JP2003034731A - Method of manufacturing prepreg - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a prepreg obtained by impregnating a glass cloth with resin and used for a printed wiring board which is excellent in printed wiring board characteristics, has little resin-free spaces and can be manufactured without using an organic solvent harmful to the environment. SOLUTION: This method of manufacturing a prepreg uses a resin varnish obtained by dispersing (a) granular polyphenylene ether and (b) a thermocurable component in water to obtain a prepreg for a printed wiring board excellent in characteristics. Since the main solvent is water, the varnish causes no pollution in a work environment through the whole process from the preparation to the application and the drying and is effective in the environment conservation and the global environment protection.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a glass cloth resin-impregnated prepreg (hereinafter referred to as prepreg) for a glass cloth reinforced resin laminate, which is particularly used for printed wiring boards. More specifically, the present invention improves reliability, heat resistance, and electrical characteristics by blending polyphenylene ether and / or modified polyphenylene ether having excellent reliability, heat resistance, and electrical characteristics with a thermosetting resin component. Excellent printed wiring boards can be manufactured, and most of the solvent of the resin varnish used during manufacturing is water, so it is effective in protecting the global environment and improving the working environment. Use a resin varnish with low viscosity at room temperature Therefore, a method of manufacturing a prepreg having excellent productivity is provided.

[0002]

2. Description of the Related Art Conventionally, a glass cloth reinforced resin laminated board processed into a printed wiring board or the like uses a resin solution prepared by dissolving a thermosetting resin such as an epoxy resin or a polyimide resin as a matrix resin in an organic solvent. (Hereinafter, resin varnish) is impregnated into a glass cloth, and the organic solvent is heated and dried to produce a glass cloth resin-impregnated prepreg (hereinafter referred to as prepreg) in which the resin is in a semi-cured (B stage) state. Alternatively, it is manufactured by a method of obtaining a glass cloth reinforced resin laminated plate (hereinafter referred to as a laminated plate) by laminating a plurality of sheets, performing heating and pressure molding, and curing the resin.

However, in recent years, the characteristics required for printed wiring boards have become more advanced, and in particular, the conventional epoxy resin laminates satisfy the required characteristics in terms of electrical characteristics, heat resistance, reliability and moisture absorption resistance. Is difficult. Also,
From the viewpoint of protecting the global environment and improving the working environment of the manufacturing process, it is desired to reduce the amount of organic solvent used, but at room temperature solid or high-viscosity epoxy resin can be used without dilution with an organic solvent.
It is difficult to coat and impregnate glass cloth.

Therefore, in order to improve the characteristics of the printed wiring board, a thermoplastic high-performance engineering resin such as polyphenylene ether or modified polyphenylene ether is used in combination with a thermosetting resin such as an epoxy resin to form a matrix resin and a method (special Hei 6-17442, Japanese Patent Publication No. 64-64
3223) has been tried. However, thermoplastic high-performance engineering resins such as polyphenylene ether have excellent characteristics and chemical resistance, but have drawbacks such as being difficult to dissolve in an organic solvent and having a very high viscosity. In the case of polyphenylene ether, it dissolves only in a chlorine-based solvent or an aromatic organic solvent such as toluene or xylene when heated at 50 ° C or higher, which deteriorates the working environment during prepreg production, heats the resin varnish, and uses energy by heat retention. From the viewpoints of protecting the global environment in the manufacturing process and improving the working environment in the manufacturing process, it is not preferable to the conventional epoxy resin prepreg manufacturing. In addition, since the resin varnish has a high viscosity, the impregnating property of the resin into the glass cloth is poor, and an unimpregnated portion of the resin occurs in the yarn bundle of the glass cloth in the prepreg state, which causes a high pressure in the laminated plate forming process. Need high heat ,.

Further, from the viewpoint of protecting the global environment and improving the working environment, a method of producing a prepreg by heating and melting an epoxy resin without applying a solvent, coating, impregnating and heating a glass cloth (JP-A-11- No. 302401), and a method of reducing the use of an organic solvent by using water as a solvent for a resin varnish using an epoxy resin or the like as a water-dispersed emulsion (JP-A-9-
No. 291161, JP-A-9-316219).
Etc. have been tried. However, it is difficult to meet the required characteristics of recent printed circuit boards by using these thermosetting resins as matrix resins.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems. That is, it is an object of the present invention to provide a method for producing a prepreg, which has excellent printed circuit board characteristics, has a small amount of resin-unimpregnated portion, and can be produced without using an organic solvent that adversely affects the environment.

[0007]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that (a) particulate polyphenylene ether and / or modified polyphenylene ether, and (b) thermosetting property. It was found that by using the component as a resin varnish (c) dispersed in water, it is possible to produce a prepreg which is excellent in printed circuit board characteristics, has a small amount of resin unimpregnated portion, and does not use an organic solvent that adversely affects the environment. The present invention has been completed. That is, the present invention is: (1) A method for producing a prepreg by coating and impregnating a glass cloth with a resin varnish, followed by heating and drying, wherein (a) a polyphenylene ether having a particle diameter of 106 μm or less and / or
Alternatively, a resin varnish containing a modified polyphenylene ether, (b) a thermosetting monomer and / or a thermosetting polymer as a thermosetting component, and (c) a solvent containing 90% by weight or more of water is used. (2) (b) the thermosetting component contains triallyl isocyanurate and / or triallyl cyanurate and a diallyl phthalate monomer (1).
The prepreg manufacturing method described above, (3) resin varnish,
(A) contains a polyphenylene ether and / or modified polyphenylene ether having a particle size of 106 μm or less in the state of an emulsion and / or dispersion dispersed by a surfactant containing a polymer type surfactant,
(B) A method for producing a prepreg according to (1) or (2), which comprises a thermosetting component dispersed in a reactive surfactant having an unsaturated double bond.
(4) The method for producing a prepreg according to any one of (1) to (3), which comprises heating the glass cloth to 130 ° C. or higher and 180 ° C. or lower in a heating step after impregnating the glass cloth with the resin varnish. Is.

The present invention will be described in detail below. (A) Polyphenylene ether The polyphenylene ether referred to in the present invention is a polyphenylene ether represented by the following general formula (1) or a modified polyphenylene ether represented by the following general formula (2), having a particle diameter of 106 μm or less. If there is, it is not particularly limited.

[0009]

[Chemical 1]

[0010]

[Chemical 2] Here, R in the general formula (2) is a group for imparting compatibility with the thermosetting component and cross-linking property, such as an allyl group, a maleic anhydride group, an epoxy group, a propargyl group, and an amino group. It is an organic functional group and may be a group to which these groups are added.

The particle diameter of the polyphenylene ether and / or the modified polyphenylene ether (hereinafter, the two are collectively referred to as polyphenylene ether) is 106 μm or less, preferably 62 μm or less. The particle size here is 106μ
m or less means the opening of the JIS standard sieve is 106 μm
It means that the particle size passes through the No. 4 sieve. The average diameter is not particularly limited and is 0.01 μm or more and 20 μm or more from the viewpoint of the dispersibility of particles in the resin varnish.
m or less, and preferably 0.02 μm or more and 10 μm or less. If the particle size is larger than 106 μm, the glass cloth may be impregnated with the resin varnish and then dried and heated.
Since the compatibility with the thermosetting component is lowered and the prepreg surface is likely to have irregularities and the glass cloth is not impregnated with the resin, the particle diameter is required to be 106 μm or less.
The method for adjusting the particle size to 106 μm or less includes a particle sieving method, a wet or dry classification method, and the like.
A method of removing particles larger than m, a method of performing mechanical granulation such as pulverization, and a method of obtaining a submicron particle dispersion by dissolving in a soluble solvent and then adding an insoluble solvent to emulsify or suspend Alternatively, it can be obtained by any method such as a method of removing a solvent component from the dispersion liquid to obtain a fine powder.

(B) Thermosetting Component The thermosetting component is not particularly limited as long as it is a resin such as an epoxy resin, an unsaturated polyester resin or a diallyl phthalate prepolymer, or a thermosetting monomer. . The glass transition temperature of the cured product of the thermosetting component is preferably 110 ° C or higher and 300 ° C or lower, and more preferably 130 ° C or higher and 280 ° C or lower. The glass transition temperature of the resin means that the content of the resin is 35.
RD of 0-45.0% by weight glass cloth reinforced laminate
It means the temperature at which the peak of tan δ whose viscoelastic behavior was measured by AII (Rheometrics Co., Ltd.). A resin having a glass transition temperature of less than 110 ° C causes deterioration in heat resistance to moisture absorption and electrolytic corrosion, which are basic performances of a resin printed circuit board using a glass cloth, so that the glass transition temperature of the thermosetting component is 110 ° C or higher. It is preferable. Further, when the glass transition temperature is 300 ° C. or higher, the resin becomes hard and brittle, so that the adhesiveness with glass is deteriorated, and the machine such as drilling, punching hole processing and cutting with a cutter at the time of printed circuit board processing is used. The glass transition temperature is 30 because the phenomenon of peeling between glass and resin easily occurs due to mechanical stress.
It is preferably 0 ° C. or lower.

The epoxy resin is generally a compound having an epoxy group (hereinafter referred to as a main agent) and a compound having a functional group capable of addition reaction with an epoxy group (hereinafter referred to as a curing agent).
And a curing catalyst that accelerates the polymerization of the epoxy group and the reaction between the main agent and the curing agent. As the main agent, a compound using bisphenol A represented by the following general formula (3) and / or tetrabromobisphenol A as a raw material,

[Chemical 3]

Compounds using polyfunctional phenols represented by the following general formulas (4) and (5) as a raw material,

[Chemical 4]

[0015]

[Chemical 5]

Further, the following general formulas (6), (7), (8)
Compound shown by

[Chemical 6]

[0017]

[Chemical 7]

[0018]

[Chemical 8] And the like, and these epoxy resins may be modified to have a water-dispersible structure.

Examples of the curing agent include dicyandiamide, amine compounds, phenol novolac resins, organic acid compounds and blocked isocyanate compounds. Examples of the curing catalyst include imidazole compounds, organic phosphorus compounds, Lewis acid salts, tertiary amine compounds and the like. According to the present invention, a prepreg for a printed wiring board has a high adhesiveness peculiar to an epoxy resin, a storage stability of a prepreg, and electrical characteristics, heat resistance, reliability and low hygroscopicity peculiar to polyphenylene ether. Also,
In order to obtain further improved electrical characteristics, heat resistance, and low hygroscopicity, it is preferable to use a thermosetting component which is cured by a polymerization curing reaction of an allyl group (hereinafter referred to as an allyl polymerization thermosetting component) as a thermosetting component. . As the allyl polymerization thermosetting component, triallyl isocyanate represented by the following general formula (9),

[0020]

[Chemical 9]

Triallyl cyanurate represented by the following general formula (10),

[Chemical 10]

A diallyl compound of phthalic acid represented by the following general formula (11),

[Chemical 11] Is exemplified, and a prepolymer of diallyl phthalate can also be used.

Examples of the catalyst for curing the allylic compound include organic peroxides, cobalt organic compounds, metal soaps and the like. In particular, triallyl isocyanate and triallyl cyanurate are excellent in compatibility with polyphenylene ether, and the heat resistance and electric characteristics of the cured product are improved, so that they are preferably used as thermosetting components. When triallyl isocyanate and triallyl cyanurate are used as thermosetting components, when the prepreg is heated and pressure-molded to produce a laminate, the fluidity of the prepolymer stage at the time of polymerization and curing is poor. It is more preferable to add a diallyl compound, and the addition amount thereof is preferably 2 parts by weight or more and 50 parts by weight or less, and 5 parts by weight or more and 40 parts by weight or less, based on 100 parts by weight of triallyl isocyanurate and / or triallyl cyanurate. It is more preferable if It is also possible to use an epoxy resin and an allyl polymerization thermosetting component together.

(C) Blending Ratio of Polyphenylene Ether and Thermosetting Component The blending ratio of the polyphenylene ether and the thermosetting component is not particularly limited, but it is thermosetting with respect to 100 parts by weight of polyphenylene ether. Over 50 parts by weight of ingredient 9
The amount is preferably 00 parts by weight or less, more preferably 75 parts by weight or more and 500 parts by weight or less. When the amount of the thermosetting component is less than 50 parts by weight, it is not preferable because the resin layer is not formed in the prepreg state and the surface layer resin is easily peeled off. When it exceeds 900 parts by weight, the effect of improving the characteristics of polyphenylene ether is small and the performance of the printed wiring board is poor. The improvement is insufficient, which is not preferable.

(D) Resin varnish The resin varnish referred to here is a resin varnish, which is used to impregnate a yarn bundle of glass cloth with a matrix resin (hereinafter referred to as a resin), in order to reduce the viscosity of the resin, and to dry the prepreg.
It refers to a mixed liquid of a resin and a solvent in which a solvent that is dried and removed during curing is mixed with a resin. The resin varnish in the present invention needs to be a resin varnish containing 90% by weight or more of water as the solvent composition, and more preferably 95% by weight or more of water. The solvent composition of 90% by weight or more of water means that 90% by weight or more of the solvent in the resin varnish is water. When the solvent composition is 90% by weight or less of water, the polyphenylene ether and a part of the thermosetting component are dissolved in the solvent, causing a decrease in water dispersion stability of the resin component in the resin varnish and an increase in the viscosity of the resin varnish. It is necessary that the composition is a resin varnish containing 90% by weight or more of water.

When the solvent composition of the resin varnish is 90% by weight or more of water, the polyphenylene ether and the thermosetting component are present in the solvent in the form of particles in the state of emulsion, suspension and / or dispersion. The viscosity increase is lower than that of the resin varnish dissolved in the solvent, and it is not necessary to heat the resin varnish. Furthermore, the use of water as the solvent is different from the thermosetting resin dissolved or dispersed in the organic solvent, because the exhaust gas in the drying and heating steps during the prepreg production is only water vapor, so the release of the organic solvent into the atmosphere is different. This eliminates the adverse effects on the global environment, the risk of chronic and acute poisoning due to an increase in the concentration of organic solvents in the working environment, and the risk of explosion due to flammable organic solvents. In addition, large-scale facilities such as an explosion-proof device and an organic solvent recovery device for reducing the adverse effects and dangers of the organic solvent are not required.

Water that can be used in the present invention includes tap water,
Distilled water, ion-exchanged water, soft water or hard water can be used. As a method for producing a resin varnish, a method of producing an aqueous dispersion of each of polyphenylene ether and a thermosetting component and mixing them to obtain a resin varnish can be used. As a method for water-dispersing polyphenylene ether, a method of dispersing powdery polyphenylene ether in water with a surfactant or the like, after dissolving in a soluble solvent, and emulsified water dispersion using a surfactant together with the solvent, the final Any method of removing the solvent so that the solvent composition can be adjusted to 90% by weight or more of water in the state of the resin varnish of above.

When the powdery polyphenylene ether is dispersed in water, it is preferable to add a polymer type surfactant. The high-molecular-weight surfactant referred to here is one having a polymer structure of a monomer having surface-active ability, and is a formalin condensate of naphthalene sulfonate represented by the following general formula (12),

[Chemical 12]

A polystyrene sulfonate represented by the following general formula (13):

[Chemical 13]

A polyacrylic acid salt represented by the following general formula (14),

[Chemical 14]

A salt of a copolymer of a vinyl compound represented by the following general formula (15) and a carboxylic acid monomer,

[Chemical 15]

A polyacrylic acid partial alkyl ester represented by the following general formula (16):

[Chemical 16] Etc. are exemplified.

By using the high molecular type surfactant, the surfactant is adsorbed on the surface of the polyphenylene ether particles,
Due to the protective colloid effect and electric charge, a highly dispersed and stable aqueous dispersion can be obtained. The addition amount of the polymer surfactant is preferably 0.1 parts by weight or more and 5.0 parts by weight or less, more preferably 0.2 parts by weight or more and 3.0 parts by weight or less with respect to 100 parts by weight of polyphenylene ether. . When the amount is less than 0.1 parts by weight, the effect of coating the surface of the particles is small and the dispersibility is lowered, which is not preferable. When the amount is more than 5.0 parts by weight, the characteristics of the printed wiring board are deteriorated and the polymer surfactant is used. It is not preferable because the viscosity of the resin varnish increases due to an excessive amount of. In addition, many polymeric surfactants are generally anionic, but from the viewpoint of reliability, electrical characteristics, and moisture absorption resistance of printed wiring boards, organic salts such as ammonium salts are preferable to inorganic salts such as sodium salts. preferable.

Further, addition of a monomer type surfactant and a wetting agent for the purpose of promoting adsorption of the polymer surfactant to the polyphenylene ether particles and improving the stability of the water dispersion also suppresses foaming of the water dispersion. It is also possible to add an antifoaming agent for this purpose. These monomer type surfactants, wetting agents, and defoaming agents also affect the characteristics of the printed wiring board, so it is preferable to use an ammonium salt type anionic compound or nonionic compound. As a water dispersion means of powdery polyphenylene ether, a polymer surfactant in water, a monomer type surfactant, a wetting agent,
After adding, dispersing and dissolving an antifoaming agent, a method of adding polyphenylene ether powder and forcibly dispersing with a device such as a homogenizer, a ball mill, a mixer or the like that can stir with a high shear is possible.

After dissolving the polyphenylene ether in a soluble solvent, a surfactant is used together with the solvent to emulsify and disperse the solvent, and the solvent is removed so that the solvent composition can be adjusted to 90% by weight or more of water in the final resin varnish. If you want to
After dissolving polyphenylene ether in a soluble solvent, monomer type surfactant, wetting agent, defoaming agent are added, and water is added to forcefully disperse with a homogenizer, ball mill, mixer, etc. Can be added. The solvent can be removed by a method of forcibly removing the solvent by heating and / or vacuum suction. It is also possible to add a thickener or the like to prevent the particles of the polyphenylene ether aqueous dispersion from settling.
As the water-dispersion method of the thermosetting component, a method in which a surfactant is added to the melted thermosetting component, and water is added to forcibly disperse with a device such as a homogenizer, a ball mill or a mixer, a thermosetting component It is possible to disperse emulsified water with a solvent using a surfactant and remove the solvent so that the solvent composition can be adjusted to 90% by weight or more of water in the final resin varnish.

As the surfactant to be used, a monomer type surfactant having a strong emulsifying power is effective, and a surfactant suitable for the thermosetting component to be used is selected. It is preferably 20 parts by weight or less with respect to 100 parts by weight of the curable resin. Further, in order to maintain the characteristics of the printed wiring board, it is preferable to use an ammonium salt type anionic compound or nonionic compound. Since the monomer-type surfactant is likely to have adverse effects such as moisture absorption acceleration of the resin when it remains in the monomer state in the resin, it reacts with the thermosetting component in the prepreg drying, heating step, and laminate heat-pressing step. Preferred are reactive surfactants that self-polymerize. In particular, it is preferable to use a reactive surfactant having an unsaturated double bond for the allyl polymerization thermosetting component. As the surfactant having an unsaturated double bond, any surfactant having an unsaturated double bond and having a surfactant ability can be used and is represented by the following general formula (17). Sulfate ester salt of polyoxyethylene allyl glycidyl nonyl phenyl ether,

[0037]

[Chemical 17]

Polyoxyethylene allyl glycidyl nonyl phenyl ether represented by the following general formula (18),

[Chemical 18]

Polyoxyethylene nonylpropenyl phenyl ether represented by the following general formula (19),

[Chemical 19]

Polyoxyethylene nonylpropenyl phenyl ether sulfate ester salt represented by the following general formula (20),

[Chemical 20]

An acrylic or methacrylic modified product of polyoxyethylene nonylphenyl ether represented by the following general formula (21),

[Chemical 21] Etc. are exemplified.

Further, a polymer type surfactant and a wetting agent may be added for the purpose of improving the stability of the aqueous dispersion of the thermosetting component, and an antifoaming agent for suppressing foaming of the aqueous dispersion may be added. It is also possible to add. It is also possible to use a self-emulsifying modified epoxy resin or a water-soluble epoxy resin as the thermosetting component, or to use it together to obtain an aqueous dispersion without using a surfactant. Further, both the polyphenylene ether and the thermosetting component are dissolved in a solvent, or after being melt-compatibilized by heating, as in the method of dispersing the mixture in water, the polyphenylene ether and the thermosetting component are previously compatibilized. A method of water dispersion is also possible. However, also in this case, the particle diameter of the aqueous dispersion of the polyphenylene ether and the thermosetting component needs to be 106 μm or less.

(E) Other Compounds It is also possible to add a thermoplastic resin other than polyphenylene ether to compensate for the brittleness of the resin. Also, in order to impart flame retardancy, bromine-containing organic matter, chlorine-containing organic matter,
It is also possible to add an organic compound that imparts flame retardancy such as a phosphorus-containing organic substance, and a metal oxide, a hydrate of a metal oxide, or an inorganic compound that imparts flame retardancy such as phosphorus. Further, powders such as metal oxides and organic compounds may be mixed in order to improve the strength and elastic modulus of the laminated plate.

If these other compounds are powders,
The particle size is preferably 106 μm or less like the polyphenylene ether, and it is preferable to use a surfactant containing a polymer surfactant for the water dispersion. Also,
A method in which a surfactant is added to the other compound that has been melted, and water is added to forcibly disperse using a device such as a homogenizer, a ball mill, and a mixer, and the other compound is dispersed in an emulsified water using a surfactant together with a solvent. It is possible to remove the solvent so that the solvent composition can be adjusted to 90% by weight or more of water in the final resin varnish. The concentration of the polyphenylene ether in the resin varnish, the thermosetting component, and the total amount of the other components (hereinafter referred to as solid content) is not particularly limited, and the solid content concentration is preferably 20% by weight or more and 80% by weight or less, It is more preferably 30% by weight or more and 70% by weight or less. The viscosity of the resin varnish at 25 ° C. is preferably 20 to 2000 Pa · s, and 30 to 100
0 Pa · s is more preferable.

(F) Manufacture of prepreg In the prepreg of the present invention, any method can be applied as a method of impregnating and coating a glass cloth with a resin varnish. (A) The resin varnish is stored in a bath to form a glass cloth. After passing the glass cloth with a slit, a predetermined amount of resin varnish is impregnated with the slit, and the excess resin varnish is scraped off with the slit or the mangle so that (a) roll coater, die coater, gravure coater, etc. It is possible to directly impregnate the cloth with a predetermined amount of the resin varnish and apply it. Further, as a method of heating and drying the solvent and / or semi-curing the resin after impregnating the glass cloth with the resin varnish, known methods such as hot air and electromagnetic waves can be used. Alternatively, the method of semi-curing the resin, the method of semi-curing the resin with ultraviolet rays or electron beams after drying the solvent by heating, and the like are not particularly limited.

The temperature at which the prepreg is heated and dried is not particularly limited, but in order to sufficiently promote the compatibility of the polyphenylene ether and the thermosetting component, it is preferable to heat it to 130 ° C. or higher, and 140 ° C. The above is more preferable. Further, in order to suppress the thermal stability of the thermosetting component and the evaporation, volatilization and decomposition of the curing agent, the heating temperature upper limit is 180.
The heating time is preferably 30 ° C. or more and less than 20 minutes, and more preferably 1 minute or more and less than 15 minutes. Further, the content of glass cloth in the prepreg in the state of prepreg (hereinafter, referred to as glass content) is at least 80% or less, preferably 75% or less. The lower limit is limited from the viewpoint of dimensional stability of the laminated plate, and usually 20% or more is preferable. When the glass content of the prepreg exceeds 80%, the prepreg has a resin only in the yarn bundle portion of the glass fiber woven fabric, which makes it impossible to form a laminated plate.

When the glass cloth is subjected to pretreatment such as corona discharge treatment and plasma discharge treatment before impregnating the glass cloth with the resin varnish, the glass surface is activated and the resin varnish inside the yarn bundle of the glass cloth is activated. Permeation is improved, and as a result, a prepreg having less resin-impregnated portion is obtained. For example, in the case of corona discharge treatment, the applied power is 0.1
-40.0 kW, preferably 0.3-20.0 kW, frequency 1-120 kHz, preferably 5-50 kHz,
The processing time is preferably 0.05 seconds or longer, more preferably 0.1 seconds or longer. Further, in order to improve the surface smoothness of the prepreg, the prepreg may be heated and pressed by roll compression or the like. In the case of processing with a heating roll, the lower limit of the heating roll temperature is preferably 70 ° C or higher, and more preferably 90 ° C or higher, in which the resin has flexibility for flattening under pressure. Further, the upper limit is preferably 200 ° C. or lower in consideration of heat deterioration of the resin and progress of curing of the thermosetting component, and 170 ° C.
The following is more preferable.

(G) Glass Cloth The glass cloth applied to the present invention may be any glass cloth such as E glass, A glass, D glass and S glass. As a glass cloth, weave density is 10
200/25 mm, preferably 15-100 / 25
mm and the mass is 5 to 400 g / m ² , preferably 1
The weaving method is 0 to 300 g / m ² , and a weave method such as a plain weave, a satin weave, a twill weave, and a Nanako weave can be used. Alternatively, a glass cloth woven from glass threads that are textured on both sides or on the other hand may be used. Further, a glass cloth at the stage where the sizing agent necessary for weaving is attached, a glass cloth at the stage where the sizing agent is removed, or a glass cloth at which the silane coupling agent has already been treated by a known surface treatment method. Any of Further, it may be a glass cloth which has been subjected to physical processing such as opening by a columnar flow or a water flow by a high frequency vibration method.

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples.

[Example 1] (Preparation of polyphenylene ether aqueous dispersion)
A JIS standard sieve was added to a solvent prepared by adding 1.0 part by weight of a polymeric surfactant (Discoat N-14 (registered trademark) manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) to 99 parts by weight of distilled water. Powdered polyphenylene ether (number average molecular weight: 7 with a mesh size of 106 μm and particles not passing through 106 μm removed)
000, hereinafter referred to as PPE) 100 parts by weight,
The mixture was stirred with a homogenizer to obtain an aqueous dispersion of polyphenylene ether.

(Preparation of Aqueous Dispersion of Thermosetting Component) Methyl ethyl ketone (hereinafter referred to as MEK) solution of low brominated epoxy resin (Epicoat 5046B80 (registered trademark) manufactured by Yuka Shell Epoxy Co., Ltd.): 80 parts by weight of resin component Part, ortho-cresol novolac type epoxy resin (Epicoat 1
80S70B75 (registered trademark) manufactured by Yuka Shell Epoxy Co., Ltd .: 20 parts by weight of resin is mixed, and then MEK
Was removed by heating under vacuum, and polyoxyethylene nonylphenyl ether having a HLB value of 19 (Neugen EA-170 (registered trademark) Daiichi Kogyo Seiyaku Co., Ltd.) was heated at 80 ° C.
)): 1.0 part by weight, polyoxyethylene nonylphenyl ether having an HLB value of 12 (Neugen EA-120).
(Registered trademark) manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.): 1.0 part by weight, polyoxyethylene nonylphenyl ether having an HLB value of 6 (Neugen EA-50 (registered trademark) Dai-ichi Kogyo Seiyaku Co., Ltd.) ): 1.0 part by weight was added, and 97 parts by weight of distilled water was added while forcibly stirring to obtain an aqueous dispersion of a thermosetting component.

(Preparation of resin varnish) An aqueous dispersion of polyphenylene ether: 100 parts by weight and an aqueous dispersion of a thermosetting component: 100 parts by weight were mixed, and dicyandiamide (JIS standard) was used as a curing agent for the thermosetting component. Of dicyandiamide which passed through a 38 μ sieve and used a 38 μ sieve.): 2.5 parts by weight, 2-ethyl-4-methylimidazole (hereinafter referred to as 2E4MZ) as a curing catalyst: 0.1 parts by weight Parts were added to obtain a resin varnish of the present invention. (Glass cloth) 2116 / AS891AW (manufactured by Asahi Schwabel Co., Ltd.) surface-treated with a special aminosilane coupling agent was used. (Preparation of prepreg) After the resin varnish was stored in a bath and passed through a glass cloth, the excess resin varnish was scraped off with a slit having a gap of 0.35 mm and dried at 170 ° C for 3 minutes, and the prepreg using the resin varnish of the present invention was used. Got

[0052]

[Example 2] (Preparation of polyphenylene ether aqueous dispersion)
By the same method as in Example 1, an aqueous dispersion of polyphenylene ether was obtained. (Preparation of Aqueous Dispersion of Thermosetting Component) Triallyl isocyanate (TAIC (registered trademark) manufactured by Nippon Kasei Co., Ltd.): 80
Parts by weight and diallyl terephthalate (Daiso Co., Ltd.)
Made): 20 parts by weight and 1,4 (or1, as a curing catalyst)
3) -bis ((t-butyldioxy) isopropyl) benzene (Perbutyl P (registered trademark) NOF CORPORATION)
Manufactured): 10 parts by weight, HLB value 17.9 as a surfactant
Polyoxyethylene nonylpropenyl phenyl ether (Aqualon RN-50 (registered trademark) manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.): 5.0 parts by weight are mixed, and 95 parts by weight of distilled water is added while forcibly stirring. An aqueous dispersion of the thermosetting component was obtained.

(Preparation of resin varnish) Aqueous dispersion of polyphenylene ether: 100 parts by weight of decabromodiphenylethane as a flame retardant (screened with a JIS standard mesh 38 μ sieve and powder passing through 38 μ sieve was used. :): 2
After adding 0 part by weight and forcibly stirring, 100 parts by weight of an aqueous dispersion of a thermosetting component was mixed to obtain a resin varnish of the present invention. (Glass cloth) 2116 / AS760AW surface-treated with silane coupling agent for special radical polymerization
(Asahi Schebel Co., Ltd.) was used. (Preparation of prepreg) The resin varnish was stored in a bath, passed through a glass cloth, the excess resin varnish was scraped off with a slit having a gap of 0.35 mm, and the resin varnish of the present invention was dried for 3 minutes at 150 ° C. Got

[0054]

[Example 3] (Preparation of polyphenylene ether aqueous dispersion)
By the same method as in Example 1, an aqueous dispersion of polyphenylene ether was obtained. (Preparation of Aqueous Dispersion of Thermosetting Component) Tetrafunctional Glycidylamine Epoxy Resin (Epicoat 6
04 (registered trademark) Yuka Shell Epoxy Co., Ltd .: 50
MEK solution of ortho-cresol novolac type epoxy resin (Epicoat 180S70B75 (registered trademark) Yuka Shell Epoxy Co., Ltd.): 50 parts by weight of resin is mixed, MEK is heated under vacuum and removed at 80 ° C. While heating, polyoxyethylene nonylpropenyl phenyl ether having a HLB value of 17.9 as a surfactant (Aqualon RN-50 (registered trademark) Daiichi Kogyo Seiyaku Co., Ltd.)
(Manufactured): 5.0 parts by weight were mixed, and 97 parts by weight of distilled water was added while forcibly stirring to obtain an aqueous dispersion of thermosetting components.

(Preparation of resin varnish) Aqueous dispersion of polyphenylene ether: 100 parts by weight of decabromodiphenylethane as a flame retardant (sieve through a sieve having a JIS standard opening of 38μ, and powder passing through a 38μ sieve was used. :): 2
After adding 0 parts by weight and forcibly stirring, 100 parts by weight of an aqueous dispersion of a thermosetting component was mixed, and dicyandiamide as a curing agent for the thermosetting component (sieving with a 38 μ sieve according to JIS standard, 38 μ Dicyandiamide which passed through a sieve of (4) was used.): 4.5 parts by weight, 2-ethyl-4-methylimidazole (hereinafter 2E4MZ) as a curing catalyst: 0.1
Parts by weight were added to obtain a resin varnish of the present invention. (Glass cloth) 2116 / AS891AW (manufactured by Asahi Schwabel Co., Ltd.) surface-treated with a special aminosilane coupling agent was used. (Preparation of prepreg) After the resin varnish was stored in a bath and passed through a glass cloth, the excess resin varnish was scraped off with a slit having a gap of 0.35 mm and dried at 170 ° C for 3 minutes, and the prepreg using the resin varnish of the present invention was used. Got

[0056]

[Example 4] (Preparation of polyphenylene ether aqueous dispersion)
By the same method as in Example 1, an aqueous dispersion of polyphenylene ether was obtained. (Preparation of aqueous dispersion of thermosetting component) Triallyl isocyanate (TAIC (registered trademark) manufactured by Nippon Kasei Co., Ltd.): 50
Parts by weight and 1,4 (or1,3) -bis ((t-butyldioxy) isopropyl) benzene (Perbutyl P (registered trademark) manufactured by NOF CORPORATION) as a curing catalyst: 10 parts by weight, orthocresol novolac type epoxy MEK removal resin of resin (Epicoat 180S70B75 (registered trademark) Yuka Shell Epoxy Co., Ltd.): 50 parts by weight was mixed and then heated at 70 ° C., and HLB was added as a surfactant.
Polyoxyethylene nonylpropenyl phenyl ether having a value of 17.9 (Aqualon RN-50 (registered trademark) manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.): 5.0 parts by weight were mixed, and 95 parts by weight of distilled water were mixed under forced stirring. Was added to obtain an aqueous dispersion of thermosetting component.

(Preparation of Resin Varnish) Aqueous dispersion of polyphenylene ether: 100 parts by weight of decabromodiphenylethane as a flame retardant (sieving with a sieve having a JIS standard opening of 38μ and using a powder passing through a 38μ sieve) :): 2
After adding 0 parts by weight and forcibly stirring, 100 parts by weight of an aqueous dispersion of a thermosetting component was mixed, and dicyandiamide (a sieving with a JIS standard mesh 38 μ sieve as a curing agent of an epoxy resin thermosetting component was mixed. , Dicyandiamide that passed through a 38 μ sieve was used.): 1.5 parts by weight and 2-ethyl-4-methylimidazole as a curing catalyst: 0.1 parts by weight were added to obtain a resin varnish of the semi-invention. (Glass cloth) 2116 / AS891AW (manufactured by Asahi Schwabel Co., Ltd.) surface-treated with a special aminosilane coupling agent was used. (Preparation of prepreg) The resin varnish was stored in a bath, passed through a glass cloth, the excess resin varnish was scraped off with a slit having a gap of 0.35 mm, and the resin varnish of the present invention was dried for 3 minutes at 150 ° C. Got

[0058]

Example 5 (Preparation of polyphenylene ether aqueous dispersion)
By the same method as in Example 1, an aqueous dispersion of polyphenylene ether was obtained. (Preparation of Aqueous Dispersion of Thermosetting Component) Orthocresol novolac type epoxy resin self-emulsion modified product (Epilets 6
006W70 (registered trademark) Yuka Shell Epoxy Co., Ltd.
50 parts by weight of resin content, self-emulsified modified bisphenol A type epoxy resin (Epilets 3515W60
(Registered trademark) Yuka Shell Epoxy Co., Ltd. resin content 5
0 parts by weight were mixed, and distilled water was added so that the resin solid content was 50% by weight.

(Preparation of resin varnish) Aqueous dispersion of polyphenylene ether: 100 parts by weight of decabromodiphenylethane as a flame retardant (sieving with a sieve having a JIS standard opening of 38μ and using a powder passing through a 38μ sieve) :): 2
After adding 0 parts by weight and forcibly stirring, 100 parts by weight of an aqueous dispersion of a thermosetting component was mixed, and dicyandiamide as a curing agent for the thermosetting component (sieving with a 38 μ sieve according to JIS standard, 38 μ Dicyandiamide which passed through a sieve of (4) was used.): 4.5 parts by weight, 2-ethyl-4-methylimidazole (hereinafter 2E4MZ) as a curing catalyst: 0.1
Parts by weight were added to obtain a resin varnish of the present invention. (Glass cloth) 2116 / AS891AW (manufactured by Asahi Schwabel Co., Ltd.) surface-treated with a special aminosilane coupling agent was used. (Preparation of prepreg) After the resin varnish was stored in a bath and passed through a glass cloth, the excess resin varnish was scraped off with a slit having a gap of 0.35 mm and dried at 170 ° C for 3 minutes, and the prepreg using the resin varnish of the present invention was used. Got

[0060]

Example 6 (Preparation of emulsion) Polyphenylene ether:
100 parts by weight of hot toluene at 50 ° C. was dissolved in 100 parts by weight, and a tetrafunctional glycidylamine type epoxy resin represented by the general formula (6) (Epicoat 604 (registered trademark) manufactured by Yuka Shell Epoxy Co., Ltd.): 50 Parts by weight, orthocresol novolac type epoxy resin MEK solution (Epicoat 1
80 parts of 80S70B75 (registered trademark) manufactured by Yuka Shell Epoxy Co., Ltd.) was added to 50 parts by weight of a resin obtained by heating and vacuum removing MEK, and HL was added as a surfactant while heating at 50 ° C.
Polyoxyethylene nonylpropenyl phenyl ether having a B value of 17.9 (Aqualon RN-50 (registered trademark) manufactured by Daiichi Kogyo Seiyaku Co., Ltd.): 5.0 parts by weight was added, and 100 parts by weight of distilled water was added while forcibly stirring. Is added to prepare an aqueous dispersion of a thermosetting component, and this aqueous dispersion is heated to 95 ° C. to remove toluene under vacuum, and distilled water is added to a solid content of 50% by weight.
A mixed aqueous dispersion of was prepared.

(Preparation of resin varnish) The mixed aqueous dispersion was treated with JI
Particles that do not pass through 106 μm with a standard sieve opening of S of 106 μm were removed, and decabromodiphenylethane (JI) as a flame retardant was added to 100 parts by weight of the mixed water dispersion.
The powder was passed through a 38-μ sieve having an S-standard mesh and passed through a 38-μ sieve. ): After adding 20 parts by weight and forcibly stirring, dicyandiamide was used as a curing agent for the thermosetting component (using dicyandiamide which passed through a 38 μ sieve according to JIS standard and sieved). 5
By weight, 2-ethyl-4-methylimidazole as a curing catalyst: 0.1 part by weight was added to obtain a resin varnish of the present invention. (Glass cloth) 2116 / AS891AW (manufactured by Asahi Schwabel Co., Ltd.) surface-treated with a special aminosilane coupling agent was used. (Preparation of prepreg) After the resin varnish was stored in a bath and passed through a glass cloth, the excess resin varnish was scraped off with a slit having a gap of 0.35 mm and dried at 170 ° C for 3 minutes, and the prepreg using the resin varnish of the present invention was used. Got

[0062]

[Example 7] (Preparation of polyphenylene ether aqueous dispersion)
By the same method as in Example 1, an aqueous dispersion of polyphenylene ether was obtained. (Preparation of Aqueous Dispersion of Thermosetting Component) Diallyl isophthalate prepolymer (Isodap (registered trademark) manufactured by Daiso Co., Ltd.): 80 parts by weight, diallyl terephthalate (manufactured by Daiso Co., Ltd.): 20 parts by weight, 1, as a curing catalyst
4 (or1,3) -bis ((t-butyldioxy) isopropyl) benzene (Perbutyl P (registered trademark) manufactured by NOF CORPORATION): 10 parts by weight, polyoxyethylene nonyl having an HLB value of 17.9 as a surfactant. Propenyl phenyl ether (Aqualon RN-50 (registered trademark) manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.): 5.0 parts by weight are mixed, and 95 parts by weight of distilled water is added while forcibly stirring to obtain a thermosetting component. A water dispersion of

(Preparation of resin varnish) Aqueous dispersion of polyphenylene ether: 100 parts by weight of decabromodiphenylethane as a flame retardant (screened by a 38 μ sieve according to JIS standard, and a powder passing through a 38 μ sieve was used. :): 2
After adding 0 part by weight and forcibly stirring, 100 parts by weight of an aqueous dispersion of a thermosetting component was mixed to obtain a resin varnish of the present invention. (Glass cloth) 2116 / AS760AW surface-treated with silane coupling agent for special radical polymerization
(Asahi Schebel Co., Ltd.) was used. (Preparation of prepreg) The resin varnish was stored in a bath, passed through a glass cloth, the excess resin varnish was scraped off with a slit having a gap of 0.35 mm, and the resin varnish of the present invention was dried for 3 minutes at 150 ° C. Got

[0064]

Comparative Example 1 (Preparation of resin varnish) Methyl ethyl ketone solution of low brominated epoxy resin (Epicoat 5046B80
(Registered trademark) manufactured by Yuka Shell Epoxy Co., Ltd .: 80 parts by weight of resin component, orthocresol novolac type epoxy resin (Epicoat 180S70B75 (registered trademark) manufactured by Yuka Shell Epoxy Co., Ltd.): 20 parts by weight of resin component Then, N, N-dimethylformamide was added to 50% by weight of the resin content of the resin varnish, and dicyandiamide (as a curing agent was sieved with a sieve having a JIS standard opening of 38μ, 38μ
Dicyandiamide was passed through a sieve. ): 2.
5 parts by weight and 0.1 part by weight of 2-ethyl-4-methylimidazole as a curing catalyst were added to obtain a resin varnish containing no organic polyphenylene ether.

(Glass cloth) 2116 / AS891 surface-treated with a special aminosilane coupling agent
AW (manufactured by Asahi Schebel Co., Ltd.) was used. (Preparation of prepreg) The resin varnish was stored in a bath, passed through a glass cloth, the excess resin varnish was scraped off with a slit having a gap of 0.35 mm, dried at 170 ° C. for 3 minutes, and polyphenylene ether was added in an organic solvent system. A prepreg using a non-resin varnish was obtained.

[0066]

Comparative Example 2 (Preparation of Aqueous Dispersion of Epoxy Resin) Methyl ethyl ketone solution of low brominated epoxy resin (Epicoat 5
046B80 (registered trademark) Yuka Shell Epoxy Co., Ltd.
80 parts by weight of resin content, orthocresol novolac type epoxy resin (Epicoat 180S70B75 (registered trademark) manufactured by Yuka Shell Epoxy Co., Ltd.): 20 parts by resin content
After mixing 1 part by weight, MEK is removed by heating under vacuum, and the temperature is 80 ° C.
Polyoxyethylene nonylphenyl ether having an HLB value of 19 (Neugen EA-170 (registered trademark) manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)): 1.0 part by weight, HL
Polyoxyethylene nonylphenyl ether having a B value of 12 (Neugen EA-120 (registered trademark) manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.): 1.0 part by weight, polyoxyethylene nonylphenyl ether having an HLB value of 6 (Neugen EA-5
0 (registered trademark) manufactured by Daiichi Kogyo Seiyaku Co., Ltd.): 1.0 part by weight, and 97 parts by weight of distilled water with forced stirring to obtain an aqueous dispersion of a thermosetting component. It was

(Preparation of resin varnish) Aqueous dispersion of epoxy resin: 100 parts by weight were mixed, and dicyandiamide as a curing agent for the thermosetting component (sieve through a sieve having a JIS standard opening of 38μ and passed through a 38μ sieve). Dicyandiamide), which is 2.5 parts by weight, and 2-ethyl-4-methylimidazole: 0.1 part by weight as a curing catalyst, and polyphenylene ether is not blended, and the solvent is 90% by weight or more of water. I got a varnish. (Glass cloth) 2116 / AS891AW (manufactured by Asahi Schwabel Co., Ltd.) surface-treated with a special aminosilane coupling agent was used. (Preparation of prepreg) The resin varnish was stored in a bath, passed through a glass cloth, the excess resin varnish was scraped off with a slit having a gap of 0.35 mm, dried at 170 ° C for 3 minutes, and polyphenylene ether was not blended, and the solvent was water. A prepreg using 90% by weight or more of resin varnish was obtained.

[0068]

Comparative Example 3 A polymer type surfactant (Discoat N-14 (registered trademark) manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was added in an amount of 1.0 part by weight to 98.5 parts by weight of distilled water. , Acetylene glycol as a defoaming agent (Surphenol 104
(Registered trademark) manufactured by Nissin Chemical Industry Co., Ltd.) was added to the solvent in which 0.5 parts by weight was added and stirred, and 106 μ without sieving operation.
100 parts by weight of powdered polyphenylene ether (number average molecular weight of 7,000) containing particles larger than m was added and stirred with a homogenizer to obtain an aqueous dispersion of polyphenylene ether. Thereafter, in the same manner as in Example 1, 106 μm
A resin varnish containing 90% by weight or more of water and a prepreg using the resin varnish were obtained by blending polyphenylene ether containing larger particles.

[0069]

Comparative Example 4 (Preparation of Resin Varnish) 100 parts by weight of polyphenylene ether was dissolved in 200 parts by weight of hot toluene at 50 ° C., and triallyl isocyanate (TAIC (registered trademark) manufactured by Nippon Kasei Co., Ltd.): 80 parts by weight Parts, diallyl terephthalate (manufactured by Daiso Co., Ltd.): 20 parts by weight, and 1,4 (or1,3) -bis ((t-butyldioxy) isopropyl) benzene (Perbutyl P as a curing catalyst.
(Registered trademark) manufactured by NOF CORPORATION: 10 parts by weight, decabromodiphenylethane as a flame retardant (sieving with a sieve having a JIS standard opening of 38μ and using a powder passing through a 38μ sieve) : 20 parts by weight was added to obtain a resin varnish in which polyphenylene ether was dissolved in an organic solvent system. (Glass cloth) 2116 / AS760AW surface-treated with silane coupling agent for special radical polymerization
(Asahi Schebel Co., Ltd.) was used. (Preparation of prepreg) The resin varnish was stored in a bath that can be kept warm at 50 ° C, passed through a glass cloth, and the excess resin varnish was scraped off with a slit having a gap of 0.35 mm.
A prepreg using a resin varnish in which polyphenylene ether was dissolved in an organic solvent system was obtained by drying at 5 ° C for 5 minutes.

[Evaluation Method] (1) Evaluation of Resin Unimpregnated Part of Prepreg The cross section of the glass cloth impregnated with the resin in the warp yarn direction and the weft yarn direction cross section in the prepreg was measured in each direction using an electron microscope. 100 bundles were observed, the number of yarn bundles in which the resin unimpregnated portion was generated was counted, and the generation rate of the yarn bundle in which the resin unimpregnated portion was generated was evaluated. (2) Four glass transition temperature prepregs of the laminated plate are laminated, copper foil having a thickness of 18 μm is laminated on both surface layers thereof, and 180 ° C. under the conditions of 190 ° C. and 120 M · Pa.
It was heat-molded under pressure for 1 minute to prepare a 0.8 mm-thick double-sided copper-clad laminate. The copper foil of this laminate was removed by etching, washed with water and air-dried, and then the viscoelastic behavior was measured with RDAII (manufactured by Rheometrics Co., Ltd.) at a temperature rising rate of 3 ° C./minute, and the temperature at which the tan δ peak appeared. Was taken as the glass transition temperature.

(3) Four solder heat-resistant prepregs of a laminated board were laminated, and copper foil having a thickness of 18 μm was laminated on both surface layers thereof, and 180 at 190 ° C. and 120 M · Pa.
It was heat-molded under pressure for 1 minute to prepare a 0.8 mm-thick double-sided copper-clad laminate. The copper foil of this double-sided copper-clad laminate is removed by etching, washed with water, and dried by heating at 130 ° C. for 2 hours.
Cut into 50mm x 50mm, 90% relative humidity at 40 ℃
Exposed to the conditions of above for a certain time,
Immersion was carried out for 2 seconds, and the generated defects were observed. (4) Using the solder heat resistance evaluation sample of the laminate having the hygroscopic property (3),
Weight after drying at 130 ° C for 2 hours and relative humidity at 40 ° C 9
The weight difference after exposure for a certain time to the condition of 0% was calculated as the moisture absorption amount.

(5) 20 pieces of prepregs for measuring dielectric constant and dielectric loss tangent were piled up, and a copper foil having a thickness of 18 μm was piled up on both surface layers, and 18 sheets were formed under the conditions of 190 ° C. and 120 MPa.
It was pressed and heated for 0 minutes to form a double-sided copper-clad laminate having a thickness of 0.8 mm. The dielectric constant and dielectric loss tangent of this laminated plate at 1 MHz were measured according to JIS-K-6911 "General Test Method for Thermosetting Plastics". (6) Evaluation of low-pressure formability of laminated plate Four prepregs were superposed, copper foil having a thickness of 18 μm was superposed on both surface layers thereof, and press-molded under a condition of 190 ° C. and 30 M · Pa for 180 minutes to give a thickness of 0. A 0.8 mm double-sided copper-clad laminate was prepared. The cross section of the glass cloth in the laminated plate in the warp yarn direction and the weft yarn direction is observed in each direction using an electron microscope to count 100 yarn bundles, and the number of yarn bundles in which the resin unimpregnated portion is generated is counted. The generation rate of the resin-impregnated part-generated yarn bundle was evaluated. The test results for Examples 1 to 7 and Comparative Examples 1 to 4 are shown in Tables 1 to 3.

[0073]

[Table 1]

[0074]

[Table 2]

[0075]

[Table 3]

As is clear from Tables 1, 2, and 3, the glass cloths obtained in Examples 1 to 7 were impregnated with the resin varnish, and the resin varnish was treated with ( a) The particle system comprises a polyphenylene ether having a particle size of 106 μm or less, (b) a thermosetting monomer and / or a thermosetting component of a thermosetting polymer, and (c) a solvent composition containing 90% by weight or more of water. When using a prepreg manufactured using a resin varnish, the prepreg of the normal epoxy resin obtained by the solvent-soluble varnish of Comparative Example 1 and the polyphenylene ether having a particle size of the polyphenylene ether of Comparative Example 3 larger than 106 μm are used. Compared with a prepreg made of water-dispersed varnish, it has less resin-impregnated parts and is superior in heat resistance, moisture absorption resistance, and electrical characteristics of the laminate. . In addition, the heat resistance, moisture absorption resistance, and electric characteristics of the laminate are superior to those of the epoxy resin prepreg prepared by the water dispersion varnish containing no polyphenylene ether in Comparative Example 2. In addition, as compared with the prepreg using the polyphenylene ether of Comparative Example 4 and the hot toluene-dissolved varnish of the allyl polymerization thermosetting component, the solvent is water, so the influence on the environment is extremely small, and the resin-impregnated portion is generated. Less and excellent low-pressure formability of the laminated plate.

[0077]

INDUSTRIAL APPLICABILITY The resin varnish and the prepreg manufacturing method of the present invention can produce a prepreg without a resin unimpregnated portion and without adversely affecting the global environment and working environment.
It is possible to obtain a laminated board having excellent characteristics.

Continued front page    F-term (reference) 4F072 AA04 AA07 AB09 AB28 AB30                       AD03 AD23 AD38 AD42 AE23                       AF14 AG03 AH03 AJ04 AJ11                       AK02 AK05 AL13                 4J002 BQ001 CH072 DE028 DL006                       FD317

Claims (4)

[Claims] 1. A method for producing a prepreg by coating and impregnating a glass cloth with a resin varnish, followed by heating and drying.
(A) Polyphenylene ether and / or modified polyphenylene ether having a particle diameter of 106 μm or less, (b) a thermosetting monomer and / or a thermosetting polymer as a thermosetting component, and (c) 90 weight parts of water as a solvent. % Or more of a resin varnish is used, and a method for producing a prepreg. 2. The method for producing a prepreg according to claim 1, wherein the thermosetting component (b) is triallyl isocyanurate and / or triallyl cyanurate and a diallyl phthalate monomer. 3. The resin varnish has (a) a particle size of 106 μm.
m or less polyphenylene ether and / or modified polyphenylene ether in the form of an emulsion and / or dispersion dispersed by a surfactant containing a polymeric surfactant, and (b) the thermosetting component is The method for producing a prepreg according to claim 1 or 2, wherein the prepreg is contained in a state of being dispersed by a reactive surfactant having a saturated double bond. 4. The method for producing a prepreg according to claim 1, wherein the prepreg is heated to 130 ° C. or higher and 180 ° C. or lower in the heating step after impregnating the glass cloth with the resin varnish.