JP2006063230A - Thermosetting resin composition, and prepreg, metal foil and substrate using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-performance thermosetting resin composition excellent in low-cost nature, processability and reliability, wherein the thermosetting resin composition has dielectric properties such as a low dielectric constant and a low dielectric loss suitable for high-frequency applications; when the resin composition is applied to a prepreg or metal foil, the amount of the resin composition can easily be controlled; and dimensional stability can be improved by making it possible to control flow during pressing, and to provide a prepreg, metal foil and a substrate using the same. <P>SOLUTION: The thermosetting resin composition comprises a thermosetting resin composition containing a vinylbenzyl compound as an essential ingredient and 1-30 wt% based on the total resin volume of a thermoplastic resin having a dielectric constant (ε') of 3.0 or less and a dielectric loss tangent (tan δ) of 0.002 or less in the 5 GHz frequency band. There are also provided a prepreg, metal foil and a substrate using the thermosetting resin composition. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a thermosetting resin composition, a prepreg using the same, a metal foil and a substrate, and more particularly, an electronic component having a low relative dielectric constant and a low dielectric loss that is suitable for use in a high frequency (gigahertz) band. The present invention relates to a thermosetting resin composition used for a substrate for use, a prepreg using the same, a metal foil, and a substrate.

  In recent years, with the increase in capacity and speed of communication devices, there has been a demand for substrate materials used for electronic components constituting the communication devices to cope with downsizing, high density, and high speed. Specifically, a material having a low dielectric constant and a low dielectric loss that can be used in the gigahertz band is desired.

  Conventionally, in a printed wiring board, an epoxy resin has been generally used as a material for a copper-clad laminate. However, a substrate using an epoxy resin is inexpensive and excellent in workability and plating properties, but has a drawback of poor dielectric properties in a high frequency band and cannot meet the above requirements. It has also been proposed to use a fluororesin as a substrate material, but the fluororesin is excellent in dielectric properties, but inferior in workability and adhesiveness, and is very expensive, so its use is limited to special applications. This is the current situation.

  Currently, polyphenylene ether and BT (bismaleimide / triazine) resin are used as materials that can cope with these problems. However, since these materials have a relative dielectric constant (ε ′) and dielectric loss tangent (tan δ) that are considerably larger than those of fluororesin, and BT resin has high hygroscopicity and poor workability, the gigahertz band, particularly 5 GHz or more. In this frequency band, the dielectric characteristics were insufficient.

Therefore, as a material having a dielectric property superior to that of polyphenylene ether or BT resin, Patent Literature 1 and the like mix a thermoplastic resin of an alicyclic olefin polymer with a thermosetting resin, specifically, an epoxy group-containing compound. Resin compositions have been reported. Similarly, as a material excellent in dielectric properties, Patent Document 2 proposes a resin composition containing a compound having a styrene group as a crosslinking component and a thermoplastic resin. Furthermore, Patent Document 3 includes a vinylbenzyl compound as a thermosetting resin particularly suitable for high-frequency applications. Such a compound has excellent mechanical strength, no volatility, and excellent dielectric properties. It has been reported.
JP 2003-22711 A (Claims etc.) JP 2003-12710 A (Claims etc.) JP 2001-181460 A (Claims etc.)

  However, the resin composition for high frequency (gigahertz) band, which has been reported so far as a resin to replace polyphenylene ether and BT resin, is not always satisfactory, and all have a point to be improved.

  For example, when a thermoplastic resin is used as a main component as in the resin composition described in Patent Document 1, it exhibits excellent performance in dielectric properties, but is insufficient in terms of solvent resistance and strength. On the other hand, when the thermosetting resin is a main component, there is a problem that the dielectric characteristics are greatly impaired.

  Such a problem is improved by using the resin composition listed in Patent Document 2, but when a compound having a styrene group is used as a crosslinking component as shown in Patent Document 2, the cured product When the prepreg is prepared using divinylbenzene because of its low strength, there is a problem that the amount of divinylbenzene in the prepreg is not stable because the boiling point of divinylbenzene is low.

  In addition, when a vinylbenzyl compound which is a thermosetting resin suitable for use in a high frequency (gigahertz) band, which is described in Patent Document 3, has the above-mentioned advantages, it has a viscosity when made into a solution. Therefore, there is a problem that the amount of resin is reduced when prepreg is formed. Further, when the resin concentration in the solution is increased in order to increase the viscosity, there is a problem that the reaction is accelerated and the lifetime is remarkably shortened. Further, since the dissolved resin itself has a low viscosity, there is a problem that when the prepreg is pressed, the resin flows out in a large amount, and it is difficult to control the thickness and dimensions.

  As described above, there has been no substrate material so far that exhibits particularly excellent dielectric properties in the high-frequency band and that also has good performance in terms of workability, reliability, cost, etc. It is.

  Accordingly, an object of the present invention is a thermosetting resin composition having a low dielectric constant and low dielectric loss suitable for high frequency applications, and when the resin composition is applied to a prepreg or a metal foil, The amount of the resin composition is easy to control, and flow control is possible at the time of pressing, so that dimensional accuracy can be improved. Low cost, high workability and high reliability. The object is to provide a thermosetting resin composition, a prepreg, a metal foil and a substrate using the same.

  In order to solve the above-mentioned problems, the present inventors have intensively studied paying attention to a vinylbenzyl compound as a thermosetting resin, and as a result, by adding a predetermined thermoplastic resin to the vinylbenzyl compound, The inventors have found that a resin composition that can achieve the object can be obtained, and have completed the present invention.

  That is, the thermosetting resin composition of the present invention is a thermosetting resin composition containing a vinylbenzyl compound as a main component and has a relative dielectric constant (ε ′) of 3.0 or less in a frequency band of 5 GHz, and A thermoplastic resin having a dielectric loss tangent (tan δ) of 0.002 or less is contained in an amount of 1 to 30% by weight based on the total resin amount.

  The prepreg of the present invention is characterized in that the thermosetting resin composition of the present invention is impregnated into a glass cloth, and the proportion of the glass component is 5 to 60% by weight. .

  Furthermore, the metal foil with resin of the present invention is characterized in that the thermosetting resin composition of the present invention is applied.

  Furthermore, the substrate of the present invention is characterized in that the prepreg of the present invention and a metal foil or the metal foil with a resin of the present invention is laminated.

  According to the present invention, it is possible to obtain a thermosetting resin composition having a dielectric property with a low relative dielectric constant and a low dielectric loss suitable for high frequency applications. In addition, when this resin composition is applied to a prepreg, it is easy to control the amount of the resin composition, and flow control is possible when pressing the prepreg to improve dimensional accuracy. Can do. Furthermore, even when this resin composition is applied to a metal foil, a multilayer substrate having excellent dimensional accuracy can be provided because the resin fluidity during pressing is suppressed as in the case of the prepreg. As a result, this thermosetting resin composition has an effect of being excellent in workability and reliability in addition to low cost. In addition, in the present invention, by using such a high-performance thermosetting resin composition, it is possible to provide electronic components such as a prepreg, a metal foil, and a circuit board that are excellent in reliability suitable for use in a high frequency band. it can.

Hereinafter, embodiments of the present invention will be described in detail.
The thermosetting resin composition of the present invention contains a predetermined amount of a specific thermoplastic resin with respect to the thermosetting resin composition containing a vinylbenzyl compound monomer or prepolymer as a main component. As a thermosetting resin, vinylbenzyl compounds are extremely excellent in dielectric properties in the high frequency band, have a high glass transition point of around 180 ° C, do not volatilize until curing, and do not cause compositional deviation. On the other hand, when it is made into a solution, the viscosity is low, and when it is made into a prepreg, the resin flows out, and it is difficult to control the thickness and dimensions. Therefore, in the present invention, the handling is improved without impairing the original characteristics of the vinylbenzyl compound by blending a predetermined amount of the specific thermoplastic resin together with the vinylbenzyl compound as the main component.

（式中、Ｒ¹は炭素数２〜２０の２価の有機基を示し、Ｒ²は同一であっても異なっていてもよく、ハロゲン原子または炭素数１〜５のアルキル基、アルコキシ基、チオアルコキシ基若しくはアリール基を示し、ｘは０〜４の整数を示し、ｍは０〜２０の整数を示す）で示されるビニルベンジル化合物を好適に用いることができる。 As the vinylbenzyl compound, the following general formula (1),

(In the formula, R ¹ represents a divalent organic group having 2 to 20 carbon atoms, R ² may be the same or different, and is a halogen atom or an alkyl group having 1 to 5 carbon atoms, an alkoxy group, A vinylbenzyl compound represented by thioalkoxy group or aryl group, x represents an integer of 0 to 4, and m represents an integer of 0 to 20) can be preferably used.

  In the vinylbenzyl compound represented by the general formula (1), one or more fluorene compounds, a vinylbenzyl halide, and optionally a dihalomethyl compound having 1 to 20 carbon atoms are reacted in the presence of an alkali. Can be obtained. In the fluorene compound used in the present invention, fluorene and its aromatic ring moiety may be substituted with an alkyl group, an alkoxy group, a thioalkoxy group, or an aryl group. These may be used alone or in admixture of two or more as required.

  Examples of the vinyl benzyl halide used in the present invention include m-vinyl benzyl chloride, p-vinyl benzyl chloride, m-vinyl benzyl bromide, p-vinyl benzyl bromide and the like. These may be used alone or in admixture of two or more, and it is particularly preferable to use m-vinylbenzyl chloride and p-vinylbenzyl chloride.

Furthermore, the dihalomethyl compound used in the present invention is CH ₂ X ₂ or a compound having two or more —CH ₂ X groups (where X represents a halogen atom) in the molecule, and has 2 to 20 carbon atoms. Preferably there is. Specific examples of compounds include alkyl halides such as 1,2-dichloroethane and 1,4-dichloroheptane, o-xylylene dichloride, 4,4'-bis (chloromethyl) biphenyl, 1,4-bis (Chloromethyl) naphthalene and the like can be mentioned. These may be used alone or in admixture of two or more as long as no intramolecular cyclization reaction occurs.

  The equivalent ratio of vinylbenzyl halide to the halomethyl group of the dihalomethyl compound can be selected particularly within the range where gelation by the dihalomethyl compound does not occur, and the vinylbenzyl halide / dihalomethyl compound ratio is 1.0 / 0 to 0.1. A range of /0.9 is preferred. If the vinyl benzyl halide is less than this range, the curability is lowered and the physical properties of the cured product are greatly lowered.

  Use dimethylformamide, dimethyl sulfoxide, dimethylacetamide, N-methylpyrrolidone, dioxane, acetonitrile, tetrahydrofuran, ethylene glycol dimethyl ether, 1,3-dimethoxypropane, tetramethylene sulfone, methyl ethyl ketone, acetone, cyclohexanone, etc. as the reaction solvent. Is preferred. These may be used alone or in combination of two or more, and are appropriately selected according to the raw materials and reaction conditions.

  The alkali used in the present invention is an alkali metal or alkaline earth metal alkoxide, hydride, or hydroxide. Specific examples thereof include sodium ethoxide, sodium hydride, sodium borohydride, potassium hydroxide, water. Sodium oxide etc. are mentioned.

  The vinylbenzyl compound used in the present invention is a phase transfer catalyst such as a quaternary ammonium salt, and the fluorene compound, vinylbenzyl halide, and dihalomethyl compound are mixed in a water / organic solvent mixture in the presence of an alkali. It can obtain by making it react.

  The vinyl benzyl compound according to the present invention can be used by mixing two or more kinds from the viewpoint of workability and the like, and is appropriately selected within a range that does not impair dielectric properties.

  The thermoplastic resin blended in the thermosetting resin composition containing the vinylbenzyl compound as a main component has a relative dielectric constant (ε ′) of 3.0 or less and a dielectric loss tangent (tan δ) of 0 in a frequency band of 5 GHz. Although it should just be 0.002 or less and should not be restrict | limited especially, Preferably, a polystyrene, polyphenylene ether (PPE), polybenzocyclobutene, a petroleum resin etc. can be mentioned. Of these, polyphenylene ether is particularly preferable from the viewpoint of mechanical strength, particularly thermal shock resistance.

  Such polyphenylene ether is a general term for polymers having a skeleton having a structural unit represented by the following general formula (2). It may be a homopolymer consisting of only one of these structural units or a copolymer in which two or more are combined.

（式中、Ｒ³〜Ｒ⁶は互いに同一でも異なっていてもよく、水素原子または低級アルキル基を表す）

(In formula, R < ³ > -R < ⁶ > may mutually be same or different, and represents a hydrogen atom or a lower alkyl group.)

  The molecular weight of the thermoplastic resin used in the present invention is preferably 10,000 to 100,000 in terms of weight average molecular weight. When the weight average molecular weight is less than 10,000, there is a problem that the strength of the cured product is lowered. On the other hand, when it exceeds 100,000, there is a problem that the thermoplastic resin is easily separated after curing or in a solution.

  Moreover, this thermoplastic resin is mix | blended with the ratio of 1-30 weight% with respect to the total resin amount to the thermosetting resin composition which has a vinylbenzyl type compound as a main component, Preferably it is 1-10 weight%. If the blending ratio of the thermoplastic resin is less than 1% by weight, the effect of suppressing the flow of the resin when it is prepreg is small, and the thickness and dimensions cannot be easily controlled, whereas it exceeds 30% by weight. And the properties of the thermoplastic resin become too strong, and the decrease in solvent resistance and heat resistance becomes remarkable.

  In addition, it is preferable to mix | blend a polymerization inhibitor with the thermosetting resin composition of this invention in the range which does not impair a dielectric property, and this can lengthen the pot life of a resin material. As the polymerization inhibitor, a known substance can be used as a substance that rapidly reacts with a radical formed from a polymerization initiator or monomer to disappear and stabilize radical species, and stops the polymerization reaction, and should be particularly limited. Although it is not a thing, Preferably it is 2,4-dinitrophenol, a phenothiazine, etc. other than hydroquinone, especially tetramethylhydroquinone. The addition amount of the polymerization inhibitor is not particularly limited, but is generally 0.01 to 1% by weight based on the total resin amount.

  Furthermore, a flame retardant, a plasticizer, an anti-degradation agent, etc. can be added to the thermosetting resin composition of the present invention as long as the purpose of the present invention is not impaired.

  Next, the prepreg of the present invention is obtained by impregnating a glass cloth with the thermosetting resin composition. When impregnating a glass cloth with a thermosetting resin composition, a monomer or prepolymer of a vinylbenzyl compound, the thermoplastic resin, and a polymerization inhibitor, if necessary, a nonpolar material such as toluene or xylene. Used as a solution dissolved in an organic solvent. In this case, preparation is performed so that the ratio of the thermosetting resin component and the additive in the solution is 40 to 70% by weight in total. A solution of this thermosetting resin composition is generally impregnated into a glass cloth or the like to form a prepreg, and then laminated with a metal foil or the like to form a substrate. If the solution concentration is less than 40% by weight, Dielectric properties may be lowered due to the small amount of resin components contained, while on the other hand, when the solution concentration exceeds 70% by weight, the solubility in the solvent becomes very poor, and the thickness variation of the prepreg and the pressed product is reduced. It gets bigger.

  Further, the material of the glass cloth used for the prepreg is not particularly limited, and those usually used in a printed circuit board can be used. For example, the number per unit length of warp and weft, the thickness and the unit area The thing whose weight corresponds to Japanese Industrial Standard R-3414 or the American military standard (MIL standard) is mentioned. Moreover, the glass cloth of the range which does not correspond to these specifications may be used, and the mixed textiles of glass fibers and fibers other than glass fibers, such as a carbon fiber or a ceramic fiber, may be sufficient. As this glass fiber, E glass (relative dielectric constant ε ′ = 7, dielectric loss tangent tan δ = 0.003, 1 GHz), D glass (ε = 4, tan δ = 0.0013, 1 GHz), H glass (ε = 11) Tan δ = 0.003, 1 GHz), C glass, S glass, NE glass, and other glass component compositions. From the viewpoint of balance between cost and dielectric properties, E glass is preferably used.

  The thickness of the glass cloth is not particularly limited, and those having a thickness of 10 to 300 [mu] m, particularly about 50 to 200 [mu] m, and further 50, 100, 150, and 180 [mu] m can be used as needed.

  Further, the glass cloth needs to be surface-treated in advance in order to improve the adhesion between the resin impregnated in the yarn bundle and the glass fiber. Examples of the surface treatment agent used for the surface treatment include silane coupling agents such as aminosilane compounds, vinylsilane compounds, styrene silane compounds, and methacrylsilane compounds. Of these, methacryl silane and vinyl silane are particularly suitable in combination with vinyl benzyl compounds. Preferred examples of the methacrylic silane compound include γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, and the like.

  As the surface treatment method of the glass cloth by the coupling agent used in the surface treatment of the glass cloth, the kind and the blending conditions, and the coupling agent can be performed by a known method. As a treatment method, a general dipping method or spraying method can be used. A dipping method using ultrasonic waves (JP-A 63-165441) or a dipping method using a roller jet dehydrator (JP Sho 63-175165) can also be used.

  Moreover, the ratio for which the glass component accounts in the prepreg of this invention is 5 to 60 weight%, Preferably it is 20 to 60 weight%. If this ratio is less than 5% by weight, the dimensional stability and strength after curing of the prepreg are insufficient, while if it exceeds 60% by weight, the dielectric properties are inferior, which is not preferable.

  Next, the board | substrate of this invention is formed by laminating | stacking the said prepreg and metal foil, and is formed as a laminated board with a hot press.

  The metal foil used for the substrate is not particularly limited as long as a suitable metal foil is selected from metals having good conductivity such as gold, silver, copper, and aluminum. Among these, a copper foil is preferably used from the viewpoints of cost and grade. The metal foil may be produced by either electrolytic method or rolling method. However, if foil peel strength is desired, electrolytic foil should be used. A rolled foil with little influence can be used. It is preferable that at least the surface in contact with the prepreg is subjected to a surface treatment. As a surface treatment for the metal foil, in addition to a roughening treatment for forming irregularities, an alloy layer as exemplified in Japanese Patent No. 3295308 may be formed on the surface of the metal foil. The thickness of the metal foil is preferably 8 to 70 μm, and more preferably 12 to 35 μm.

About molding and thermosetting when forming a substrate by laminating prepreg and metal foil, temperature is 100 to 250 ° C., pressure is 9.8 × 10 ^{5 to} 7.84 × 10 ⁶ Pa (10 to 80 kg / cm ² ). It is preferable to carry out within the range of 0.5-20 hr on condition of this. The substrate may be molded in a plurality of stages within the above range.

  The substrate of the present invention thus obtained has excellent dielectric properties in the high frequency band and exhibits good adhesion to metal foils, particularly copper foils. By patterning such a substrate with metal foil and appropriately combining with a capacitor, coil, filter, etc., a high-performance electronic component for high frequency can be obtained.

  In addition, the resin-coated metal foil of the present invention is obtained by applying the thermosetting resin composition of the present invention. By sequentially laminating this on the core substrate to form a circuit, it can be used in a high frequency band. A multilayer substrate suitable for the above can be formed. In addition, as metal foil to be used, what was mentioned above can be used conveniently.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. The present invention is not limited to these examples.
Examples 1-5
A vinylbenzyl compound (hereinafter referred to as “VB resin”) represented by the general formula (1) (R ¹ = — (CH ₂ ) ₆ —, x = 0, m = 1) and a thermoplastic resin (PPE, Asahi Kasei) Industrial Co., Ltd., trade name: Zylon S201A, ε ′ = 2.7, tan δ = 0.014) and phenothiazine (reagent (polymerization inhibitor) manufactured by Kanto Chemical Co., Ltd.) are shown in Table 1 below. A thermosetting resin solution was prepared by dissolving in toluene at the ratio shown in FIG. These resin solutions were applied to a surface-treated glass cloth (E glass manufactured by Asahi Schavel Co., Ltd.) using a coating machine, and then dried at 110 ° C. for 1 hour to obtain a prepreg.

The VB resin was produced as follows.
In a flask equipped with a temperature controller, a stirrer, a cooling condenser, a dropping funnel and an oxygen blowing port, 207 g (0.5 mol) of 1,6-bis (9-fluorenyl) hexane, 400 g of toluene, tetra-n-butylammonium 142.5 g of bromide, vinylbenzyl chloride (manufactured by Seimi Chemical Co., Ltd., trade name: CMS-AM, m / p isomer: 50/50 wt% mixture) 152.5 g (purity 91%, 1.0 mol) and phenothiazine 0 .3 g was added and the temperature was raised to 40 ° C. with stirring to obtain a uniform solution. To this, 80 g of 50 wt% NaOH aqueous solution (NaOH, 1 mol) was added, and then reacted at 70 ° C. for 8 hours. Next, the flask contents were neutralized with 2N hydrochloric acid, washed twice with distilled water, toluene was distilled off under reduced pressure, and the resulting orange viscous liquid was vacuum dried to obtain a molecular weight Mw = 1500. A VB resin (GPC, in terms of polystyrene) was obtained.

  Next, 10 layers of this prepreg were laminated and step cured at 120 ° C., 150 ° C., and 180 ° C. for 1 hour using a vacuum hot press machine to obtain a laminated plate.

１）ポリスチレン、商品名：ダイヤレックスＨＦ−５５（三菱化学（株）製、ε’＝２．４、ｔａｎδ＝０．０００３）

1) Polystyrene, trade name: Dialex HF-55 (manufactured by Mitsubishi Chemical Corporation, ε ′ = 2.4, tan δ = 0.0003)

Comparative Examples 1-6
Divinylbenzene as a crosslinking component, the VB resin or triallyl isocyanate (TAIC) used in Example 1 and a thermoplastic resin were dissolved in toluene at the ratio shown in Table 2 below, and thermosetting was performed. A conductive resin solution was prepared. These resin solutions were applied to a surface-treated glass cloth (E glass manufactured by Asahi Schavel Co., Ltd.) using a coating machine, and then dried at 110 ° C. for 1 hour to obtain a prepreg.

  Next, 10 layers of this prepreg were laminated and step cured at 120 ° C., 150 ° C., and 180 ° C. for 1 hour using a vacuum hot press machine to obtain a laminated plate.

２）ポリメチルメタクリレート、商品名：スミペックスＬＧ６（ε’＝２．９、ｔａｎδ＝０．０３３）

2) Polymethylmethacrylate, trade name: Sumipex LG6 (ε ′ = 2.9, tan δ = 0.033)

The following evaluation was performed with respect to the laminates obtained in Examples 1 to 5 and Comparative Examples 1 to 6.
(1) Dielectric constant and dielectric loss tangent The test laminate was cut into a width of 1.2 mm and a length of 100 mm, and this was used as a measurement sample. The measurement was performed at 5 GHz using a cavity resonator perturbation method.
(2) Solvent resistance The test laminate was cut into 10 mm x 50 mm and 1 mm thickness and used as a measurement sample. The measurement sample was allowed to stand at 25 ° C. and 60% RH for 24 hours or more, and then the weight was measured. Thereafter, the sample was immersed in toluene (ultrasonic 10 minutes). At this time, the case where there was no visual change and the weight change was 0.3% or less was marked with ◯, and the others were marked with x.

(3) Resin fluidity Separately, a prepreg having a glass cloth weight of 35 to 40% was used, and the change in weight before and after pressing was calculated according to the following formula.
Resin flow rate (%) = 100 × (weight before pressing−weight after pressing) / weight after pressing Here, the weight after pressing is the weight when the resin flowing after pressing is cut. In the same manner as described above, pressing was performed by laminating 10 layers of prepreg and performing step cure with a vacuum hot press at 120 ° C., 150 ° C., and 180 ° C. for 1 hour. The heating rate was 5 ° C./min, the pressure was 9.8 × 10 ⁵ Pa (10 kg / cm ² ), and the holding time for each step was 1 hour. A resin flow rate according to the above formula was 15% or less. These evaluation results are shown in Table 3 below.

３）ＶＢ樹脂とポリフェニレンエーテルが分離したため、基板を作製することができなかった。

3) Since the VB resin and polyphenylene ether were separated, the substrate could not be produced.

  From Table 3 above, it can be seen that the laminate using the thermosetting resin composition of the present invention exhibits excellent dielectric properties and solvent resistance after curing. Moreover, it turns out that the resin fluidity | liquidity in high temperature is also improved. As a result, the thermosetting resin composition of the present invention can easily provide dimensional control, and can provide an electronic component such as a circuit board excellent in reliability suitable for use in a high frequency band.

  In order to confirm the effect of the polymerization inhibitor, a 60 wt% toluene solution of the resin composition of Example 1 and a 60 wt% toluene solution of a resin composition prepared in the same manner except that it does not contain phenothiazine; Each was stored sealed in a dark place at 25 ° C. for 30 days, and then the state change of the solution was confirmed. As a result, it was confirmed that those containing phenothiazine did not change, whereas those containing phenothiazine were gelled.

Example 6 and Comparative Example 7
In order to confirm the resin fluidity of the metal foil with resin, the thermosetting resin solution of Example 2 was used as Example 6, the thermosetting resin solution of Comparative Example 3 was used as Comparative Example 7, and the metal with resin was used. Each foil was made. As the metal foil, a copper foil (manufactured by Nikko Materials) having a thickness of 0.018 mm was used. Moreover, it coated so that a resin layer might be formed on copper foil so that 70 micrometers might be formed, and the copper foil with resin was produced by making it dry in a 110 degreeC dryer furnace for 1 hour.

The obtained copper foil with resin was cut into 100 mm × 100 mm, sandwiched between fluororesin release films having a smooth surface, and further placed between SUS plates. Next, the pressure was set to 1.96 × 10 ⁶ Pa (20 kg / cm ² ), the temperature was raised to 120 ° C. at 5 ° C./min, and then held for 1 hour. The resin flow was calculated according to the following formula.
Resin flow rate (%) = 100 × (area after pressing−area before pressing) / area before pressing The area before pressing is 100 cm ² .

As a result of the calculation, Example 6 was 15% and Comparative Example 7 was 37%. If the resin flow rate is 20% or less, there is no practical problem, and it can be seen that the resin-attached metal foil of the present invention also has good resin fluidity at high temperatures.

Claims (10)

  Heat having a relative permittivity (ε ′) of 3.0 or less and a dielectric loss tangent (tan δ) of 0.002 or less in a thermosetting resin composition containing a vinylbenzyl compound as a main component in a frequency band of 5 GHz. A thermosetting resin composition comprising 1 to 30% by weight of a plastic resin based on the total resin amount.   The thermosetting resin composition according to claim 1, wherein the thermoplastic resin is polyphenylene ether.   The thermosetting resin composition according to claim 1 or 2, wherein the thermoplastic resin has a weight average molecular weight of 10,000 to 100,000. The vinylbenzyl compound is represented by the following general formula (1),

(In the formula, R ¹ represents a divalent organic group having 2 to 20 carbon atoms, R ² may be the same or different, and is a halogen atom or an alkyl group having 1 to 5 carbon atoms, an alkoxy group, A thioalkoxy group or an aryl group, wherein x represents an integer of 0 to 4 and m represents an integer of 0 to 20). Thermosetting resin composition.   The thermosetting resin composition according to any one of claims 1 to 4, wherein a polymerization inhibitor is added.   The thermosetting resin composition according to claim 5, wherein the polymerization inhibitor is at least one selected from the group consisting of tetramethylhydroquinone, 2,4-dinitrophenol, and phenothiazine.   A prepreg, wherein the thermosetting resin composition according to any one of claims 1 to 6 is impregnated into a glass cloth, and the proportion of the glass component is 5 to 60% by weight.   A substrate comprising the prepreg according to claim 7 and a metal foil laminated.   A metal foil with resin, wherein the thermosetting resin composition according to any one of claims 1 to 6 is applied. A substrate, wherein the resin-coated metal foil according to claim 9 is laminated.