JP3173333B2 - 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 used for producing a laminate having excellent dielectric characteristics in a so-called ultra-high frequency region such as an X band (8 to 12 GHz) region used for satellite communication and the like. Things.

[0002]

2. Description of the Related Art An X band (8
〜12 GHz) region, that is, a laminate used in a so-called ultra-high frequency region is required to have excellent high-frequency characteristics, particularly excellent dielectric characteristics.

That is, the material must have a constant dielectric constant and a low dielectric loss tangent over a wide range of high frequencies, a temperature range, and a humidity range, and preferably have a small dielectric loss tangent. Heretofore, a laminate containing a polyphenylene ether resin has been used for such an application. In order to shorten the circuit, a material having a large dielectric constant and a small dielectric loss tangent is required, and a polyphenylene ether-based laminate containing an inorganic filler to adjust the dielectric constant is required. Boards are being used.

As a method of manufacturing such a laminated board, a transparent resin solution in which a resin component such as polyphenylene ether resin is dissolved in a solvent such as trichloroethylene is prepared, and then an inorganic filler is dispersed in the transparent resin solution. Generally, a method was used in which a resin composition was prepared, the substrate was impregnated with the resin composition, heated and dried to produce a prepreg, and the prepreg was laminated by heating.

However, the choice of a solvent for forming a transparent resin solution is greatly limited in terms of the solubility of resin components such as polyphenylene ether resin, and specifically, it is not preferable in terms of environmental problems. A halogenated solvent such as trichloroethylene has been used, and a method for producing a laminate having excellent dielectric properties without using a halogenated solvent has been demanded.

Therefore, a method for producing a prepreg by heating and holding a resin liquid as described in, for example, Japanese Patent Publication No. 63-39404 is considered as one of the methods for making a non-halogen solvent usable. Further, the present inventors heated and mixed a liquid containing a resin component such as a polyphenylene ether resin and a non-halogen solvent once at a temperature of 35 ° C. or higher as a resin composition, and then cooled to obtain a dispersion of an opaque resin component. Then, a method of using a resin composition obtained by adding an inorganic filler to a dispersion of the resin component was studied. In this method, a non-halogen solvent was used, and the resin liquid was heated. A prepreg having a good appearance can be obtained without prerequisite to manufacture the prepreg while holding it, and as a result,
It has been found that a laminate having excellent performance can be manufactured (Japanese Patent Application No. 7-32045).

However, according to a subsequent study, when a resin composition is prepared using a non-halogen solvent, the viscosity of the resin composition becomes unstable depending on the production conditions, and the state of adhesion of the resin component to the base material is reduced. It has been found that the electrical characteristics of the laminate and the laminate greatly fluctuate, and it may not be possible to stably produce a laminate having excellent properties.

[0008]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide a resin component containing a polyphenylene ether resin,
A method for producing a prepreg in which a base material is impregnated with a resin composition containing an inorganic filler and a non-halogen solvent, and is heated and dried to obtain a prepreg having good adhesion between the base material and the adhered resin. Accordingly, it is an object of the present invention to provide a prepreg manufacturing method capable of stably manufacturing a laminate having excellent performance.

[0009]

According to a first aspect of the present invention, there is provided a method for producing a prepreg, comprising a polyphenylene ether resin, a crosslinkable resin of the following (a), a resin containing a crosslinker and a initiator of the following (b). Ingredients, inorganic filler, and a resin composition containing a non-halogen solvent impregnated in a substrate, in a method for producing a prepreg manufactured by heating and drying, the resin composition and the resin component excluding the inorganic filler and solvent Once heated to 35 ° C. or higher, and then cooled to form an opaque resin dispersion,
It is a resin composition obtained by adding and stirring an inorganic filler under the condition that the temperature of the resin dispersion is 20 to 30 ° C. (A) From the group consisting of 1,2-polybutadiene, 1,4-polybutadiene, styrene-butadiene, maleic-modified 1,2-polybutadiene, acrylic-modified 1,2-polybutadiene, epoxy-modified 1,2-polybutadiene and rubbers At least one selected. (B) Ester acrylates, epoxy acrylates, urethane acrylates, ether acrylates, melamine acrylates, alkyd acrylates, silicon acrylates, triallyl cyanurate, triallyl isocyanurate, ethylene glycol dimethacrylate, divinylbenzene, diallyl At least one selected from the group consisting of phthalate, vinyltoluene, ethylvinylbenzene, styrene, polyparamethylstyrene and polyfunctional epoxies.

[0010] According to a second aspect of the present invention, in the method for producing a prepreg according to the first aspect, the method of adding the inorganic filler and stirring is performed by using a stirring blade. The shear rate is 10-100
[1 / sec].

According to a third aspect of the present invention, there is provided a method for producing a prepreg according to the first or second aspect, wherein the polyphenylene ether resin, the crosslinkable resin (a), and the (b) Wherein the inorganic filler is contained in an amount of 1 to 300 parts by weight based on a total of 100 parts by weight of the crosslinking assistant.

According to a fourth aspect of the present invention, there is provided the prepreg manufacturing method according to any one of the first to third aspects, wherein the inorganic filler is a titanium dioxide-based ceramic or a barium titanate-based. At least one selected from the group consisting of ceramic, lead titanate ceramic, strontium titanate ceramic, calcium titanate ceramic, bismuth titanate ceramic, magnesium titanate ceramic, and lead zirconate ceramic Characterized by the following:

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The polyphenylene ether resin (hereinafter referred to as PPE) constituting the resin composition of the present invention is also referred to as polyphenylene oxide resin, and is represented by the following formula 1, for example.

[0014]

Embedded image

In the above general formula 1, R represents hydrogen or carbon atom 1
Represents 3 to 3 hydrocarbon groups, each R may be the same,
It may be different. N is a positive number representing the number of repetitions.

An example of PPE is poly (2,6-dimethyl-1,4-phenylene oxide). Such PPE is described, for example, in US Pat.
No. 8 can be synthesized by the method disclosed in the specification. Although not particularly limited, for example, the weight average molecular weight is about 50,000, and the weight average molecular weight / number average molecular weight = 4.2.
Are preferably used.

The crosslinkable resin used in the present invention is the above (a), and the crosslinker is the above (b). As a crosslinking aid, triallyl cyanurate or triallyl isocyanurate in the above (b) has good compatibility with PPE, and is preferred in terms of crosslinking properties, heat resistance and dielectric properties.

The initiators used in the present invention include dicumyl peroxide, t-butylcumyl peroxide,
Di-t-butyl peroxide, 2,5-dimethyl-
2,5-di-t-butylperoxyhexyne-3,2,2
5-di-t-butylperoxyhexane, α, α′-bis (t-butylperoxy-m-isopropyl) benzene [1,4 (or 1,3) -bis (t-butylperoxyisopropyl) benzene Also called. And the like. In addition, a commercial initiator "Biscumyl" (1 minute half-life temperature of 330 ° C.) manufactured by NOF Corporation, which is not a peroxide but is a commercially available initiator, can also be used.

The mixing ratio of the above-mentioned raw materials is not particularly limited, but it is preferable that the ratio is 20 to 90% by weight of PPE, 5 to 60% by weight of a crosslinkable resin, and 1 to 50% by weight of a crosslinking assistant. .

The non-halogen solvent used in the present invention is a solvent that can be removed by heating or the like. Specific examples thereof include, but are not limited to, benzene, toluene, xylene, ketones, and alcohols. And the like.

The inorganic filler used in the present invention includes titanium dioxide ceramic, barium titanate ceramic, lead titanate ceramic, strontium titanate ceramic, calcium titanate ceramic, bismuth titanate ceramic, titanium Magnesium silicate ceramics, lead zirconate ceramics and the like can be mentioned.
These are not limited to one kind, and two or more kinds may be combined. The particle size of the inorganic filler is 0.1-50μ
m is desirable, and if it is out of this range, the dispersion of the inorganic filler becomes worse, and the impregnation property to the base material decreases.

In order to improve the adhesion between the inorganic filler and the resin, and between the resin and the metal foil, a coupling agent may be added to the resin composition.

The mixing ratio of the inorganic filler is in the range of 1 to 300 parts by weight with respect to the total of 100 parts by weight of the PPE, the crosslinkable resin and the crosslinking aid, and the dielectric constant is controlled. It is desirable to produce a prepreg with sufficient effects and good appearance.

The method for producing a prepreg according to the present invention comprises:
A resin composition is obtained by mixing and stirring the respective raw materials, and the resin composition is impregnated into a base material and dried by heating to produce the resin composition. When the respective raw materials are mixed and stirred, a liquid containing the polyphenylene ether resin, the crosslinkable resin (a), the cross-linking aid (b), the initiator, and the non-halogen solvent is once mixed with 35 parts.
After heating and mixing at a temperature of at least ℃, the mixture is cooled to form an opaque resin dispersion. In addition, when adding the inorganic filler, it is important to add the resin while stirring the resin dispersion at a temperature of 20 to 30 ° C. If the temperature is lower than 20 ° C., the precipitation in the resin composition Since the number of components increases, the viscosity of the resin composition increases, and the temperature of the resin composition becomes 3
If the temperature is 0 ° C. or higher, the precipitated components of the resin formed by cooling are re-melted, and the viscosity of the resin composition increases. In such a resin composition, the dispersion of the inorganic filler becomes poor, and the impregnation property of the base material is greatly reduced. When the impregnating property to the base material is reduced, the prepreg obtained from this resin is not sufficiently adhered to the base material and the adhered resin, so that when the prepreg is handled, the resin peels off from the base material. A laminate obtained by molding such a prepreg has poor copper foil peeling strength, poor solder heat resistance, and unstable electrical properties such as a dielectric constant.

When adding the inorganic filler, the stirring method at the time of adding the filler and after the addition is such that the stirring is performed using a stirring blade, and the shear rate is 10 to 100 [1 / sec].
And when the shear rate is less than 10,
When the dispersion of the inorganic filler becomes poor and the shear rate exceeds 100, the viscosity of the resin composition is increased due to re-melting of the precipitated component in the resin composition and coarsening of the structure of the inorganic filler and the precipitated component. And the impregnating property of the base material is reduced, and the obtained prepreg does not have sufficient adhesion between the base material and the adhered resin. Therefore, when the prepreg is handled, the resin is easily peeled off from the base material. The above shear rate is a value that can be obtained from the following equation.

Shear rate = π × L × n ÷ t ÷ 60 [1 / sec] π: Pi, L: Diameter of stirring blade [mm], n: Rotation speed of stirring [rpm], t: Stirring blade In the present invention, a prepreg is produced by impregnating a base material with the resin composition and drying by heating. The substrate is not particularly limited, but a cloth, mat, or nonwoven fabric using fibers such as glass fiber, aramid fiber, polyester fiber, and nylon fiber, or paper such as kraft paper and linter paper can be used. The resin amount of the prepreg is not particularly limited, but is preferably 30 to 60% by weight to obtain good properties.

When impregnating the base material with the resin composition, the resin composition was stored after stirring under the condition of a temperature of 20 to 30 ° C., and the temperature of the resin composition at the time of impregnation was 20 to 30 ° C. ℃ is desirable, and the temperature is 2
If the temperature is lower than 0 ° C., the amount of precipitated components in the resin composition increases, so that the viscosity of the resin composition increases, resulting in a resin composition having a high viscosity at the time of impregnation, and when the temperature is 30 ° C. or higher. As a result, the precipitated components of the resin are remelted, the viscosity of the resin composition increases, and the resin composition has a high viscosity at the time of impregnation.
In such a resin composition, the impregnation property of the base material is reduced, and the obtained prepreg has insufficient adhesion between the base material and the adherent resin. Likely to happen.

A predetermined number of the prepregs obtained by the present invention are combined, and if necessary, metal foils are combined, and heated and pressed to obtain a laminate. The laminate thus obtained does not impair the properties of the PPE and is a laminate excellent in high-frequency characteristics such as dielectric characteristics and heat resistance.

[0029]

EXAMPLES In the following Examples and Comparative Examples, the raw materials shown in Table 1 were used. The raw materials shown in Table 1 are used as PPE in Japan G.P. E. FIG. Poly (2,6-dimethyl-1,4-phenylene oxide) having a weight average molecular weight of 54000, manufactured by Plastics Co., Ltd., and a styrene-butadiene copolymer (SBS) as a crosslinkable resin; As triallyl isocyanurate (TAIC)
And dicumyl peroxide (D
CP) and the average particle size is 0.3μ as the inorganic filler.
m of titanium dioxide and toluene as a non-halogen solvent. SBS was Asaprene manufactured by Asahi Kasei Kogyo Co., Ltd., TAIC was manufactured by Nippon Kasei Co., Ltd., titanium dioxide was TR-840 manufactured by Fuji Titanium Co., Ltd., and toluene was a special grade reagent. .

(Examples 1-4, Comparative Examples 1-2) 50 parts by weight of PPE, 10 parts by weight of crosslinkable resin (SBS), 40 parts by weight of crosslinking aid (TAIC), and initiator (DCP) 2
Parts by weight, and 238 parts by weight of a solvent (toluene) in a separable flask.
Warmed to ° C. After heating at 80 ° C. for 2 hours, the mixture was air-cooled to obtain an opaque resin dispersion. 200 parts by weight of an inorganic filler, titanium dioxide, was added to the resin dispersion at the temperature shown in Table 1, and the mixture was stirred at a shear rate shown in Table 1 for 3 hours to obtain a resin composition. Stirring is 2 liters in volume and the inner diameter of the body is 170
mm in a separable flask of T.K. K. This was performed by a disper (blade diameter: 40 mm). After stopping the stirring, the resin composition was stored under the storage conditions shown in Table 1 for 3 hours, and then the substrate was impregnated at the stored temperature.

The viscosity of the obtained resin composition was evaluated by measuring it at 25 ° C. with a B-type viscometer. Viscosity was determined to be good when the viscosity was less than 400 centipoise due to the impregnation property of the substrate, and poor when the viscosity was 400 centipoise or more.

The resin composition obtained as described above has a thickness of 0.1
impregnated in a glass cloth made of E-glass
A prepreg having a resin content of 66% was obtained by treating at 3 ° C. for 3 minutes. The obtained prepreg was evaluated for handleability as an evaluation of the adhesion between the base material and the adhered resin.
It was shown to. The handleability was determined by folding a 200 mm square prepreg into two pieces and evaluating whether or not the resin was peeled off.

Further, the four prepregs obtained above were stacked, copper foil having a thickness of 18 μm was stacked on both sides thereof, and then pressed at 210 ° C. and a pressure of 30 kg / cm ² for 60 minutes to obtain a double-sided copper-clad laminate. Obtained. The copper foil peel strength, PCT solder heat resistance, dielectric constant, and dielectric loss tangent of the obtained double-sided copper-clad laminate were evaluated. The results are shown in Table 1. The copper foil peeling strength was measured at a crosshead speed of 50 mm / min using a 10 mm × 100 mm test piece, and the PCT solder heat resistance was 50 mm × 50 obtained by removing the copper foil by etching.
After treating the test piece of 1 mm under the condition of 134 ° C. and 3 atm for 1 hour, the test piece was floated in a solder bath at 260 ° C. for 1 minute to check for abnormalities such as swelling, and the dielectric constant and the dielectric loss tangent were measured.
It was evaluated by the method of the United States Army Inspection Standard (MIL).

From the results shown in Table 1, the examples of the present invention have a better viscosity of the resin composition than the comparative examples, and the handleability of the obtained prepreg, that is, the excellent adhesion between the base material and the adhered resin is excellent. Further, it was confirmed that the obtained laminate had excellent copper foil peeling strength, PCT solder heat resistance, and dielectric constant.

[0035]

[Table 1]

[0036]

According to the method for producing a prepreg according to the first to fourth aspects of the present invention, a prepreg having good adhesion between the substrate and the adhered resin can be stably obtained, and as a result, the copper foil peeling strength can be improved. Thus, it is possible to stably manufacture a laminated board having excellent properties such as solder heat resistance and dielectric constant.

────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI C08L 71/12 C08L 71/12 // C08F 291/00 C08F 291/00 (56) References JP-A-8-225665 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C08J 5/24 CEZ C08G 59/40 C08K 3/00 C08L 47/00 C08L 63/00 C08L 71/12 C08F 291/00

Claims (4)

(57) [Claims] 1. A resin composition containing a polyphenylene ether resin, a crosslinkable resin of the following (a), a crosslinker and an initiator of the following (b), an inorganic filler, and a non-halogen solvent. In a method for producing a prepreg, which is impregnated into a base material and dried by heating, the resin composition is prepared by heating a resin component and a solvent excluding an inorganic filler to 35 ° C. or higher, and then cooling to opaque. A method for producing a prepreg, which is a resin composition obtained by adding a mineral filler and stirring the resin dispersion at a temperature of 20 to 30 ° C. after forming the resin dispersion. (A) From the group consisting of 1,2-polybutadiene, 1,4-polybutadiene, styrene-butadiene, maleic-modified 1,2-polybutadiene, acrylic-modified 1,2-polybutadiene, epoxy-modified 1,2-polybutadiene and rubbers At least one selected. (B) Ester acrylates, epoxy acrylates, urethane acrylates, ether acrylates, melamine acrylates, alkyd acrylates, silicon acrylates, triallyl cyanurate, triallyl isocyanurate, ethylene glycol dimethacrylate, divinylbenzene, diallyl At least one selected from the group consisting of phthalate, vinyltoluene, ethylvinylbenzene, styrene, polyparamethylstyrene and polyfunctional epoxies. 2. A stirring method for adding and stirring an inorganic filler is such that stirring is performed using a stirring blade, and the shear rate is 1%.
2. The method according to claim 1, wherein the value is 0 to 100 [1 / sec].
A method for producing the prepreg according to the above. 3. An inorganic filler is contained in an amount of 1 to 300 parts by weight based on 100 parts by weight of the total of the polyphenylene ether resin, the crosslinkable resin (a) and the crosslinker (b). A method for producing a prepreg according to claim 1. 4. An inorganic filler comprising a titanium dioxide-based ceramic, a barium titanate-based ceramic, a lead titanate-based ceramic, a strontium titanate-based ceramic, a calcium titanate-based ceramic, a bismuth titanate-based ceramic, a magnesium titanate-based ceramic, The method for producing a prepreg according to any one of claims 1 to 3, wherein the prepreg is at least one type of ceramic selected from the group consisting of lead zirconate-based ceramics.