JP2010053178A - Polyphenylene ether resin composition, prepreg, metal-clad laminate, and printed wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyphenylene ether resin composition containing a polyphenylene ether in which a terminal thereof is modified with a functional group such as an ethenylbenzyl group and which is made to possess satisfactory flame retardancy while maintaining a high Tg using a non-halogenated flame retardant. <P>SOLUTION: This polyphenylene ether resin composition is one comprising (A) a polyphenylene ether resin represented by Formula (I) (wherein X is aryl; (Y)<SB>m</SB>is a polyphenylene ether portion; R<SP>1</SP>to R<SP>3</SP>are each independently hydrogen, alkyl, alkenyl or alkynyl; n is an integer of 1 to 6; and q is an integer of 1 to 4) and having a number-average molecular weight of 500 to 7,000, (B) a crosslinking-type curing agent, (C) a phosphinic acid salt-based flame retardant, and (E) a curing catalyst. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a polyphenylene ether resin composition, a prepreg, a metal-clad laminate, and a printed wiring board that are preferably used as an insulating material for a printed wiring board.

  In recent years, along with improvements in bonding and mounting technology, electronic devices have been continuously developed along with higher integration of semiconductor devices mounted on electronic devices, more precise packages, and higher density of printed wiring boards. In particular, progress is significant in electronic devices that use a high frequency band such as mobile communication.

  In the printed wiring board constituting this type of electronic equipment, multilayering and fine wiring are simultaneously progressing. Reducing the dielectric constant of the material is effective for increasing the signal transmission speed required for high-speed information processing, and there is little dielectric loss tangent (dielectric loss) in order to reduce loss during transmission. It is effective to use materials.

  Since polyphenylene ether resin (PPE) is excellent in high frequency characteristics (dielectric characteristics) such as dielectric constant and dielectric loss, it is suitable as a material for printed wiring boards of electronic equipment using a high frequency band. However, since PPE generally has a high melting point, when a prepreg used to produce a normal multilayer printed wiring board is formed using PPE, the melt viscosity of the prepreg increases, and molding such as voids and blurring occurs during multilayer molding. There was also a problem that a defect occurred and a highly reliable multilayer board could not be obtained.

As a method for solving such a problem, a resin composition in which the fluidity of a molten resin is improved by using PPE having a low molecular weight is widely used. However, when the molecular weight of PPE is reduced, there is a problem that the heat resistance of the resulting laminate is lowered. In order to solve such problems, the inventor of the present application uses an ethenylbenzyl group as a polyphenylene ether resin composition that can obtain a laminate having high heat resistance even when PPE having a low molecular weight is used. A polyphenylene ether resin composition containing a polyphenylene ether modified with a radical reactive functional group as described above and a cross-linking curing agent has been developed and has already been filed for patent (Patent Document 1 below).
International Publication No. 2004/67634 Pamphlet Japanese Patent No. 3886053 JP 2006-63157 A

  Conventionally, brominated flame retardants have been widely used as flame retardants for polyphenylene ether resin compositions. However, bromine-based flame retardants containing halogen are considered to have a high environmental load, and there is a need for flame retardant formulations that substitute for brominated flame retardants.

  In a flame retardant formulation of a polyphenylene ether resin composition, phosphorus flame retardants such as phosphazene flame retardants are known as flame retardants to replace bromine flame retardants (for example, Patent Document 2).

  When a phosphazene-based flame retardant is blended with the polyphenylene ether resin composition, the polyphenylene ether resin composition and the phosphazene-based flame retardant are too compatible with each other. It was. In order to solve such a problem, a phosphazene flame retardant having a reduced compatibility with a polyphenylene ether resin composition is also known (for example, Patent Document 3). However, the phosphazene flame retardant having a reduced compatibility as described in Patent Document 3 has a relatively low phosphorus content, so that it has a relatively large number of difficulties in providing sufficient flame retardancy. It was necessary to add a flame retardant. In such a case, the original characteristics of the PPE cannot be maintained, resulting in a decrease in heat resistance or a decrease in dielectric characteristics.

  In particular, polyphenylene ether modified with a functional group such as an ethenylbenzyl group having radical reactivity as described in Patent Document 1 has a relatively high reactivity with a cross-linking curing agent. In the case of a general polyphenylene ether resin composition, since the curing reaction takes a relatively long time, the flame retardant re-aggregates at the time of molding and the compatibility is moderately reduced. However, in polyphenylene ether modified with a functional group such as ethenylbenzyl having radical reactivity, the dispersed flame retardant can be cured in a relatively short time while maintaining a highly compatible state during dispersion. To do. Therefore, when a flame retardant having excellent compatibility, such as a phosphazene flame retardant, is used, there is a problem that the heat resistance is greatly lowered.

  In view of the above problems, the present invention provides a polyphenylene ether resin composition containing a polyphenylene ether having a terminal modified with a functional group such as an ethenyl benzyl group, with sufficient flame retardancy and high glass transition temperature (Tg). It aims at providing the polyphenylene ether resin composition which can obtain the hardened | cured material provided.

  The polyphenylene ether resin composition of the present invention comprises (A) the following general formula (I):

[Wherein, X represents an aryl group, (Y) _m represents a polyphenylene ether moiety, R ^{1 to} R ³ independently represent a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group, and n represents 1 to 6 Q represents an integer of 1 to 4. And a polyphenylene ether resin having a number average molecular weight of 500 to 7000, (B) a crosslinkable curing agent, (C) a phosphinate flame retardant, and (E) a curing catalyst. And In a polyphenylene ether resin composition containing a polyphenylene ether resin modified with a functional group having radical reactivity as described above, by adding a phosphinate flame retardant, the glass transition temperature is not significantly reduced. Sufficient flame retardancy can be imparted.

  As the cross-linking type curing agent, trialkenyl isocyanurate is preferable because it can impart higher heat resistance.

  The prepreg of the present invention is obtained by impregnating a fibrous base material with any of the above polyphenylene ether resin compositions.

  In addition, the metal-clad laminate of the present invention is obtained by laminating a metal foil on the prepreg and molding by heating and pressing.

  The printed wiring board of the present invention is obtained by forming a circuit by partially removing the metal foil on the surface of the metal-clad laminate.

  According to the present invention, in a polyphenylene ether resin composition containing a polyphenylene ether modified with a radical reactive functional group such as an ethenylbenzyl group, sufficient flame retardancy is maintained while maintaining a high glass transition temperature (Tg). A polyphenylene ether resin composition that gives a cured product having the above can be obtained.

  The polyphenylene ether resin (A) in the present invention has the following general formula (I):

[Wherein, X represents an aryl group, (Y) _m represents a polyphenylene ether moiety, R ^{1 to} R ³ independently represent a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group, and n represents 1 to 6 Q represents an integer of 1 to 4. And a polyphenylene ether resin having a number average molecular weight of 500 to 7000.

The above “aryl group” means an aromatic hydrocarbon group. Examples of such “aryl group” include a phenyl group, a biphenyl group, an indenyl group, and a naphthyl group, and a phenyl group is preferable. Further, a diphenyl ether group in which these aryl groups are bonded with an oxygen atom, a benzophenone group bonded with a carbonyl group, or the like, a 2,2-diphenylpropane group bonded with an alkylene group, and the like are also included. These aryl groups may be substituted with a general substituent such as an alkyl group (preferably a C ₁ -C ₆ alkyl group, particularly a methyl group), an alkenyl group, an alkynyl group, or a halogen atom. However, since the “aryl group” is substituted on the polyphenylene ether moiety through an oxygen atom, the number of general substituents depends on the number of polyphenylene ether moieties.

  The “polyphenylene ether moiety” is composed of a phenyloxy repeating unit, and this phenyl group may be substituted with a general substituent. Examples of such “polyphenylene ether moiety” include those represented by the following general formula (II).

[Wherein, R ^{4 to} R ⁷ independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, or an alkenylcarbonyl group, and m represents an integer of 1 to 100. ].
Here, if there is an unsaturated hydrocarbon-containing group such as vinyl group, 2-propylene group (allyl group), methacryloyl group, acryloyl group, 2-propyne group (propargyl group) in the side chain of the polyphenylene ether part, The effect of the crosslinking curing agent can be utilized more effectively.

  Here, m is adjusted so that the number average molecular weight of the polyphenylene ether (I) is in the range of 1000 to 7000.

“Alkyl group” means a saturated hydrocarbon group, preferably a C ₁ -C ₁₀ alkyl group, more preferably a C ₁ -C ₆ alkyl group, more preferably a C ₁ -C ₄ alkyl group, particularly preferably Is a C ₁ -C ₂ alkyl group. Examples of such an alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group.

“Alkenyl group” means an unsaturated hydrocarbon group having at least one carbon-carbon double bond in the structure, preferably a C ₂ -C ₁₀ alkenyl group, more preferably a C ₂ -C ₆ alkenyl group. A group, particularly preferably a C ₂ -C ₄ alkenyl group. Examples of such alkenyl groups include ethylene, 1-propylene, 2-propylene, isopropylene, butylene, isobutylene, pentylene, and hexylene.

“Alkynyl group” means an unsaturated hydrocarbon group having at least one carbon-carbon triple bond in the structure, preferably a C ₂ -C ₁₀ alkynyl group, more preferably a C ₂ -C ₆ alkynyl group. Particularly preferred is a C ₂ -C ₄ alkynyl group. Examples of such alkynyl groups include ethyne, 1-propyne, 2-propyne, isopropyne, butyne, isobutyne, pentyne and hexyne.

  The “alkenylcarbonyl group” refers to a carbonyl group substituted by the alkenyl group, and examples thereof include an acryloyl group and a methacryloyl group.

  In PPE (I), a preferable value of n is an integer of 1 to 4, more preferably 1 or 2, and most preferably 1. Further, q is preferably an integer of 1 to 3, more preferably 1 or 2, and most preferably 1. In addition, although the value of m is an integer of 1-100, since it is necessary to make the number average molecular weight of PPE (I) at least 1000-7000 in the present invention, the number average molecular weight of the target PPE (I) Accordingly, it is necessary to adjust the value of m. That is, depending on the value of m, the molecular weight of PPE (I) may be less than 1000 or exceed 7000, but if the number average molecular weight of the entire PPE (I) contained in the PPE resin composition is 1000 to 7000, Often, at this point, m may not be a fixed value but a variable within a certain range.

  The following partial structure in PPE (I):

N = 1 and R ^{1 to} R ³ are p-ethenylbenzyl group or m-ethenylbenzyl group which is a hydrogen atom, the interaction with the cross-linking curing agent is particularly good, Even if a large amount of a crosslinking type curing agent is not added, heat resistance is not reduced and a low dielectric constant can be achieved. In particular, PPE having only a p-ethenylbenzyl group at the terminal has a high melting point and a high softening point, whereas PPE having both a p-ethenylbenzyl group and an m-ethenylbenzyl group at the terminal has a low melting point. It becomes a low softening point. Therefore, the melting point and softening point of PPE can be arbitrarily changed by adjusting the ratio of the p-ethenylbenzyl group and the m-ethenylbenzyl group.

  The number average molecular weight of the polyphenylene ether resin (A) is 1000 to 7000. If it exceeds 7000, the fluidity at the time of molding will be reduced, making multilayer molding difficult, and if it is less than 1000, the original excellent dielectric properties and heat resistance of the PPE resin will not be expressed constantly. Because there is a possibility. In order to further exhibit such excellent fluidity, heat resistance and dielectric properties, the number average molecular weight is preferably 1200 or more and 5000 or less, more preferably 1500 or more and 4500 or less.

  The polyphenylene ether resin (A) can be produced by a known method as disclosed in, for example, WO 2004/67634.

  Since the polyphenylene ether resin (A) has a low molecular weight, a PPE resin composition excellent in fluidity can be obtained.

  The crosslinkable curing agent (B) in the present invention three-dimensionally crosslinks the polyphenylene ether resin (A), and maintains the heat resistance of the cured product even when a low molecular weight polyphenylene ether is used. It has an effect. As such a cross-linking type curing agent, those particularly having good compatibility with PPE are used. Polyfunctional vinyl compounds such as divinylbenzene, divinylnaphthalene and divinylbiphenyl; synthesized from the reaction of phenol and vinylbenzyl chloride. Vinylbenzyl ether compounds; styrene monomers, allyl ether compounds synthesized from the reaction of phenol and allyl chloride; and trialkenyl isocyanurates are good. Trialkenyl isocyanurate having good compatibility is particularly good, and specifically, triallyl isocyanurate (hereinafter referred to as TAIC) and triallyl cyanurate (hereinafter referred to as TAC) are preferable. This is because a laminated sheet having a low dielectric constant and high heat resistance and reliability can be obtained.

  Moreover, it is preferable to use a (meth) acrylate compound (methacrylate compound and acrylate compound) as the crosslinking type curing agent of the present invention. In particular, it is preferable to contain 3 to 20% by mass of a 3-5 functional (meth) acrylate compound based on the total amount of the PPE resin composition. Trimethylolpropane trimethacrylate (TMPT) or the like can be used as the 3-5 functional methacrylate compound, while trimethylolpropane triacrylate or the like can be used as the 3-5 functional acrylate compound. If these crosslinkable curing agents are added, the heat resistance of the finally obtained laminate can be further increased.

  In addition, although (meth) acrylate compounds having a functional group number other than 3 to 5 may be used, the heat resistance of the laminate is improved by using a (meth) acrylate compound having a functional group number of 3 to 5 as described above. The degree to let it be high. Moreover, even if it uses a 3-5 functional (meth) acrylate compound, when these compounding quantities are less than 3 mass% with respect to PPE resin composition whole quantity, the effect of the heat resistance improvement of a laminated board is fully enough. There is a possibility that it cannot be obtained, and conversely, if it exceeds 20% by mass, the dielectric properties and moisture resistance may be lowered.

  The blending ratio of the polyphenylene ether resin (A) and the crosslinkable curing agent (B) is preferably 30/70 to 90/10 in parts by mass. If the polyphenylene ether resin (A) is less than 30 parts by mass, the laminate may be brittle. If the polyphenylene ether resin (A) exceeds 90 parts by mass, the heat resistance may be reduced. The blending ratio of the polyphenylene ether resin (A) and the crosslinkable curing agent (B) is preferably 50/50 to 90/10, and more preferably 60/40 to 90/10.

  In the present invention, the phosphinate flame retardant (C) is represented by the following general formula (IV) or (V):

(Wherein R ₁ and R ₂ may be the same or different from each other, a hydrogen atom, an alkyl group having 1 to 16 carbon atoms, an alkyl group containing an ether bond having 1 to 16 carbon atoms, an aryl group) , An aralkyl group, and a cycloalkyl group, R ₃ represents a divalent organic group, n represents an integer of 1 to 4, and M represents 1 to 4 Mg, Ca, Al, and Sb. , Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, K, and / or a protonated nitrogen base.
The thing represented by these is preferable.

  The average particle diameter of the phosphinate flame retardant (C) is preferably in the range of 0.5 to 10 μm from the viewpoint of excellent surface smoothness and insulating properties of the substrate. The average particle diameter is a value measured by dispersing in a liquid using a laser diffraction particle size distribution measurement method.

  Moreover, it is preferable from the point of insulation resin design that it is 5-40 mass% as phosphorus content rate of a phosphinate. When the phosphorus content is too small, it is necessary to add a large amount in order to impart sufficient flame retardancy. In this case, the characteristics of the PPE resin are not fully exhibited. Moreover, when there is too much the said phosphorus content rate, reactivity may be inhibited or reliability may fall.

  The amount of the phosphinate flame retardant (C) is such that the phosphorous concentration is 0.5 to 5% by mass, further 1 to 3% by mass in the total amount of the organic components of the polyphenylene ether resin composition. It is preferable to contain.

  Moreover, unless the effect of this invention is impaired, you may mix | blend phosphorus compounds, such as other phosphate ester type flame retardants, with a phosphinate flame retardant (C) as a flame retardant. Specific examples of such phosphorus compounds include, for example, phosphazene flame retardants, triphenyl phosphate, cresyl diphenyl phosphate, tricresyl phosphate, phosphate esters, condensed phosphate esters with phenol compounds, and condensed phosphate esters. And flame retardants, monophosphate ester flame retardants and the like. In this case, the other phosphorus compound is preferably 60% or less in the total amount with the phosphinate flame retardant (C).

  In addition, a reaction initiator may be added to the PPE resin composition of the present invention in order to more effectively exhibit the action and effect of the crosslinkable curing agent. Even with only the polyphenylene ether resin (A) and the crosslinkable curing agent (B), curing can proceed at a high temperature, but depending on the process conditions, it may not be possible to increase the temperature until curing proceeds. It is preferable to add a reaction initiator. Such “reaction initiator” is not particularly limited as long as it can improve the properties such as heat resistance of the PPE resin by promoting the curing of the PPE resin composition at an appropriate temperature and time. For example, α, α′-bis (t-butylperoxy-m-isopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) -3-hexyne, benzoyl peroxide, 3,3 Oxidation like ', 5,5'-tetramethyl-1,4-diphenoquinone, chloranil, 2,4,6-tri-t-butylphenoxyl, t-butylperoxyisopropyl monocarbonate, azobisisobutyronitrile It is preferable to use an agent. If necessary, a carboxylic acid metal salt can be further added to further accelerate the curing reaction. Among the above reaction initiators, α, α′-bis (t-butylperoxy-m-isopropyl) benzene is particularly suitable. Since the reaction start temperature is relatively high, it is difficult to promote curing when curing is not required, such as when prepreg drying, and the preservability of the PPE resin composition is not given up. This is because it does not volatilize and has good stability.

  The polyphenylene ether resin composition of the present invention may further contain an inorganic filler as necessary for the purpose of enhancing dimensional stability during heating or enhancing flame retardancy.

  Specific examples of the inorganic filler include silica, alumina, talc, aluminum hydroxide, magnesium hydroxide, titanium oxide, mica, aluminum borate, barium sulfate, calcium carbonate, and the like.

  Further, as the inorganic filler, those which are surface-treated with an epoxy silane type or amino silane type silane coupling agent are particularly preferable. A metal-clad laminate obtained by using a polyphenylene ether resin composition containing an inorganic filler surface-treated with a silane coupling agent as described above has high heat resistance during moisture absorption and also has an interlayer peel strength. Tend to be higher.

  The blending ratio of the inorganic filler is 10 to 100 parts by mass, and further 20 to 50 parts by mass with respect to 100 parts by mass of the total amount of the polyphenylene ether resin (A) and the crosslinkable curing agent (B). However, it is preferable from the viewpoint of improving the dimensional stability without deteriorating the fluidity and the adhesion to the metal foil.

  In the polyphenylene ether resin composition of the present invention, additives such as a heat stabilizer, an antistatic agent, an ultraviolet absorber, a dye, a pigment, a lubricant and the like are blended as necessary within a range not impairing the effects of the present invention. May be.

  The polyphenylene ether resin composition of the present invention is prepared in a varnish form. Such a varnish is prepared as follows, for example.

  The crosslinkable curing agent (B) is blended and dissolved in the polyphenylene ether (A) resin solution. At this time, heating may be performed as necessary.

  Furthermore, the phosphinic acid salt flame retardant (C), the curing catalyst (E), and other flame retardants and inorganic fillers used as necessary are added, and a ball mill, a bead mill, a planetary mixer, a roll mill, etc. are used. The varnish-like polyphenylene ether resin composition is prepared by dispersing until a predetermined dispersion state is obtained.

  Examples of a method for producing a prepreg using the obtained polyphenylene ether resin composition include a method in which a fibrous base material is impregnated with a polyphenylene ether resin composition and then dried.

  Examples of the fibrous base material 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 at 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.

  Impregnation is performed by dipping or coating. The impregnation can be repeated a plurality of times as necessary. In this case, it is also possible to repeat the impregnation using a plurality of solutions having different compositions and concentrations, and finally adjust to a desired composition and resin amount.

  The base material impregnated with the polyphenylene ether resin composition is heated at a desired heating condition, for example, at 80 to 170 ° C. for 1 to 10 minutes, whereby a semi-cured (B stage) prepreg is obtained.

  As a method for producing a metal-clad laminate using the prepreg thus obtained, one or a plurality of the prepregs are stacked, and a metal foil such as a copper foil is stacked on both upper and lower surfaces or one surface thereof. By heating and pressing to laminate and integrate, a double-sided metal foil-clad laminate or a single-sided metal foil-clad laminate can be produced. The heating and pressing conditions can be appropriately set depending on the thickness of the laminate to be manufactured, the type of the resin composition of the prepreg, etc. For example, the temperature is 170 to 210 ° C., the pressure is 3.5 to 4.0 Pa, and the time For 60 to 150 minutes.

  And the printed wiring board which provided the conductor pattern as a circuit on the surface of a laminated body can be obtained by carrying out the etching process etc. of the metal foil on the surface of the produced laminated body.

  According to the present invention, in a polyphenylene ether resin composition containing a polyphenylene ether modified with a radical reactive functional group such as an ethenylbenzyl group, by using a phosphinate flame retardant (C) as a flame retardant. A cured product that maintains a high glass transition temperature (Tg) while imparting sufficient flame retardancy can be obtained.

  The present invention will be described more specifically with reference to the following examples. However, the scope of the present invention is not limited to these examples.

(Production example: Production of polyphenylene ether having an ethenylbenzyl group and a number average molecular weight of about 3,500)
Production of low molecular weight PPE (PPE-1) First, the molecular weight of PPE was adjusted. 100 parts by weight of PPE (manufactured by SABIC Japan Co., Ltd .: trade name “Noryl PX9701”, number average molecular weight 14000), 4.28 parts by weight of 2,6-dimethylphenol as a phenol species, and t-butylperoxyisopropyl monocarbonate as an initiator (Nippon Yushi Co., Ltd. product name: “Perbutyl I”) 2.94 parts by mass and cobalt naphthenate 0.0042 parts by mass were mixed and mixed. Using 250 parts by mass of toluene as a solvent, the mixture was mixed at 80 ° C. for 1 hour, and stirred for dispersion or dissolution. After completion of the reaction, a large amount of methanol was added to reprecipitate the PPE, impurities were removed, and the solvent was completely removed by drying at 80 ° C./3 hours under reduced pressure. The PPE obtained after this treatment had a number average molecular weight of about 2400 as measured by gel permeation chromatograph (GPC).

  Next, the terminal hydroxyl group of the low molecular weight PPE was capped with an ethenylbenzyl group. In a 1 liter three-necked flask equipped with a temperature controller, a stirrer, a cooling facility, and a dropping funnel, 200 parts by mass of the above-mentioned PPE reduced in molecular weight, chloromethylstyrene (p-chloromethylstyrene and m-chloromethylstyrene) Ratio was 50/50, manufactured by Tokyo Chemical Industry Co., Ltd.) 14.51 parts by mass, tetra-n-butylammonium bromide 0.818 parts by mass, and toluene 400 parts by mass. The mixture was dissolved by stirring, and the liquid temperature was adjusted to 75 ° C. A sodium hydroxide aqueous solution (11 g of sodium hydroxide / 11 g of water) was dropped into the mixed solution over 20 minutes, and stirring was further continued at 75 ° C. for 4 hours. Next, the flask contents were neutralized with a 10% aqueous hydrochloric acid solution, a large amount of methanol was added, and ethenylbenzylated modified PPE was reprecipitated and filtered. The filtrate was washed 3 times with a mixture of methanol 80 and water 20 and then dried under reduced pressure at 80 ° C. for 3 hours to take out the ethenylbenzylated modified PPE from which the solvent and water had been removed. When the number average molecular weight of this modified PPE was measured by gel permeation chromatography, it was about 3500.

Example 1
80 parts by mass of toluene as a solvent was added to 50 parts by mass of ethenylbenzylated low molecular weight PPE obtained in Production Example, and the mixture was mixed at 80 ° C. for 30 minutes and stirred to completely dissolve. In the PPE solution thus obtained, 50 parts by mass of TAIC (manufactured by Nippon Kasei Co., Ltd.) as a crosslinking type curing agent, 15 parts by mass of OP-935 manufactured by Clariant Japan as a phosphinate flame retardant (I), and reaction As an initiator, 2 parts by mass of α, α′-bis (t-butylperoxy-m-isopropyl) benzene (manufactured by NOF Corporation: trade name “Perbutyl P”) was blended. Furthermore, 35 parts by mass of spherical silica (manufactured by Admatechs Co., Ltd .: trade name “SO25R”) is added as an inorganic filler, and this is mixed, dispersed and dissolved in toluene as a solvent to obtain a varnish of the resin composition. Obtained.

  Next, after impregnating a glass cloth (“WEA116E” manufactured by Nitto Boseki Co., Ltd.) with the varnish of the obtained resin composition, it was heated and dried at 150 ° C. for 3 to 5 minutes to obtain a prepreg.

  Next, 6 sheets of the obtained prepregs were stacked and laminated, and copper foils (F2-WS 18 μm manufactured by Furukawa Circuit Foil Co., Ltd.) were disposed on both outer layers, respectively, under conditions of a temperature of 220 ° C. and a pressure of 3 MPa. By heating and pressing, a copper-clad laminate having a thickness of 0.75 mm was obtained.

  The following evaluation was performed using the obtained prepreg and copper clad laminate.

<Dielectric properties>
In accordance with the standard of IPC TM-650 2.5.5.9, the dielectric constant and dielectric loss tangent of the copper-clad laminate at 1 GHz were determined.

<Coefficient of thermal expansion>
The thermal expansion coefficient in the Z-axis direction of the copper clad laminate was measured by the TMA method.

<Glass-transition temperature>
The glass transition temperature (Tg) of the copper-clad laminate was measured using a viscoelastic spectrometer “DMS100” manufactured by Seiko Instruments Inc. At this time, measurement was performed with a bending module at a frequency of 10 Hz, and the temperature at which tan δ reached a maximum when the temperature was raised from room temperature to 280 ° C. under a temperature rising rate of 5 ° C./min was defined as the glass transition temperature (Tg).

<Thermal decomposition temperature>
The pyrolysis temperature (Td) of the copper clad laminate was measured using a pyrolysis weight measuring device “TG / DTA320” manufactured by Seiko Instruments Inc. The temperature increase rate at this time was 5 ° C./min, and the temperature at which 5% weight decreased when the temperature was increased from room temperature to 500 ° C. was defined as the thermal decomposition temperature.

<Flame retardance>
The flame retardancy of the copper clad laminate cut out to a predetermined size was determined by performing a combustion test according to the UL 94 combustion test method.

(Examples 2 and 3 and Comparative Examples 1 and 2)
A polyphenylene ether resin composition was prepared and evaluated in the same manner as in Example 1 except that the blending composition shown in Table 1 was used. In Example 2, instead of the phosphinate flame retardant (I), OP930 manufactured by Clariant Japan Co. was used as the phosphinate flame retardant (II). In Comparative Example 1, the phosphinate flame retardant SPS-100 manufactured by Otsuka Chemical Co., Ltd. was used as the phosphazene flame retardant (I) instead of (I), and SPR-100 manufactured by Otsuka Chemical Co., Ltd. was used as the phosphazene flame retardant (II) in Comparative Example 2. It was.

  The results are shown in Table 1.

  All of the PPE resin compositions of Examples 1 to 3 using a phosphinate flame retardant as the flame retardant maintained a high Tg, and thereby had a low coefficient of thermal expansion. On the other hand, in Comparative Examples 1 and 2 using a phosphazene flame retardant, both Tg was low and the coefficient of thermal expansion was also high.

Claims (5)

(A) The following general formula (I):

[Wherein, X represents an aryl group, (Y) _m represents a polyphenylene ether moiety, R ^{1 to} R ³ independently represent a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group, and n represents 1 to 6 Q represents an integer of 1 to 4. ]
And a polyphenylene ether resin having a number average molecular weight of 500 to 7000, (B) a crosslinkable curing agent, (C) a phosphinate flame retardant, and (E) a curing catalyst. A polyphenylene ether resin composition.   The polyphenylene ether resin composition according to claim 1, wherein the crosslinking curing agent is trialkenyl isocyanurate.   A prepreg obtained by impregnating a fibrous base material with the polyphenylene ether resin composition according to claim 1.   A metal-clad laminate obtained by laminating a metal foil on the prepreg according to claim 3 and heating and pressing.   A printed wiring board obtained by forming a circuit by partially removing the metal foil on the surface of the metal-clad laminate according to claim 4.