin varnish was evaluated as “◯” when the uniform dispersion of the resin composition was maintained, and “X” when aggregation occurred.

  The appearance of the prepreg was visually observed and evaluated as “◯” when no irregularities were generated and “X” when many irregularities were generated. Moreover, the handleability of the prepreg was evaluated as ○ when the powder did not fall off from the surface, and × when the powder had fallen off from the surface. The impregnation property of the prepreg was evaluated as ◯ when the resin did not peel off from the base material, and x when the resin peeled off from the base material occurred.

  The moldability of the double-sided copper-clad laminate is determined by removing the copper foil on the surface by etching, observing the surface of the laminate and the presence or absence of voids in the cross section of the laminate. A case having a small amount of void was evaluated as Δ, and a case having a lot of voids and voids was evaluated as ×. Moreover, the glass transition temperature measured the glass transition point (Tg) using the DMA measuring apparatus as a formability parameter | index. The water absorption rate of the double-sided copper-clad laminate is an index of hygroscopicity, where the copper foil on the surface of the obtained double-sided copper-clad laminate is removed by etching, cut into 50 mm squares, and a pot with a temperature of 121 ° C and a humidity of 100%. The weight increase value before and after 300 hours was measured. Moreover, the dielectric constant measured the dielectric characteristic in 1 GHz of a double-sided copper clad laminated board based on JISC6481. Furthermore, the heat resistance is obtained by cutting the obtained double-sided copper-clad laminate into a size of 50 mm × 50 mm and placing it in an oven at 260 ° C. for 1 hour, and then observing the peeling of the copper foil. Those with no were evaluated as x.

  The results are shown in Table 1.

  As shown in Examples 1 to 8, it was prepared from a resin composition containing PPE resin particles having an average particle diameter of 10 to 50 μm and a number average molecular weight of 1000 to 3000, an epoxy resin, a curing agent, and an inorganic filler. The resin varnish has good initial viscosity and storage stability, and the prepreg produced using this resin is excellent in appearance, handleability and impregnation, and the obtained double-sided copper-clad laminate has excellent moldability and resistance. It can be seen that it is excellent in hygroscopicity, dielectric properties and heat resistance.

  In addition, in the resin composition (Example 9) with a large content of the inorganic filler, the initial viscosity and storage stability of the obtained resin varnish were insufficient as compared with those in Example 2. It can also be seen that the laminate (Example 10) obtained from the prepreg having a high resin component content is slightly inferior in moldability and moisture absorption resistance to that of Example 5.

  In particular, the water absorption rate of the double-sided copper-clad laminates obtained in Examples 1 to 10 is 0.6 to 1 in terms of the weight increase rate measured after 300 hours under the above conditions, that is, at a temperature of 121 ° C. and a humidity of 100%. When compared with that of Comparative Example 1 (1.2%) using a modified phenolic compound as a PPE resin, it was found that a laminate having excellent moisture absorption resistance was obtained.

  On the other hand, the laminate (Comparative Example 2) obtained from the resin composition using PPE resin particles having a large number average molecular weight did not have sufficient moldability. In a resin composition using PPE resin particles having a large average particle size (Comparative Example 3) and PPE resin particles having a small average particle size (Comparative Example 4), most evaluations of the resulting resin varnish, prepreg and laminate are unsatisfactory. It was something.

Claims (8)

  (A) A resin composition containing polyphenylene ether resin particles having an average particle diameter of 10 to 50 μm and a number average molecular weight of 1000 to 3000, (B) an epoxy resin, (C) a curing agent, and (D) an inorganic filler.   The content of the (A) polyphenylene ether resin particles is 30 to 80 parts by mass in 100 parts by mass of the total amount of (A) polyphenylene ether resin particles, (B) epoxy resin and (C) curing agent. The resin composition as described.   The resin composition according to claim 1, wherein the (D) inorganic filler has a relative dielectric constant of 3 or less.   The content of the (D) inorganic filler is 60 to 120 parts by mass with respect to 100 parts by mass as a total of (A) polyphenylene ether resin particles, (B) epoxy resin, and (C) curing agent. The resin composition described in 1.   A prepreg obtained by impregnating a base material with the varnish of the resin composition according to claim 1, drying and semi-curing the base material.   The prepreg according to claim 5, wherein the substrate is a glass woven fabric or a nonwoven fabric.   The prepreg according to claim 5, wherein the prepreg contains 60 to 75 mass% of a total amount of (A) polyphenylene ether resin particles, (B) epoxy resin, and (C) a curing agent.   The laminated board obtained by heat-pressing the prepreg and metal foil in any one of Claims 5-7, and carrying out lamination molding.