JP3221951B2 - Manufacturing method of prepreg - Google Patents

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 prepreg.

[0002]

2. Description of the Related Art In recent years, there has been a remarkable trend toward miniaturization and high-density mounting methods in the field of electronic devices for communication, consumer use, industrial use, and the like, and accordingly, materials have become more excellent. Heat resistance, dimensional stability, and electrical properties are being demanded. For example, a copper-clad laminate made of a thermosetting resin such as a phenol resin or an epoxy resin has been used as a printed wiring board. Although these have various performances in a well-balanced manner, they have a drawback that electrical characteristics, particularly, dielectric characteristics in a high frequency range are poor. As a new material for solving this problem, polyphenylene ether has recently attracted attention and is being applied to copper-clad laminates.

[0003] A method for producing a laminated board is generally produced by laminating a prepreg, which is obtained by impregnating a base material such as paper or glass fiber with a resin solution (varnish) and drying, with a metal foil. Therefore, the prepreg manufacturing method is very important. When polyphenylene ether is used as the resin composition for a laminate, the solvent used for preparing the prepreg is desirably a solvent that dissolves polyphenylene ether. Solvents for dissolving polyphenylene ether include dichloromethane, chloroform,
Examples thereof include halogen solvents such as trichloroethylene, aromatic solvents such as benzene, toluene, and xylene, and THF. These solvents are used alone or in combination of two or more.

However, at present, halogen-based solvents have a large effect on the human body and are becoming difficult to use. Therefore, it is desired to use an aromatic solvent, particularly toluene, as a solvent for preparing a prepreg. However, when toluene is used as a solvent for impregnating a prepreg, the viscosity of the solution increases (waxing), which hinders the production of the prepreg. It is the present condition that it comes.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a method for producing a prepreg of a polyphenylene ether-based resin composition without causing waxing, using toluene as a solvent. What you want to do.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, have found a manufacturing method which meets the object of the present invention by melting at a specific temperature or higher. The present invention has been completed. That is, the present invention relates to a method for producing a prepreg in which a polyphenylene ether-based resin composition is dissolved in toluene and impregnated into a substrate, wherein the resin composition is subjected to a temperature (T
C) or higher. T = 149.5G + 42.0 (I) [wherein T is a dissolution temperature (° C.), and G is G = (weight of polyphenylene ether in the resin composition)] / (Weight of toluene + weight of polyphenylene ether in the resin composition). Hereinafter, the present invention will be described in detail.

[0007] The polyphenylene ether resin used in the present invention includes a modified product. The polyphenylene ether used in the present invention is represented by the following general formula (1).

[0008]

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Examples of the lower alkyl group of R _{1 to} R ₄ in the general formula (A) include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group and an isobutyl group. Examples of the aryl group include a phenyl group. Examples of the haloalkyl group include a bromomethyl group and a chloromethyl group. Examples of the halogen atom include bromine and chlorine.

As a typical example of Q in the general formula (1),
Compound groups represented by the following four general formulas represented by the following chemical formula 2 are exemplified.

[0011]

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Specific examples include the general formulas and the like represented by the following chemical formulas (3) and (4).

[0013]

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[0014]

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The polyphenylene ether chain represented by J in the general formula (1) contains, in addition to the unit represented by the general formula (A), a unit represented by the following general formula: You may.

[0016]

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Preferred examples of the polyphenylene ether resin of the general formula (1) used in the present invention include poly (2,6) obtained by homopolymerization of 2,6-dimethylphenol.
-Dimethyl-1,4-phenylene ether), styrene graft polymer of poly (2,6-dimethyl-1,4-phenylene ether), copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol, 2,
Copolymer of 6-dimethylphenol and 2-methyl-6-phenylphenol, polyfunctional polyphenylene obtained by polymerization in the presence of 2,6-dimethylphenol and a polyfunctional phenol compound represented by the following general formula (6) Ether resins, for example, copolymers containing units of general formulas (A) and (B) as disclosed in JP-A-63-301222 and JP-A-1-297428 are exemplified.

[0018]

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(In the formula, m represents an integer of 2 to 6, and Q represents a polyfunctional phenol compound residue in the same manner as described above.) The molecular weight of the polyphenylene ether resin described above is 0.5 g at 30 ° C. / Dl having a viscosity number ηsp / c in the range of 0.1 to 1.0 can be favorably used. As a curable resin composition that emphasizes the flow of molten resin, for example, as a prepreg for a multilayer wiring board,
Resins having a low viscosity number are preferred.

The polyphenylene ether used in the present invention also includes a modified product. Specifically, JP-A-64-69628, JP-A-1-113425,
Examples thereof include a polyphenylene ether resin containing an unsaturated group, and a reaction product of a polyphenylene ether resin with an unsaturated carboxylic acid and / or acid anhydride disclosed in JP-A-1-113426.

Next, the polyphenylene resin composition of the present invention will be described. The polyphenylene ether-based resin composition is a resin composition containing the above-described polyphenylene ether (including a modified product), and a resin compounded in addition to the polyphenylene ether has a substrate property as a material for a printed board which is the object of the present invention. Anything that does not impair can be used. Specifically, phenol resin, epoxy resin, diallyl phthalate, divinyl benzene, polyfunctional acryloyl compound, polyfunctional methacryloyl compound, polyfunctional maleimide, polyfunctional methacryloyl compound, polyfunctional maleimide, polyfunctional cyanic acid Ester, polyfunctional isocyanate, unsaturated polyester, triallyl isocyanurate, triallyl cyanurate, polybutadiene, crosslinkable polymers such as styrene-butadiene / styrene-butadiene-styrene, various thermoplastic resins, various thermosetting resins And so on. These are generally blended for the purpose of improving the physical properties of a substrate produced by laminating and molding a prepreg.

Although not particularly limited, examples of preferred resin compositions include polyphenylene ether and triallyl isocyanurate and / or triallyl cyanurate; polyphenylene ether and epoxy resin; polyphenylene ether, styrene butadiene block copolymer and triallyl isocyanurate. And / or triallyl cyanurate; polyphenylene ether containing an unsaturated group and triallyl isocyanurate and / or triallyl cyanurate; polyphenylene ether containing an unsaturated group, triallyl isocyanurate and / or triallyl cyanurate, and epoxy resin A reaction product of a polyphenylene ether resin with an unsaturated carboxylic acid and / or acid anhydride, and triallyl isocyanurate And / or triallyl cyanurate; reaction product of polyphenylene ether resin with unsaturated carboxylic acid and / or acid anhydride and epoxy resin; reaction product of polyphenylene ether resin with unsaturated carboxylic acid and / or acid anhydride , Triallyl isocyanurate and / or triallyl cyanurate and epoxy resins. The amount is determined according to the purpose.

The substrate used in the present invention includes various glass cloths such as roving cloths, cloths, chopped mats, and surfacing mats, asbestos cloths, metal fiber cloths and other synthetic or natural inorganic fiber cloths; polyvinyl alcohol fibers, Woven or non-woven fabric obtained from synthetic fibers such as polyester fiber, acrylic fiber, wholly aromatic polyamide fiber and polytetrafluoroethylene fiber; natural fiber cloth such as cotton cloth, linen cloth and felt; carbon fiber cloth; kraft paper, cotton paper; Natural cellulose-based cloths such as paper-glass mixed fiber papers are used alone or in combination of two or more.

Further, a radical initiator may be contained for the purpose of lowering the reaction temperature or accelerating the crosslinking reaction of the unsaturated group. Representative examples of the radical initiator include benzoyl peroxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, and 2,5-dimethyl-2,5-di (t -Butylperoxy) hexyne-3, di-t-butyl peroxide, t-butylcumyl peroxide,
α, α′-bis (t-butylperoxy-m-isopropyl) benzene, 2,5-dimethyl-2,5-di (t-
Butylperoxy) hexane, dicumyl peroxide, di-t-butylperoxyisophthalate, t-butylperoxybenzoate, 2,2-bis (t-butylperoxy) butane, 2,2-bis (t- There are peroxides such as, but not limited to, butylperoxy) octane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, di (trimethylsilyl) peroxide, and trimethylsilyltriphenylsilyl peroxide. Although not a peroxide, 2,3-dimethyl-2,3-diphenylbutane can also be used as a radical initiator. However, the initiator used for curing the present resin composition is not limited to these examples.

In addition to the above-mentioned radical initiator, a curing accelerator may be used for the purpose of reacting the epoxy resin. Examples of the curing accelerator include amine compounds, imidazole compounds, nitrogen-containing heterocyclic compounds such as diazabicycloundecene, organic phosphine compounds, organic phosphine / organic boron complexes, quaternary ammonium compounds, and quaternary ammonium compounds.
Known compounds such as a grade phosphonium compound can be used. For details of the technology relating to the curing accelerator, see, for example, “Recent Advances in Epoxy Resins” edited by Hiroshi Kakiuchi,
90) See Chapter 4 and references therein.

In addition, a suitable curing agent for the polyfunctional maleimide is polyamine, and a suitable catalyst for the polyfunctional cyanate ester is mineral acid, Lewis acid, salts such as sodium carbonate or lithium chloride, tributylphosphine, etc. Examples of the catalysts and curing agents suitable for polyfunctional isocyanates include, for example, "Polyurethane Resin Handbook" edited by Keiji Iwata, Nikkan Kogyo Shimbun (198)
7) P.I. Examples include amines, organometallics, polyhydric alcohols and the like as taught in US Pat.

The above-mentioned catalyst, initiator, curing agent and the like are appropriately selected and used depending on the type of the resin composition. In the present invention, fillers and additives can be added to the resin composition in an amount within a range not impairing the original properties for the purpose of imparting desired performance according to the application. The filler may be in the form of fibers or powder, and may be silica, alumina,
Examples include talc, mica, glass beads, glass hollow spheres, and the like. Examples of the additives include an antioxidant, a heat stabilizer, an antistatic agent, a plasticizer, a pigment, a dye, and a colorant. For the purpose of further improving flame retardancy, chlorine-based,
Bromine-based and phosphorus-based flame retardants, Sb ₂ O ₃ , Sb ₂ O ₅ ,
A flame retardant aid such as NbSbO ₃ 3H ₂ O can be used in combination. Furthermore, one or two or more other thermoplastic resins or thermosetting resins can be blended.

The above polyphenylene ether-based resin composition is prepared and dissolved in a solvent. In the present invention, toluene is used as the solvent. Next, the temperature at which the resin composition of the present invention is dissolved will be described. It is an essential condition that the dissolution temperature is not lower than the temperature (T ° C.) shown below. T = 149.5G + 42.0 (I) [wherein T is a dissolution temperature (° C.), and G is the following formula G = (weight of polyphenylene ether in resin composition) / (weight of toluene) + Weight of polyphenylene ether in the resin composition). In the present invention, it is desirable that the polyphenylene ether (including the modified product) is dissolved at a temperature shown by the above formula at least until the dissolution is completed. Also, the melting temperature is the denaturation of the resin composition,
It is desirable to carry out the reaction within a range in which decomposition, and furthermore, boiling of the solution does not occur. Insufficient dissolution may promote waxing of the solution. In the present invention, the dissolution temperature when dissolving the polyphenylene ether-based resin composition is determined only by the weight fraction of polyphenylene ether and toluene.

When the substrate is impregnated, the impregnation temperature can be adjusted depending on the concentration of the solution.
C. or higher, more preferably 45.degree. C. or higher, even more preferably 50.degree. C. or higher. If the temperature is lower than 40 ° C., the waxing of the solution may be promoted. The impregnation can be repeated multiple times as necessary, and in this case, the impregnation can be repeated using multiple solutions having different compositions and concentrations to finally adjust the desired resin composition and resin amount It is.

As a flame retardant for a composite material including a substrate, a combination of brominated diphenyl ether and antimony oxide is preferably used.

[0031]

EXAMPLES Hereinafter, the present invention will be described with reference to examples to further clarify the present invention, but the scope of the present invention is not limited to these examples.

[0032]

Synthesis Example 1 Poly (2,500) having a viscosity number ηsp / c of 0.54 measured in a chloroform solution of 0.5 g / dl at 30 ° C.
100 parts by weight of 6-dimethyl-1,4-phenylene ether), 1.5 parts by weight of maleic anhydride, and 2,5-dimethyl-2,5-di (t-butylperoxy) hexane (Perhexa 25B manufactured by NOF Corporation) ) After dry blending 1.0 part by weight at room temperature, cylinder temperature 30
Extrusion was performed by a twin screw extruder under the conditions of 0 ° C. and a screw rotation speed of 230 rpm. This reaction product is designated as A.

[0033]

[Synthesis Example 2] Viscosity number η measured by the same method as in Synthesis Example 1.
poly (2,6-dimethyl-1,4 having an sp / c of 0.60
After dry-blending 100 parts by weight of (phenylene ether) and 1.5 parts by weight of maleic anhydride at room temperature, the mixture was extruded by a twin-screw extruder at a cylinder temperature of 300 ° C. and a screw rotation speed of 230 rpm. This reaction product is designated B.

[0034]

[Synthesis Example 3] Polyphenylene ether resin containing an unsaturated group, average substitution rate 14%, η measured by the same method as in Synthesis Example 1
An allyl group-substituted polyphenylene ether having an sp / c of 0.62 was prepared according to a known method disclosed in JP-A-64-69629, using a poly (2,6-
Dimethyl-1,4-phenylene ether). This allyl-substituted polyphenylene ether is designated as C.

[0035]

Examples 1 to 5 Poly (2,6-dimethyl-1,4-phenylene ether) of .eta.sp / c = 0.56 measured in the same manner as in A, B, C and Synthesis Example 1 (hereinafter referred to as D Was mixed with various compositions in the composition shown in Table 1 and dissolved in toluene at the temperature shown in Table 2 for 1 hour. Dissolution was performed promptly, and all resins were uniformly dissolved in toluene.

These solutions were cooled to the temperatures shown in Table 2, and one hour after reaching the predetermined temperature, a glass cloth (made of E glass, having a basis weight of 48 g / m ² or 105 g / m ^{2) was used.}
m ² ) was impregnated, and then dried in an air oven to prepare a prepreg. Each solution could be impregnated without causing waxing, and the surface condition of each prepreg was good.

[0037]

Comparative Examples 1-4 A and D were dissolved in toluene in the same composition as in Examples 2 and 3. The dissolution was performed at the temperature shown in Table 2 for 1 hour. These solutions were cooled to the temperatures shown in Table 2 and the same operations as in Examples 1 to 4 were performed to produce prepregs. The solution waxed upon cooling. The obtained prepreg had a cracked surface.

[0038]

[Table 1]

[0039]

[Table 2]

[0040]

The prepreg production method of the present invention is a process that does not use a halogen-based solvent, has less influence on the human body, and is a process in which waxing is suppressed. It is in good condition. Accordingly, the prepreg obtained by the production method of the present invention can be used as a dielectric material, an insulating material, a heat-resistant material, and the like in the fields of the electric industry, the electronics industry, the space and aircraft industries, and the like. In particular, it is suitably used as a prepreg for single-sided, double-sided, multi-layer printed boards, semi-rigid boards, metal base boards, and multi-layer printed boards.

Continuation of front page (56) References JP-A-3-275761 (JP, A) JP-A-2-58391 (JP, A) JP-A-2-58390 (JP, A) JP-A-4-161454 (JP) , A) JP-A-6-206955 (JP, A) European Patent Application Publication 126972 (EP, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08J 5/24 H05K 1/03 610

Claims (1)

(57) [Claims] 1. A method for producing a prepreg in which a polyphenylene ether-based resin composition is dissolved in toluene and impregnated into a substrate, wherein the resin composition is dissolved at a temperature (T ° C.) or higher represented by the following formula (I): A method for producing a prepreg. T = 149.5G + 42.0 (I) [wherein T is the melting temperature (° C.), and G is G = (weight of polyphenylene ether in resin composition) / (weight of toluene + (Weight of polyphenylene ether in the resin composition). ]