JPH08231847A - Polyphenylene oxide resin composition and prepreg and laminate prepared by using the same - Google Patents

Abstract

PURPOSE: To obtain a polyphenylene oxide resin composition which can gave a laminate and a prepreg excellent in water resistance, heat resistance and dimensional stability by adding a solvent to a mixture comprising a polyphenylene oxide, triallyl isocyanurate, a compatibilizer and a specified flame retardant. CONSTITUTION: This composition is prepared by adding a solvent to a mixture comprising a polyphenylene oxide, triallyl isocyanurate, a compatibilizer and a flame retardant (a brominated organic compound inert to the polyphenylene oxide and triallyl isocyanurate). The flame retardant used should not be soluble in the solvent but should be dispersed therein. It is desirable that the brominated organic compound used as the flame retardant has a true density of 3.0 or below.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant polyphenylene oxide resin composition useful as an insulating material for printed wiring boards, a prepreg using the polyphenylene oxide resin composition, and a laminated board using the prepreg. Regarding

[0002]

2. Description of the Related Art In recent years, electronic equipment has made a great progress due to high integration of semiconductor devices to be mounted and refinement of packages, high density wiring and bonding of printed wiring boards, and improvement of mounting technology. In particular, the progress has been remarkable in electronic devices using high frequency bands such as mobile communication.

In the printed wiring board which constitutes this kind of electronic equipment, the multilayered wiring and the fine wiring are progressing at the same time. However, in order to increase the signal transmission speed required for high speed information processing, the printed wiring board is required. Impedance control is essential, and the higher the frequency band, the higher the demand. The quality of impedance control of this printed wiring board depends on the dimensional accuracy such as the circuit width and the circuit interval. However, in a laminated board made of a resin composition containing a conventional flame retardant, the dimensional stability is poor because the thermal expansion coefficient is large, and therefore the circuit width, the circuit interval, etc. vary, and the design dimensional accuracy cannot be ensured. Impedance control was not enough.

Printed wiring boards for electronic equipment which utilize such a demanded high frequency band are also called polyphenylene oxide resin [polyphenylene ether (PPE) resin because of their excellent high frequency characteristics such as permittivity and dielectric loss. ]
Was suitable, but the heat resistance and dimensional stability were not sufficient.

[0005]

DISCLOSURE OF THE INVENTION Therefore, the inventors of the present application have disclosed in Japanese Patent Application No. 5-236893 a polyphenylene oxide resin composition having improved heat resistance and dimensional stability, and the polyphenylene oxide resin. A method for producing a prepreg using the composition and a method for producing a laminated board using the prepreg have been disclosed. That is, polyphenylene oxide, triallyl isocyanurate, a polyphenylene oxide resin composition containing a reactive brominated compound having a monomaleimide group that reacts with triallyl isocyanurate, and a prepreg using this polyphenylene oxide resin composition. And a method for manufacturing a laminated board using this prepreg.
However, when a polyphenylene oxide-triallyl isocyanurate system is made to contain a soluble brominated compound such as a reaction type or an addition type as a flame retardant, it has an effect on heat resistance and dimensional stability. However, the water resistance, moisture resistance, heat resistance after moisture absorption, glass transition point (Tg), etc. of the laminate were not at a satisfactory level.
That is, since the heat resistance to moisture absorption and the glass transition point (Tg) are low, and the water absorption rate and the moisture absorption rate are high, there is a tendency that a problem occurs during component mounting.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a polyphenylene oxide resin composition having improved water resistance, moisture resistance, moisture absorption heat resistance, and glass transition point, and this polyphenylene oxide composition. An object of the present invention is to provide a prepreg using an oxide resin composition and a laminate using the prepreg.

[0007]

The polyphenylene oxide resin composition according to claim 1 of the present invention comprises a polyphenylene oxide resin composition containing polyphenylene oxide, triallyl isocyanurate, a compatibilizing agent and a flame retardant as a solvent. In the varnish to which is added, the flame retardant is a brominated organic compound that does not react with polyphenylene oxide and triallyl isocyanurate, and is dispersed in the solvent without being dissolved.

The polyphenylene oxide resin composition according to claim 2 of the present invention is characterized in that the true specific gravity of the brominated organic compound is 3.0 or less.

In the polyphenylene oxide resin composition according to claim 3 of the present invention, the brominated organic compound is represented by decabromodiphenylethane represented by the following general formula [1] or represented by the following general formula [2]. 4,4-dibromobiphenyl as described above.

[0010]

Embedded image

[0011]

[Chemical 4]

A polyphenylene oxide resin composition according to a fourth aspect of the present invention comprises a polyphenylene oxide 3
0 to 60 parts by weight, 35 to triallyl isocyanurate
It is contained in a proportion of 62 parts by weight, and the content of bromine is 8 to 20 with respect to the total amount of the polyphenylene oxide resin composition.
It is characterized by containing the said brominated organic compound which is weight%.

A prepreg according to a fifth aspect of the present invention is obtained by impregnating a substrate with the polyphenylene oxide resin composition according to any of the first to fourth aspects, heating and drying, and semi-curing.

The laminated plate according to claim 6 of the present invention is formed by laminating and molding a predetermined number of prepregs according to claim 5 by heating and pressing.

The present invention will be described in detail below. Polyphenylene oxide used in the present invention (hereinafter referred to as PP
(Also referred to as O) [also referred to as polyphenylene ether (PPE)] is represented by, for example, the following general formula [3].

[0016]

Embedded image

An example of PPO represented by the above general formula [3] is poly (2,6) represented by the following general formula [4].
-Dimethyl-1,4-phenylene oxide) and the like.

[0018]

[Chemical 6]

Such PPO is, for example, USP4.
It can be synthesized by the method disclosed in the specification of 059,568. Although not particularly limited, for example,
Weight average molecular weight (Mw) is 46,000-53,000.
Then, PPO having a ratio with the number average molecular weight (Mn), that is, a molecular weight distribution (Mw / Mn) of 4.0 to 4.5 is preferable. Originally PPO is a thermoplastic resin, and in order to improve heat resistance and dimensional stability, PPO and styrene / butadiene block copolymer, styrene / isoprene block copolymer, 1,2-polybutadiene, 1,4-
It is used as a PPO resin composition containing at least one compatibilizer selected from the group consisting of polybutadiene, malein-modified polybutadiene, acrylic-modified polybutadiene, and epoxy-modified polybutadiene, and triallyl isocyanurate (hereinafter referred to as TAIC). TAI
C is a monomer thereof (hereinafter referred to as m-TAIC) and / or a prepolymer thereof (hereinafter referred to as p-TAIC).
Is used.

The characteristics of the PPO resin composition of the present invention are that PP
For the purpose of improving the water resistance, moisture resistance, moisture absorption heat resistance and glass transition point of a laminate using the O resin composition, the PPO
PPO containing compatibilizer and flame retardant in TAIC and TAIC
In the varnish obtained by adding a solvent to the resin composition, the flame retardant is a brominated organic compound that does not react with PPO and TAIC, and is dispersed in the solvent without being dissolved in the solvent. That is, thermoplastic PPO and thermosetting TAI
When mixed with C and cured, the interpenetrating network structure [IP
N (Interpenetrating Polymer Net Work)],
It has an extremely excellent structure as a laminate having high heat resistance. However, when the flame retardant is a reactive flame retardant having an unsaturated bond or a soluble flame retardant that dissolves in the solvent, the flame retardant penetrates into the IPN of PPO-TAIC and the IPN Of the TAIC, resulting in a large amount of unpolymerized residue of TAIC, and the water resistance, moisture resistance, moisture absorption heat resistance and glass transition point of the prepreg using this PPO resin composition and the laminate using this prepreg. (Hereinafter referred to as Tg) is reduced.

Therefore, the flame retardant is PPO and TAI.
Since it is a brominated organic compound that does not react with C, and is not dissolved in the solvent and dispersed therein, the flame retardant is present as a filler in the resin, so that the IPN of PPO-TAIC
It is presumed that the water resistance, moisture resistance, moisture absorption heat resistance, and Tg are improved because TAIC is almost completely cured to form good IPN without inhibiting the formation of water. Furthermore, the true specific gravity of the brominated organic compound is preferably 3.0 or less. That is, when the true specific gravity of the brominated organic compound, which is a flame retardant, exceeds 3.0, the flame retardant tends to settle in the varnish of the PPO resin composition, and if it is not always stirred, a uniform varnish is obtained. Is not obtained, and the workability deteriorates.

For example, as the brominated organic compound,
Examples include decabromodiphenylethane represented by the general formula [1] and 4,4-dibromobiphenyl represented by the general formula [2].

30 to 60 parts by weight of PPO and 3 parts of TAIC
It is preferably contained in a proportion of 5 to 62 parts by weight. That is, when PPO is less than 30 parts by weight and TAIC is more than 62 parts by weight, the laminate becomes brittle, and when PPO is more than 60 parts by weight and TAIC is less than 35 parts by weight, It is not possible to form a sufficient IPN. Further, it is preferable to contain the brominated organic compound having a bromine content of 8 to 20% by weight based on the total amount of the PPO resin composition. That is, when the content of bromine is less than 8% by weight with respect to the total amount of the PPO resin composition, the flame retardancy of the laminated plate is reduced, and the flame retardance at the level of UL standard 94V-0 cannot be maintained. When it exceeds 20% by weight, bromine (Br) is dissociated during heat and pressure molding for producing a laminated plate and deposited on the surface of the laminated plate, so that the heat resistance tends to decrease.

In order to obtain a prepreg by impregnating a base material, the PPO resin composition of the present invention first comprises PPO, TAIC, the brominated organic compound, and the compatibilizer, which is optionally added, as an organic solvent. Are mixed to prepare a varnish and used. The organic solvent is not particularly limited as long as it does not dissolve the brominated organic compound, dissolves the resin component, and does not adversely affect the reaction, and examples thereof include ketones such as methyl ethyl ketone and ethers such as dibutyl ether. Or a mixture of two or more suitable organic solvents such as ethyl acetate, esters such as ethyl acetate, amides such as dimethylformamide, chlorinated hydrocarbons such as trichloroethylene. The concentration of the resin solid content of the varnish may be appropriately adjusted according to the operation of impregnating the base material with the varnish, and for example, 50 to 90% by weight is suitable.

A substrate is impregnated with the varnish prepared as described above, and then dried by heating to evaporate the organic solvent to obtain a prepreg. As the base material, a woven or non-woven fabric of organic fibers or glass fibers is used. The amount of impregnation into this substrate is
It is preferable that the weight ratio of the resin solid content in the prepreg is 35% by weight or more. Generally, the dielectric constant of the base material is higher than that of the resin, and therefore, in order to reduce the dielectric constant of the laminate obtained by using this prepreg, the content of the resin solid content in the prepreg should be less than the above weight ratio. It is good to have many. For example, a prepreg using an E glass cloth as a base material can achieve a dielectric constant of 3.7 or less at a resin solid content of 37% by weight or more, and a prepreg using a D glass cloth as a base material has a dielectric constant of 45 or less. A dielectric constant of 3.2 or less can be achieved at a resin solid content of not less than wt%.

In the present invention, a laminated board can be produced using the above prepreg. More specifically, one or a plurality of prepregs of the present invention are stacked, and further, a metal foil such as a copper foil is stacked on both upper and lower surfaces or one surface of the prepreg, which is heat-pressed to form a laminated and integrated double-sided metal. Foil- or single-sided metal foil-clad laminates can be made. A printed wiring board can be obtained by forming a circuit by etching the metal foil of this laminated board, and further, this printed wiring board is used as an inner layer printed wiring board, with the prepreg of the present invention interposed therebetween. A multi-layer printed wiring board can be produced by stacking a plurality of sheets and stacking a metal foil on the outermost layer thereof and performing heat-press molding. The molding conditions vary depending on the mixing ratio of the raw materials of the resin composition of the present invention and are not particularly limited, but generally 170 ° C or higher and 230 ° C or lower,
It is preferable to heat and pressurize at a pressure of 10 kg / cm ² or more and 50 kg / cm ² or less for an appropriate time. Further, after heating and pressurization, reheating at 150 ° C. or more and 250 ° C. or less under pressure release results in solid resin content. The curing can be accelerated.
The PPO resin composition thus obtained does not impair the properties of PPO and has excellent high-frequency properties such as dielectric properties, and also has improved water resistance, moisture resistance, moisture absorption heat resistance, and glass transition point. It was an excellent one.

As described above, a prepreg obtained by impregnating a substrate with the PPO resin composition according to the present invention, heating and drying it and semi-curing it, and heat-pressing a predetermined number of this prepreg to obtain a laminate are obtained. The laminated plate is excellent in water resistance, moisture resistance, moisture absorption heat resistance and glass transition point.

[0028]

The PPO resin composition according to claim 1 of the present invention is a varnish prepared by adding a solvent to a PPO resin composition containing PPO, TAIC, a compatibilizer and a flame retardant,
Since the flame retardant is a brominated organic compound that does not react with PPO and TAIC, and is not dissolved in the solvent but dispersed therein, it is cured by mixing thermoplastic PPO and thermosetting TAIC. Then, the mutual intrusion network structure [IPN (In
terpenetrating Polymer Net Work)], resulting in an extremely excellent structure as a laminate having high heat resistance. However, when the flame retardant is a reactive flame retardant having an unsaturated bond or a soluble flame retardant that dissolves in the solvent, the flame retardant penetrates into the IPN of PPO-TAIC and
The formation of PN is inhibited, and as a result, a large amount of unpolymerized residue of TAIC is generated, and the prepreg using this PPO resin composition and the laminated sheet using this prepreg have water resistance, moisture resistance, moisture absorption heat resistance, and glass transition. Point (hereinafter referred to as Tg)
Is reduced. Therefore, if the flame retardant is PPO and TAI,
Since it is a brominated organic compound that does not react with C, and is not dissolved in the solvent and dispersed therein, the flame retardant is present as a filler in the resin, so that the IPN of PPO-TAIC
It is presumed that the TAIC hardens almost completely and forms a good IPN without hindering the formation of

In the PPO resin composition according to claim 2 of the present invention, the true specific gravity of the brominated organic compound which is the flame retardant is 3.0.
Because of the following, the flame retardant is unlikely to settle in the varnish of the PPO resin composition, and a uniform varnish can be obtained without constant stirring during the impregnation operation on the substrate.

In the PPO resin composition according to claim 3 of the present invention, the brominated organic compound is represented by decabromodiphenylethane represented by the above general formula [1] or by the above general formula [2]. Since it is 4,4-dibromobiphenyl, it does not inhibit the formation of IPN of PPO-TAIC, and TA
It is presumed that the IC hardens almost completely and forms a good IPN.

In the PPO resin composition according to claim 4 of the present invention, 30 to 60 parts by weight of PPO and 35 to 6 of TAIC are used.
Since it is contained at a ratio of 2 parts by weight, IPN is formed, so that it has excellent heat resistance. That is, when PPO is less than 30 parts by weight and TAIC exceeds 62 parts by weight,
Laminate becomes brittle, PPO exceeds 60 parts by weight, TAI
When C is less than 35 parts by weight, sufficient IPN cannot be formed. Further, since it contains the brominated organic compound having a bromine content of 8 to 20% by weight based on the total amount of the PPO resin composition, it has excellent flame retardancy. That is, when the content of bromine is less than 8% by weight with respect to the total amount of the PPO resin composition, the flame retardancy of the laminated plate decreases, and the UL standard of 9
When it becomes impossible to maintain the flame retardancy of 4V-0 and exceeds 20% by weight, bromine (Br) is dissociated during the heat and pressure molding for producing a laminated plate and deposited on the surface of the laminated plate. Heat resistance tends to decrease.

In the prepreg according to claim 5 of the present invention,
Since the base material is impregnated with the PPO resin composition according to any one of claims 1 to 4, and the material is heated and dried to be semi-cured, it is excellent in water resistance, moisture resistance, moisture absorption heat resistance, and has a high glass transition point.

In the laminated plate according to the sixth aspect of the present invention, a predetermined number of the prepregs according to the fifth aspect are heat-pressed and laminated, so that they are excellent in water resistance, moisture resistance and moisture absorption heat resistance, and have a glass transition point. high.

[0034]

EXAMPLES The present invention will be specifically described below with reference to examples.

Example 1 As shown in the composition of Table 1, PPO represented by the above general formula [4] (manufactured by Japan GE Plastics Co., Ltd .: trade name Noryl PX9701) 4
0 parts by weight, m-TAIC (manufactured by Nippon Kasei Co., Ltd.) 45 parts by weight, p-TAIC (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd .: trade name P-TAIC-1000C) 10 parts by weight, and styrene-butadiene as a compatibilizer. 5 parts by weight of a block copolymer (made by Asahi Kasei Co., Ltd .: Toughprene A), decabromodiphenylethane represented by the above general formula [1] which is a brominated organic compound as a flame retardant (manufactured by Mitsui Toatsu Fine Co., Ltd.) : Trade name Planeron BDE, 82.3Br
%) And 21.5 parts by weight of α, α ′ bis (t-butylperoxy-m-isopropyl) benzene (manufactured by NOF CORPORATION: trade name PB-P) as an initiator. This was mixed, dispersed, and dissolved in trichloroethylene as a solvent to obtain a varnish of PPO resin composition.
Since the flame retardant was a brominated organic compound that did not react with PPO and TAIC, the flame retardant was not dissolved in the solvent but dispersed in the varnish that was the PPO resin composition. After this varnish was impregnated into E glass cloth (manufactured by Asahi Shovel Co., Ltd .: trade name 216L), the temperature was 120.
The solvent was removed by heating and drying at 5 ° C. for 5 minutes to obtain a prepreg having a resin content of 35% by weight. A copper foil (DT foil) is attached to both surfaces of this one prepreg, and the temperature is 170 ° C.
Heating and pressurizing under the molding condition of pressure 50 kg / cm ² , 180 minutes,
Then, under pressure release, it was reheated in a dryer at a temperature of 230 ° C. for 2 hours to obtain a double-sided copper-clad laminate for an inner layer printed wiring board. A pattern is formed on the double-sided copper clad laminate for this inner layer printed wiring board to form a core, and two prepregs are stacked on each of both sides of this core, and copper foil (ST foil) with a thickness of 70 μm is formed on both upper and lower sides thereof. Again, the temperature is 170
° C., a pressure 50 kg / cm ^2, heating and pressing the molding conditions of 180 minutes, then the temperature 230 ° C. in a drier under pressure relief, 2
Reheating was performed under the condition of time to obtain a double-sided copper-clad laminate for a printed wiring board. 50 mm x 5 for the obtained double-sided copper clad laminate
The sample was cut into 0 mm to obtain a sample for heat resistance against moisture absorption of a laminated plate.

Five prepregs were stacked, copper foil (ST foil) having a thickness of 70 μm was stacked on both upper and lower sides thereof, and the temperature was 170.
° C., a pressure 50 kg / cm ^2, heating and pressing the molding conditions of 180 minutes, then the temperature 230 ° C. in a drier under pressure relief, 2
Reheating was performed under the condition of time to obtain a double-sided copper-clad laminate for a printed wiring board. The copper foil on the surface of the obtained double-sided copper-clad laminate was removed by etching and cut into 50 mm × 50 mm to obtain samples for glass transition point (Tg), water absorption rate and moisture absorption rate.

Using the above samples, the heat resistance to moisture absorption, glass transition point (Tg), water absorption rate and moisture absorption rate of the laminate were measured and are shown in Table 1.

Comparative Example 1 A reactive brominated compound which is a reactive flame retardant having an unsaturated bond in place of decabromodiphenylethane in Example 1 is represented by the following general formula [5]. In the same manner as in Example 1 except that 35 parts by weight of N- (2,4,6-tribromophenyl) maleimide (manufactured by Mitsui Toatsu Fine Co., Ltd .: trade name TBP-MI, 58.5 Br%) was used. A PPO resin composition, a prepreg and a laminated board were obtained by measuring the moisture absorption heat resistance, the glass transition point (Tg), the water absorption rate and the moisture absorption rate of the laminated board, and the results are shown in Table 1.

[0039]

[Chemical 7]

(Comparative Example 2) In Example 1, instead of decabromodiphenylethane, an addition type flame retardant represented by the following general formula [6] which is a dissolution type flame retardant soluble in the solvent (trichloroethylene) is used. Fuel (Nissan Chemical Co., Ltd .:
A PPO resin composition, a prepreg and a laminated plate were obtained in the same manner as in Example 1 except that 29.1 parts by weight of the product name SR-245, 67.4 Br%) was used, and the laminated plate had a moisture absorption heat resistance and a glass. The transition point (Tg), water absorption rate and moisture absorption rate were measured and are shown in Table 1.

[0041]

Embedded image

The glass transition point (Tg) of the PPO resin composition was determined using TMA according to the thermodynamic analysis method of IPC-TM-650, 2.4.24.

Moisture absorption heat resistance was 50 mm × 50 m as obtained.
m, double-sided copper clad laminate is boiled at 100 ° C for 2 hours D-
Performed by pressure cooker test (PCT) at 2/100 and 135 ° C, 2 atm for 2 hours, and visually inspected for blister after dipping in a solder bath at 260 ° C for 20 seconds with 5 samples each. I observed. For example, 5
For those that did not have blisters, 0/5,
5 / out of 5 out of 5 out of 5
Indicated as 5 and shown in Table 1.

The water absorption rate is in accordance with JIS-C6481.
It was measured at E-24 / 50 + D-24 / 23. That is, the water absorption was measured by drying at 50 ° C. for 24 hours and immersing in water at 23 ° C. for 24 hours. Moisture absorption rate is E
It was measured at -24 / 50 + C-24 / 60/95. That is, by drying at 50 ° C. for 24 hours, conditioning at 23 ° C. for 24 hours, relative humidity 95%, and 60 ° C. for 24 hours,
The moisture absorption rate was measured. The sample used for measuring the water absorption rate and the moisture absorption rate was 5 after etching the surface copper foil of the obtained laminated plate.
The one cut into 0 mm × 50 mm was used.

[0045]

[Table 1]

From Table 1, in Example 1, the glass transition point of the obtained PPO resin composition is higher than that of Comparative Examples 1 and 2, and in addition, water resistance, moisture resistance and moisture absorption heat resistance of the laminated plate are high. It was confirmed that the property was good.

[0047]

According to the PPO resin composition according to the first aspect of the present invention, the flame retardant is a brominated organic compound that does not react with PPO and TAIC, and is not soluble in the solvent.
Since it is dispersed, thermoplastic PPO and thermosetting TA
When mixed with IC and cured, an interpenetrating network structure [I
PN (Interpenetrating Polymer Net Work) is formed, and it has an extremely excellent structure as a laminated plate with high heat resistance, so a prepreg and laminated plate with a high glass transition point, water resistance, moisture resistance, moisture absorption heat resistance can get.

According to the PPO resin composition according to the second aspect of the present invention, the flame retardant is unlikely to settle in the varnish of the PPO resin composition, and even when the substrate is impregnated, the flame retardant is uniform. Since varnish can be obtained, workability is improved.

According to the PPO resin composition of claim 3 of the present invention, since the brominated organic compound is decabromodiphenylethane or 4,4-dibromobiphenyl,
The prepreg and laminated plate having a high glass transition point and excellent water resistance, moisture resistance, and moisture absorption heat resistance because TAIC is almost completely cured to form a good IPN without inhibiting the formation of IPN of PO-TAIC. Is obtained.

According to the PPO resin composition of claim 4 of the present invention, 30 to 60 parts by weight of PPO and 35 parts of TAIC are used.
To 62 parts by weight and the brominated organic compound in a proportion of 8 to 20 parts by weight, a prepreg having a high glass transition point, flame retardancy, heat resistance and water resistance, moisture resistance, and moisture absorption heat resistance. A laminate is obtained.

According to the prepreg according to claim 5 of the present invention, a substrate is impregnated with the PPO resin composition according to any one of claims 1 to 4, and the material is heated and dried to be semi-cured.
It is possible to obtain a prepreg used for a laminated plate which is excellent in water resistance, moisture resistance, and moisture absorption heat resistance.

According to the laminated plate of the sixth aspect of the present invention, a predetermined number of the prepregs of the fifth aspect are heated and pressed for lamination molding, so that the laminated plate is excellent in water resistance, moisture resistance and moisture absorption heat resistance. Is obtained.

Claims (6)

[Claims] 1. A varnish obtained by adding a solvent to a polyphenylene oxide resin composition containing polyphenylene oxide, triallyl isocyanurate, a compatibilizer and a flame retardant, wherein the flame retardant is polyphenylene oxide and triallyl isocyanurate. A polyphenylene oxide resin composition, which is a non-reacted brominated organic compound and is not dissolved in the solvent but dispersed therein. 2. The true specific gravity of the brominated organic compound is 3.0.
The polyphenylene oxide resin composition according to claim 1, wherein: 3. The brominated organic compound is decabromodiphenylethane represented by the following general formula [1] or 4,4-dibromobiphenyl represented by the following general formula [2]. The polyphenylene oxide resin composition according to claim 1 or 2. Embedded image Embedded image 4. Polyphenylene oxide in an amount of 30-60
By weight, containing 35 to 62 parts by weight of triallyl isocyanurate, and containing the brominated organic compound having a bromine content of 8 to 20% by weight with respect to the total amount of the polyphenylene oxide resin composition. The polyphenylene oxide resin composition according to any one of claims 1 to 3, wherein 5. A prepreg obtained by impregnating a substrate with the polyphenylene oxide resin composition according to any one of claims 1 to 4, heat-drying and semi-curing. 6. A laminated plate formed by laminating and molding a predetermined number of the prepreg according to claim 5 by heating and pressing.