JP4442174B2 - Flame-retardant resin composition, and prepreg, metal-clad laminate and printed wiring board using the same - Google Patents

Description

  The present invention relates to a resin composition excellent in flame retardancy, dielectric properties and moldability using a non-halogen flame retardant, and a prepreg, metal-clad laminate and printed wiring board using the same.

  Epoxy resins have excellent mechanical strength, heat resistance, adhesion, and electrical insulation, so they are used in many industrial fields such as paint, electricity, civil engineering, and adhesion, and many epoxy resins are also used in printed wiring boards. Yes. In order to ensure safety against fire, electric devices using these printed wiring boards are usually imparted with flame retardancy. In order to impart flame retardancy, brominated flame retardants such as tetrabromobisphenol A (hereinafter abbreviated as TBBA) have been used in the past.

  However, when a printed wiring board is disposed of by incineration, it is said that a halogen-based flame retardant such as a brominated flame retardant contained therein generates harmful dioxins due to combustion. Therefore, regulations are expected to be added to halogenated flame retardants in the future. For these reasons, non-halogen flame retardants such as phosphorus flame retardants and nitrogen flame retardants, inorganic fillers, and the like are used as flame retardants instead of halogen flame retardants.

  In addition, the printed wiring board has been improved in the epoxy resin that serves as the base of the resin composition in order to improve the dielectric properties typified by dielectric constant and dielectric loss tangent, in order to cope with the trend in electrical equipment with higher frequency. ing. For this purpose, it is known that a low dielectric material such as a cyanate compound (Patent Document 1), polyphenylene ether (hereinafter referred to as PPE) (Patent Document 2) is used together with an epoxy resin as a material for a printed wiring board.

JP-A-10-273532 JP 20007763 A

However, when trying to obtain flame retardancy with a non-halogen flame retardant, the amount of addition of phosphorus flame retardant, nitrogen flame retardant, and inorganic filler increases, resulting in a problem that the dielectric properties of the resin composition deteriorate. there were. Further, conventionally used PPE has poor compatibility with a solvent and a resin, so that the appearance of the prepreg is deteriorated and the moldability of the resin composition is lowered. For this reason, in a resin composition using a non-halogen flame retardant and using PPE, any of flame retardancy, dielectric properties, and moldability is lowered, resulting in flame retardancy, dielectric properties, moldability. There was a problem that it was difficult to obtain a laminate having an excellent property balance.
The object of the present invention is to have excellent flame retardancy and excellent dielectric properties typified by dielectric constant and dielectric loss tangent in spite of the resin composition using non-halogen flame retardant and PPE. Another object of the present invention is to provide a resin composition having excellent moldability. In addition, a prepreg using the resin composition has a good appearance, and provides a laminated board and a multilayer printed wiring board having an excellent balance of flame retardancy, dielectric characteristics, and moldability using the prepreg. is there.

The present invention includes (A) a non-halogenated epoxy group-containing compound having at least two epoxy groups in one molecule;
(B) a phenolic resin curing agent modified with a nitrogen compound, a hydroxyl group equivalent of 140 to 190, and a nitrogen content of 17.0% to 25.0%,
(C) a polyphenylene ether or modified polyphenylene ether having a number average molecular weight (Mn) of 1500 to 3500 and a weight average molecular weight (Mw) of 2500 to 7000,
(D) a phosphorus-containing flame retardant;
The present invention relates to a flame retardant resin composition.

  The resin composition of the present invention is a resin composition using a non-halogen flame retardant and using PPE, has excellent flame retardancy, and has excellent dielectric properties such as dielectric constant and dielectric loss tangent, Moreover, it is excellent in moldability. Moreover, the prepreg by the resin composition of this invention is excellent in an external appearance (moldability) in addition to being excellent in a flame retardance and a dielectric characteristic. Furthermore, a metal-clad laminate using the resin composition of the present invention and a printed wiring board using the same are excellent in the balance of flame retardancy, dielectric properties and moldability.

  (A) Non-halogenated epoxy compound having at least two epoxy groups in one molecule used in the present invention includes bisphenol A epoxy resin, bisphenol F epoxy resin, phenol novolac type epoxy resin, bisphenol A novolac type epoxy resin, A cresol novolac type epoxy resin and the like can be mentioned, but the cresol novolac type epoxy resin is not limited to these, and two or more types may be used simultaneously. In view of heat resistance and high glass transition temperature, novolak type epoxy resins such as phenol novolak type epoxy resin, bisphenol A novolak type epoxy resin, cresol novolak type epoxy resin and the like are preferable. In consideration of dielectric characteristics, it is preferable to use an epoxy resin such as a tetramethylbiphenyl type epoxy resin, a zylock type epoxy resin, a dicyclopentadiene type epoxy resin, or the like. Component (A) of the present invention is based on the total solid content of components (A), (B), (C), and (D) (total solid content of essential components in the resin composition not containing a filler), It is preferable to use 20 to 60% by weight, and it is more preferable to use 25 to 55% by weight.

The phenol resin curing agent modified with the nitrogen compound (B) used in the present invention is a resin curing agent having a hydroxyl group equivalent of 140 to 190 and a nitrogen content of 17.0% to 25.0%. Examples of the component (B) used in the present invention include phenol resins modified with nitrogen compounds such as melamine, benzoguanamine, acetoguanamine, and urea. The phenol resin may be either a novolak type or a resole type, and examples thereof include a phenol formaldehyde resin, a phenol furfural resin, and a resorcin-formaldehyde resin, and a novolac type phenol resin is preferable. As the component (B), melamine-modified novolac resins, benzoguanamine-modified novolak resin, acetoguanamine-modified novolac resins, urea-modified novolac resins are preferred, more preferably those which are melamine-modified, in addition to melamine-modified cresol [C ₆ H Those containing a ( ₄ (CH ₃ ) OH] skeleton are particularly preferred. The hydroxyl group equivalent of the component (B) is 140 to 190 in consideration of the balance between flame retardancy and dielectric properties due to the nitrogen content in the composition depending on the amount of the component (B) corresponding to the epoxy equivalent. Is preferred. Furthermore, the nitrogen content of the component (B) is preferably 17.0 to 25.0% by weight in consideration of the balance between flame retardancy and mechanical properties as a cured product, and 18.0 to 24. More preferably, it is 0% by weight. The component (B) of the present invention is preferably used in an amount of 10 to 40% by weight, preferably 10 to 30% by weight, based on the total solid content of the components (A), (B), (C) and (D). It is more preferable. Therefore, (B) component is mix | blended in the quantity from which nitrogen content will be 3.0 to 10.0 weight% with respect to the solid content total amount of (A), (B), (C), and (D) component. It is preferable to blend in an amount of 3.2 to 5.3% by weight.

  According to the present invention, it is not necessary to use a curing accelerator, but a curing accelerator may be optionally used to accelerate the curing of the resin. The type of curing accelerator is not particularly limited. For example, an imidazole compound, an organic phosphorus compound, a secondary amine, a tertiary amine, a quaternary ammonium salt, or the like is used, and two or more types are used in combination. The blending amount of the curing accelerator is not particularly limited. 0.01-10.0 weight part is preferable with respect to 100 weight part of resin which is a main material. As the curing accelerator to be used, imidazole compounds include imidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 1-benzyl-2-methylimidazole, 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 may be masked with a masking agent. Examples of the masking agent include acrylonitrile, phenylene diisocyanate, toluidine isocyanate, naphthalene diisocyanate, methylene bisphenyl isocyanate, and melamine acrylate.

  (C) Polyphenylene ether (PPE) or modified polyphenylene ether (modified PPE) used in the present invention preferably has a number average molecular weight (Mn) of 1500 to 3500 and a weight average molecular weight (Mw) of 2500 to 7000, More preferably, the number average molecular weight (Mn) is 1900 to 3500, and the weight average molecular weight (Mw) is 2500 to 5500. This takes into account factors such as changes in dielectric properties due to the hydroxyl group at the end due to the low molecular weight component of PPE, solder heat resistance, finish of coating on the prepreg due to compatibility with solvents and resins, appearance, etc. Is. When the component (C) is a modified PPE, the terminal can be epoxidized. In addition, the component (C) of the present invention is effective for improving the dielectric properties and filling the circuit due to the varnish viscosity with respect to the total solid content of the components (A), (B), (C) and (D). Considering the balance with the properties, it is preferable to use 1 to 30% by weight, and more preferably 2 to 25% by weight.

  When the component (C) is PPE, the number average molecular weight (Mn) is preferably 1500 to 3500, the weight average molecular weight (Mw) is preferably 2500 to 4500, the number average molecular weight (Mn) is 1900 to 2300, and The weight average molecular weight (Mw) is more preferably 2500 to 3000.

  When the component (C) is modified PPE and its terminal is epoxidized, the number average molecular weight (Mn) is preferably 1500 to 3500, and the weight average molecular weight (Mw) is preferably 4500 to 7000, and the number average More preferably, the molecular weight (Mn) is 3000 to 3500, and the weight average molecular weight (Mw) is 4500 to 5500. In the case of terminal epoxidized PPE, considering the balance between the main curing reaction of component (A) and component (B), solubility in solvent, resin, and reaction with resin, the epoxy equivalent is 800 It is preferable that it is -1200, and it is more preferable that it is 1000-1200.

  Examples of the phosphorus-containing flame retardant used in the present invention include triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, trimethyl phosphate, triethyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, resorcinol bis (diphenyl) ) In addition to phosphates such as phosphate, 2-ethylhexyl diphenyl phosphate, dimethylmethyl phosphate, triallyl phosphate, polyphosphates such as ammonium polyphosphate and polyphosphate amide, condensed phosphates, 9,10-dihydro- 9-oxa-10-phosphaphenanthrene-10-oxide or a derivative thereof, 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-10-phosphaphena Tren 10-oxide or derivatives thereof, dialkyl phosphinate metal salts and the like, flame retardant to be used is not limited thereto. The component (D) of the present invention is preferably used in an amount of 10 to 30% by weight, preferably 20 to 30% by weight, based on the total solid content of the components (A), (B), (C) and (D). It is more preferable. Furthermore, the component (D) contains phosphorus with respect to the total solid content of the components (A), (B), (C) and (D), considering the balance between flame retardancy, alkali resistance and heat resistance. It is preferable to mix | blend in the quantity used as the quantity used as 2.0-10.0 weight%, and it is more preferable to mix | blend in the quantity used as 2.5-2.8 weight%.

  In the present invention, the kind of inorganic filler is not particularly limited, and examples thereof include calcium carbonate, alumina, titanium oxide, mica, aluminum carbonate, aluminum hydroxide, magnesium silicate, aluminum silicate, silica powder, short glass fiber, Various whiskers such as aluminum borate whisker and silicon carbide whisker are used. Two or more of these may be used in combination. The compounding quantity of an inorganic filler will not be specifically limited if it exists in the range of 4 to 40 weight% with respect to the solid content total amount of a resin composition. However, since the dielectric constant tends to increase and the dielectric loss tangent tends to decrease in proportion to the amount of inorganic filler added, the blending amount is determined in consideration of these balances. In the case where emphasis is placed on lowering the dielectric constant, the blending amount of the inorganic filler is preferably 4 to 10% by weight with respect to the total solid content of the resin composition. In the case where emphasis is placed on lowering the dielectric loss tangent, the blending amount of the inorganic filler is preferably 10 to 35% by weight with respect to the total solid content of the resin composition. Furthermore, the addition of an inorganic filler brings about an improvement in flame retardancy and thermal expansion coefficient. In addition, when considering dielectric properties such as dielectric constant and dielectric loss tangent, silica is preferably used as the inorganic filler.

  In addition to the above components, the resin composition of the present invention optionally includes an antioxidant, a curing catalyst, a photochromic agent, a thermochromic inhibitor, a plasticizer such as p-toluenesulfonamide, a pigment, an antifoaming agent, and a flame retardant. , Stabilizers, adhesion-imparting agents, leveling agents, peeling accelerators, fragrances, imaging agents, thermal crosslinking agents, and the like can be added. These can be used alone or in combination of two or more.

The resin composition of the present invention has a total solid content of the components (A), (B), (C) and (D),
(A) component is 20 to 60% by weight,
Component (B) is 10 to 40% by weight
Component (C) is 1 to 30% by weight
Component (D) is 10 to 30% by weight
The total amount of solids of the components (A), (B), (C) and (D) is naturally 100% by weight, but this is (A), (B), (C ) And (D) are the ratios between the components, and other components are not included.
Further, the nitrogen content in the resin composition is 3.0 to 10.0% by weight and the phosphorus content is 2.0 to 10.0 with respect to the total solid content of the resin composition not including the filler. It is preferable that it is weight%. In some cases, an inorganic filler can be added, and the amount of the inorganic filler is preferably 4 to 40% by weight based on the total solid content of the resin composition.

  The resin composition of the present invention is preferably used after being diluted with a solvent to form a varnish. The type of the solvent used at this time is not particularly limited, and examples thereof include alcohol solvents such as methanol and ethanol, ether solvents such as ethylene glycol monomethyl ether, ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, N, Examples include amide solvents such as N-dimethylformamide, aromatic hydrocarbon solvents such as toluene and xylene, ester solvents such as ethyl acetate, and nitrile solvents such as butyronitrile. May be used. Moreover, there is no restriction | limiting in particular about the solid content density | concentration of a varnish, According to a resin composition, the kind of inorganic filler, a compounding quantity, etc., it can change suitably. However, in consideration of the balance between the varnish viscosity and the resin content of the prepreg and the influence on the appearance of the prepreg due to the increased viscosity of the varnish, the range of 50 to 80% by weight is preferable.

  The prepreg of the present invention is produced by impregnating a base material with the varnish of the resin composition of the present invention, drying at a temperature of, for example, 80 to 200 ° C., and curing to a B-stage. The production conditions of the prepreg, for example, the mixing method or the drying conditions are not particularly limited, but it is preferred that the solvent used in the varnish is volatilized by 80% by weight or more. Further, the drying time is determined in consideration of the gelation time of the varnish, and there is no particular time limit. The amount of varnish impregnated in the prepreg is preferably 35 to 70% by weight based on the total amount of the varnish solid and the base material.

  The substrate used for the prepreg of the present invention is not particularly limited as long as it is used when producing a metal foil-clad laminate or a multilayer printed wiring board. According to the present invention, a fiber substrate such as a woven fabric or a nonwoven fabric can be used as the substrate, and a sheet-like reinforcing substrate made of fibers is preferably used.

  The material of the fiber base material is inorganic fiber such as glass, alumina, asbestos, boron, silica alumina glass, silica glass, tyrano, silicon carbide, silicon nitride, zirconia; aramid, polyetheretherketone, polyetherimide, polyether Examples thereof include organic fibers such as sulfone, carbon, and cellulose; and mixed papers thereof. Glass fiber woven fabrics are preferably used. As the base material used for the prepreg, a glass cloth having a thickness of 20 to 200 μm is preferable.

  The manufacturing method of an insulating board, a laminated board, or a metal-clad laminated board is as follows. In the present invention, a prepreg or a laminate obtained by laminating a plurality of the prepregs is overlaid with a metal foil on one or both sides as necessary, for example, at a temperature in the range of 130 to 250 ° C, preferably 150 to 200 ° C. An insulating plate, a laminate or a metal-clad laminate can be produced by heat and pressure molding at a pressure in the range of 5 to 20 MPa, preferably 1 to 8 MPa. A metal-clad laminate can be formed using metal foil, and a circuit process can be applied to this to obtain a printed wiring board.

  As the metal foil used in the present invention, a copper foil or an aluminum foil is generally used, but a metal foil having a thickness of 5 to 200 μm which is usually used for a laminate can be used. Nickel, nickel-phosphorus, nickel-tin alloy, nickel-iron alloy, lead, lead-tin alloy, etc. are used as intermediate layers, and a 0.5-15 μm copper layer and a 10-300 μm copper layer are provided on both sides. Alternatively, a three-layer composite foil or a two-layer composite foil in which aluminum and copper foil are combined can be used.

  Using the metal-clad laminate in the present invention, a printed wiring board can be produced by subjecting a metal foil surface or a metal foil etched surface to circuit processing by a conventional method. In particular, these double-sided or single-sided wiring boards are used as inner layer boards, prepregs are arranged on both sides or one side, and after press molding, drilling with a drill for interlayer connection, plating, etc. is performed, and circuit processing etc. is performed in the same manner as above. A multilayer printed wiring board can be manufactured by applying.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples without departing from the technical idea of the present invention.

Example 1
In a glass flask equipped with a stirrer, condenser and thermometer, bisphenol A novolac type epoxy resin [epoxy equivalent: 210, manufactured by Japan Epoxy Resin Co., Ltd., 20% solvent (methyl ethyl ketone [hereinafter referred to as “MEK”]), 157S70B80] 50 parts by weight, melamine-modified phenol resin containing cresol skeleton [hydroxyl equivalent: 184, nitrogen content: 24.0%, Dainippon Ink & Chemicals, Inc., 50% solvent (MEK, propylene glycol monomethyl ether), phenolite EXB9831] 60 parts by weight, PPE (number average molecular weight 2140, weight average molecular weight 2830, manufactured by Asahi Kasei Corporation), 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa- as a phosphorus flame retardant 10-phosphaphenanthre 35 parts by weight of -10-oxide (hereinafter referred to as “HCA-HQ”, manufactured by Sanko Chemical Co., Ltd., phosphorus content: 9.5% by weight) is dissolved in 50 parts by weight of toluene and diluted for 1 hour at room temperature. Then, MEK was added while adjusting to a resin composition varnish having a solid content of 60% by weight. Here, the nitrogen content was 5.3 wt%, the PPE was 22.2 wt%, and the phosphorus content was 2.5 wt% with respect to the total solid content of the resin composition. These values were calculated as follows. The nitrogen content is calculated by adding the solid weight of the epoxy resin excluding the solvent weight of 20% for the epoxy resin, the solid weight of the phenol resin excluding the solvent weight of 50% for the phenol resin, the PPE weight, and the total weight of the phosphorus flame retardant. The ratio of the weight of the phenol resin solid content relative to the total solid content of the resin composition, that is, the weight percent of the phenol resin was calculated, and the amount of nitrogen contained in the phenol resin (24% in Example 1) was added thereto. Calculation of the amount of PPE calculated the ratio of the weight of PPE with respect to the total solid content of a resin composition. The phosphorus content was calculated by calculating the ratio of the phosphorus flame retardant to the total solid content of the resin composition and integrating the phosphorus content of the phosphorus flame retardant (9.5% in Example 1).
The obtained varnish was impregnated into a glass cloth (style 2116, E glass) having a thickness of about 100 μm and dried at 150 ° C. for 5 minutes to obtain a prepreg having a resin content of 50% by weight. The moldability, flame retardancy, and dielectric constant of the prepreg were tested.
Four obtained prepregs were stacked, 18 μm copper foils were stacked on both sides, and pressed under 4.0 Mpa, 180 ° C., 60 minutes pressing conditions to create a copper clad laminate. The produced copper clad laminate had a dielectric constant of 3.69 and a dielectric loss tangent of 0.0087.

Formability test The appearance of the obtained prepreg was observed to confirm the presence or absence of blurring, streaks, and smears.
Here, the presence of fading means a state in which the resin layer at the end of the base material at the time of pressure molding is too much of the resin impregnated in the prepreg, and the resin layer becomes thin or missing It is.
With streaks or smears, the varnish viscosity at the time of coating is non-uniform, etc., so that a high part of the resin is generated linearly or locally, streaks on the coated substrate, Alternatively, it is a state in which spotted unevenness (paint spots) occurs.

Flame Retardancy Test A test piece cut out to a length of 127 mm and a width of 12.7 mm was prepared from an evaluation substrate obtained by removing a copper foil by immersing a copper clad laminate in a copper etching solution, and a UL94 test method (Method V) ).

Dielectric property evaluation method (dielectric constant and dielectric loss tangent)
The obtained copper-clad laminate was immersed in a copper etching solution to obtain an evaluation substrate from which the copper foil was removed.
Using a dielectric constant measuring apparatus (product name: HP4291B) manufactured by Hewllet Packerd, the dielectric constant and dielectric loss tangent of the obtained resin plate and copper-clad laminate evaluation substrate at a frequency of 1 GHz were measured.

Example 2
In a glass flask equipped with a stirrer, a condenser and a thermometer, 90 parts by weight of a bisphenol A novolac type epoxy resin (epoxy equivalent: 210, manufactured by Japan Epoxy Resin Co., Ltd., 20% MEK, 157S70B80), cresol skeleton-containing melamine-modified phenol resin [Hydroxyl equivalent: 184, nitrogen content: 24.0%, Dainippon Ink & Chemicals, Inc., 50% solvent (MEK, propylene glycol monomethyl ether), phenolite EXB9831], 50 parts by weight, PPE (number average molecular weight 2140, Weight average molecular weight 2830, manufactured by Asahi Kasei Co., Ltd.) 5 parts by weight, as phosphorus flame retardant, 10 parts by weight of condensed acid phosphate ester PX-200 (manufactured by Daihachi Chemical Co., Ltd., phosphorus content 9.1% by weight) and HCA-HQ30 Part by weight dissolved in 10 parts by weight of toluene Thereby, stirring is carried out for 1 hour at room temperature, it was adjusted with MEK to a solid content of 60% by weight of the resin composition varnish. Here, the nitrogen content was 4.2 wt%, the PPE was 3.5 wt%, and the phosphorus content was 2.6 wt% with respect to the total solid content of the resin composition.
The obtained varnish was impregnated into a glass cloth (style 2116, E glass) having a thickness of about 100 μm and then dried at 150 ° C. for 5 minutes to obtain a prepreg having a resin content of 50% by weight.
Four obtained prepregs were stacked, 18 μm copper foils were stacked on both sides, and a copper clad laminate was prepared under the pressing conditions of 180 ° C., 60 minutes, 4.0 MPa. The laminate properties (including the prepreg moldability) were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The produced copper clad laminate had a dielectric constant of 3.75 and a dielectric loss tangent of 0.0089.

Example 3
A prepreg and a copper clad laminate were prepared in the same manner as in Example 2 except that 50 parts by weight of silica was added.
The obtained varnish had a nitrogen content of 4.2% by weight, a PPE of 3.5% by weight, and a phosphorus content of 2.6% by weight with respect to the total solid content of the resin composition excluding silica as a filler. %, And the amount of filler added was 35% by weight with respect to the total solid content of the resin composition (excluding the filler).
The laminate properties (including the prepreg moldability) were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The obtained copper-clad laminate had a dielectric constant of 3.90 and a dielectric loss tangent of 0.0076.

Example 4
In a glass flask equipped with a stirrer, condenser and thermometer, bisphenol A novolak type epoxy resin (epoxy equivalent: 210, made by Japan Epoxy Resin Co., Ltd., MEK 20% contained, 157S70B80) 55 parts by weight, cresol skeleton containing melamine modified phenolic resin [Hydroxyl equivalent: 151, nitrogen content: 18.0%, Dainippon Ink & Chemicals, Inc., 50% solvent (MEK, propylene glycol monomethyl ether), phenolite EXB9848], 50 parts by weight of terminal epoxidized PPE (number average) Molecular weight 3200, weight average molecular weight 5000, epoxy equivalent 1130, manufactured by Asahi Kasei Co., Ltd.) 30 parts by weight, as a phosphoric flame retardant, condensed acid phosphate ester PX-200 (manufactured by Daihachi Chemical Co., phosphorus content 9.1% by weight) 10 parts by weight and HCA-HQ35 The amount unit, dissolved diluted 50 parts by weight of toluene, stirring is carried out for 1 hour at room temperature, was adjusted with MEK to a solid content of 60% by weight of the resin composition varnish. Here, the nitrogen content was 3.4 wt%, the terminal epoxidized PPE was 22.4 wt%, and the phosphorus content was 2.5 wt% with respect to the total solid content of the resin composition.
Hereinafter, a prepreg and a copper clad laminate were prepared in the same manner as in Example 1.
The laminate properties (including the prepreg moldability) were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The produced copper clad laminate had a dielectric constant of 3.64 and a dielectric loss tangent of 0.0085.

Example 5
In a glass flask equipped with a stirrer, condenser and thermometer, 90 parts by weight of a bisphenol A novolac type epoxy resin (epoxy equivalent: 210, manufactured by Japan Epoxy Resin Co., Ltd., 20% MEK, 157S70B80), melamine-modified phenol resin [cresol skeleton Hydroxyl group equivalent: 146, nitrogen content: 19.0%, Dainippon Ink & Chemicals, Inc., MEK 40% contained, Phenolite LA 1356], 50 parts by weight, PPE (number average molecular weight 2140, weight average molecular weight 2830, Asahi Kasei Co., Ltd.) 6 parts by weight, as a phosphorus flame retardant, 45 parts by weight of HCA-HQ is dissolved and diluted in 50 parts by weight of toluene, stirred for 1 hour at room temperature, and a resin composition varnish having a solid content of 60% by weight. It adjusted with MEK so that it might become. Here, the nitrogen content was 3.2% by weight, the PPE was 4.1% by weight, and the phosphorus content was 2.8% by weight with respect to the total solid content of the resin composition.
Hereinafter, a prepreg and a copper clad laminate were prepared in the same manner as in Example 1.
The laminate properties (including the prepreg moldability) were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The produced copper clad laminate had a dielectric constant of 3.88 and a dielectric loss tangent of 0.0075.

Comparative Example 1
The cresol skeleton-containing melamine-modified phenol resin of Example 1 was used as a melamine-modified phenol resin (hydroxyl equivalent: 127, nitrogen content: 13.0%, Dainippon Ink & Chemicals, Inc., MEK 40% contained, Phenolite LA-7054). A prepreg and a copper clad laminate were produced in the same manner as in Example 1 except that.
The obtained varnish had a nitrogen content of 2.9% by weight, a PPE of 22.2% by weight, and a phosphorus content of 2.4% by weight based on the total solid content of the resin composition.
The laminate properties (including the prepreg moldability) were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The produced copper clad laminate had a dielectric constant of 3.60 and a dielectric loss tangent of 0.0080.

Comparative Example 2
A prepreg and a copper-clad laminate were produced in the same manner as in Example 1 except that PPE having a number average molecular weight of 19400 and a weight average molecular weight of 40000 was used as the PPE of Example 1.
The obtained varnish had a nitrogen content of 5.3% by weight, a PPE of 22.2% by weight, and a phosphorus content of 2.5% by weight with respect to the total solid content of the resin composition.
The laminate properties (including the prepreg moldability) were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The produced copper clad laminate had a dielectric constant of 3.56 and a dielectric loss tangent of 0.0077.

Comparative Example 3
A prepreg and a copper clad laminate were produced in the same manner as in Example 1 except that 25 parts by weight of HCA-HQ of Example 1 was added.
The obtained varnish had a nitrogen content of 5.8% by weight, a PPE of 24.0% by weight, and a phosphorus content of 1.9% by weight based on the total solid content of the resin composition.
The laminate properties (including the prepreg moldability) were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The produced copper clad laminate had a dielectric constant of 3.61 and a dielectric loss tangent of 0.0082.

Comparative Example 4
A prepreg and a copper clad laminate were produced in the same manner as in Example 3, except that 70 parts of the silica of Example 3 was added.
The obtained varnish had a nitrogen content of 4.2% by weight, a PPE of 17.6% by weight, and a phosphorus content of 2.6% by weight with respect to the total solid content of the resin composition excluding silica as a filler. The amount of filler added was 49.3% by weight based on the total solid content of the resin composition.
The laminate properties (including the prepreg moldability) were evaluated in the same manner as in Example 1, and the results are shown in Table 1. The produced copper clad laminate had a dielectric constant of 3.94 and a dielectric loss tangent of 0.0074.

The laminates in the examples of the present invention are excellent in flame resistance and dielectric properties, and the prepreg used at this time is excellent in appearance and has a good balance of properties of flame resistance, dielectric constant and moldability in the laminates. found.
On the other hand, in Comparative Example 1 using melamine-modified phenol having a nitrogen content equal to or less than the preferred range of the present invention, the moldability and dielectric constant are good, but the flame retardancy is V-1.
Further, Comparative Example 2 in which the molecular weight of PPE is not less than the range of the present invention is good in flame retardancy, but has moldability, particularly streaks and smears, and has a low dielectric constant. Due to the occurrence of streaks and smears, the plate thickness accuracy of the entire substrate was lowered, and the surface smoothness of the laminate was lowered. In addition, since the resin content is not uniform, the dielectric characteristics become unstable.
In Comparative Example 3 in which the phosphorus content is not more than the preferred range of the present invention, the moldability and the dielectric constant are good, but the flame retardancy is V-1.
In Comparative Example 4 in which the inorganic filler that can be optionally added in the present invention is more than the preferred range of the present invention, flame retardancy and dielectric constant are good, but moldability, particularly blurring and smearing occurred. Since fading occurred, the plate thickness was thinner than a predetermined thickness, and the dielectric properties were lowered due to the resin content being lowered.

  Although the resin composition of the present invention is non-halogen, it has excellent flame retardancy, is excellent in dielectric properties such as dielectric constant and dielectric loss tangent, and is excellent in moldability. In addition to being excellent in flame retardancy and dielectric properties, the prepreg of the resin composition of the present invention has a good appearance. Furthermore, a metal-clad laminate using the resin composition of the present invention and a printed wiring board using the same are excellent in the balance of flame retardancy, dielectric properties and moldability.

Claims (8)

(A) a non-halogenated epoxy group-containing compound having at least two epoxy groups in one molecule;
(B) a resin curing agent that is a melamine- modified phenol resin curing agent and has a hydroxyl group equivalent of 140 to 190 and a nitrogen content of 17.0 wt % to 25.0 wt %;
(C) a polyphenylene ether having a number average molecular weight (Mn) of 1500 to 3500 and a weight average molecular weight (Mw) of 2500 to 7000 or a modified polyphenylene ether having a terminal epoxidized ;
(D) An amount that is a phosphorus-containing flame retardant and that the phosphorus content is 2.0 to 10.0% by weight with respect to the total solid content of the components (A), (B), (C), and (D) A phosphorus-containing flame retardant formulated in
(E) An inorganic filler is not included, but when it is included, the inorganic content is in the range of 4 to 40% by weight with respect to the total solid content of the components (A), (B), (C) and (D). A filler,
A flame retardant resin composition comprising:   (C) The flame-retardant resin composition of Claim 1 whose number average molecular weights (Mn) of polyphenylene ether are 1900-2300 and whose weight average molecular weights (Mw) are 2500-3000. The flame retardant resin composition according to claim 1 or 2 , wherein the (B) resin curing agent further contains a cresol [C ₆ H ₄ (CH ₃ ) OH] skeleton . The terminal epoxidized polyphenylene ether has a number average molecular weight (Mn) of 1500 to 3500, a weight average molecular weight (Mw) of 4500 to 7000, and an epoxy equivalent of 800 to 1200 . The flame retardant resin composition according to Item 1 . Flame retardancy containing 4 to 40% by weight of inorganic filler with respect to the total solid content of components (A), (B), (C) and (D) according to any one of claims 1 to 4. Resin composition.   The prepreg using the flame-retardant resin composition of any one of Claims 1-5.   A metal-clad laminate using the flame retardant resin composition according to any one of claims 1 to 5 or the prepreg according to claim 6.   The printed wiring board using the flame-retardant resin composition of any one of Claims 1-5, or the prepreg of Claim 6.