JPH08225665A - Production of laminate - Google Patents

Abstract

PURPOSE: To obtain a laminate excellent in dielectric properties in the superhigh frequency region by using a varnish prepd. from polyphenylene oxide, a specific resin component, an inorg. filler and a nonhalogen solvent in a specific manner. CONSTITUTION: (A) polyphenylene oxide, (B) a crosslinkable resin such as polybutadiene and (C) a crosslinking assistant resin such as an acrylate or a cyanurate are mixed with (D) a nonhalogen solvent at a temp. of at least 35 deg.C, followed by cooling to prepare a dispersion of the resin components. Subsequently, (E) an inorg. filler is added to the dispersion to prepare a varnish. The solvent is removed from the varnish to obtain resin compsn. sheets, which are then heated and laminated to form a laminate. Triallyl (iso)cyanurate is pref. as the component (C) because of its good compatibility with the component (A). Examples of the component (D) include benzene and toluene. Titani-um oxide and titanic acid salt ceramics high in dielectric constant are desirable as the component (E). An initiator such as dicumyl peroxide is pref. blended with the resin components.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a laminated plate having excellent dielectric properties in the so-called super high frequency range such as X band (10 GHz) range such as satellite communication.

[0002]

2. Description of the Related Art X band (1
Laminates used in so-called ultra-high frequency regions such as the 0 GHz) region are required to have excellent high frequency properties, particularly excellent dielectric properties.

That is, the material must have a constant dielectric constant and dielectric loss tangent in a wide frequency range, temperature range, and humidity range, and desirably a small dielectric loss tangent. Conventionally, a laminated plate containing polyphenylene oxide is used for such an application. In order to shorten the circuit size, a material having a large dielectric constant and a low dielectric loss tangent is required, and a polyphenylene oxide-based laminate containing an inorganic filler having a large dielectric constant is used. It has started to be done. As a method for producing such a laminated plate, a transparent resin liquid prepared by dissolving a resin component such as polyphenylene oxide in a solvent such as trichloroethylene is prepared, and then a varnish in which an inorganic filler is dispersed in the transparent resin liquid is prepared. A general method was to prepare a resin composition sheet by removing the solvent from the varnish, and heat-laminating and molding the resin composition sheet.

However, the solvent for forming a transparent resin liquid is greatly limited in its choice in terms of solubility of resin components such as polyphenylene oxide, and is not preferable in view of environmental problems. Halogen-based solvents such as trichloroethylene are used, and a method for producing a laminate having excellent performance such as dielectric properties without using the halogen-based solvent is required.

Therefore, a method of producing a prepreg by heating and holding a resin solution, as described in, for example, Japanese Patent Publication No. 63-39404, is considered as a method of using a solvent other than a halogen-based solvent. However, heating and holding requires complicated equipment, and the resin liquid heated and held has problems in terms of significant changes in viscosity over time, handling, work safety, environmental issues, etc. It is desired to develop a manufacturing method that does not make it necessary to heat and hold the material.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, in which a varnish containing a resin component containing polyphenylene oxide, an inorganic filler, and a solvent is prepared. , A method for producing a laminate by heating and laminating a resin composition sheet obtained by removing the solvent from this varnish, wherein a solvent other than a halogen-based solvent can be used as a solvent for the varnish, and the varnish It is an object of the present invention to provide a new method for producing a laminated plate having excellent performance, without making it necessary to heat and hold.

[0007]

A method for producing a laminated board of the invention according to claim 1 comprises a resin component containing polyphenylene oxide, a resin (a) having a crosslinkability and a crosslinking auxiliary agent (b) below. In the method for producing a laminated plate, the inorganic filler and a varnish containing a non-halogenated solvent are prepared, and the resin composition sheet obtained by removing the solvent from this varnish is then laminated by heating. The solvent is once heated to 35 ° C. or higher and mixed, then cooled to form an opaque dispersion liquid of a resin component, and then a varnish obtained by adding the inorganic filler to the dispersion liquid of the resin component is added. It is characterized by using. (A) At least one selected from the group consisting of 1,2-polybutadiene, 1,4-polybutadiene, styrene-butadiene copolymer, modified 1,2-polybutadiene and rubbers. (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.

According to a second aspect of the present invention, there is provided a method for producing a laminated plate according to the first aspect, wherein an inorganic filler is added to the dispersion liquid of the resin component, and then a non-halogen solvent is added. Is characterized by.

A method for manufacturing a laminated board according to a third aspect of the present invention is the method according to the first or second aspect, wherein the inorganic filler is a titanium dioxide-based ceramic, a barium titanate-based ceramic, or a lead titanate-based ceramic. At least one selected from the group consisting of ceramics, strontium titanate-based ceramics, calcium titanate-based ceramics, bismuth titanate-based ceramics, magnesium titanate-based ceramics, and lead zirconate-based ceramics. .

Hereinafter, the present invention will be described in detail. The polyphenylene oxide (hereinafter referred to as PPO) used in the present invention is represented by the following general formula 1, for example.

[0011]

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In the above general formula 1, R represents hydrogen or a hydrocarbon group having 1 to 3 carbon atoms, and each R may be the same or different. Further, n is a positive number indicating the number of repetitions.

An example of PPO is poly (2,6-dimethyl-1,4-phenylene oxide). Such PPO can be synthesized, for example, by the method disclosed in USP 4059568. Although not particularly limited, for example, the molecular weight (M _W ) is 5
0,000, polymers of M _W / M _n = 4.2 are preferably used.

As the crosslinkable resin used in the present invention, the above-mentioned (a) is used, and as the crosslinking aid, the above-mentioned (b) is used. In addition, it is preferable to use triallyl cyanurate or triallyl isocyanurate in the above (b) as a cross-linking aid, since it has good compatibility with PPO and is excellent in film-forming property, cross-linking property, heat resistance and dielectric properties. So good.

The mixing ratio of the above raw materials is not particularly limited, but the ratio of 5 to 60% by weight of the resin having crosslinkability and 1 to 50% by weight of the crosslinking aid with respect to 20 to 90% by weight of PPO. Preferably. In addition, although not particularly limited, 2 parts of the resin having crosslinkability is added to 1 part by weight of the crosslinking aid.
It is preferably used in a proportion of 0 parts by weight or less.

In addition to the above, the resin component of the present invention preferably contains an initiator. As the initiator, dicumyl peroxide, tert-butyl cumyl peroxide, di-
tert-Butyl peroxide, 2.5-dimethyl-2.5
-Di-tert-butylperoxyhexyne-3, 2.5-
Dimethyl-2,5-di-tert-butylperoxyhexane, α · α'-bis (tert-butylperoxy-m-isopropyl) benzene [1.4 (or 1.3) -bis (tert-butylperoxy) Oxyisopropyl) benzene] and the like. In addition, the initiator is not a peroxide, but is a commercially available initiator “Nippon Yushi Co., Ltd.” under the trade name “Biscumyl” (1 min half temperature 330
C.) can also be used.

The non-halogenated solvent used in the present invention is a solvent which can be removed by means such as heating. In particular,
Although it is not particularly limited, a solvent containing at least one selected from the group consisting of benzene, toluene, xylene, ketones and alcohols has no adverse effect on the uniformity of the varnish and on the environment. It is desirable in few points.

In the present invention, the resin component and the halogen-free solvent are once heated to 35 ° C. or higher and mixed, and then cooled to obtain an opaque dispersion liquid of the resin component. In this way, after mixing the resin component and the non-halogenated solvent, the mixture is heated once at 35 ° C. or more and mixed in a state where the solubility of the resin component is increased, and then cooled to obtain a uniform dispersion state. To get the liquid
It is important in the present invention. In the method in which the resin component and the non-halogenated solvent are simply mixed and mixed to form an opaque dispersion without the step of heating to 35 ° C. or more, PPO and the above (a) are added to the non-halogenated solvent. Since the solubility of the resin having cross-linking property is poor, the dispersion of the resin component becomes non-uniform, and therefore the appearance (surface condition) of the resin composition sheet obtained by removing the solvent from the varnish becomes very poor. However, there arises a problem that the uniformity of the performance of the finally obtained laminated plate cannot be ensured. Further, the cooling operation is preferable from the viewpoint of handleability of the dispersion liquid and work safety, and the cooling is preferably performed to room temperature of about 30 ° C. or lower from the viewpoint of handleability of the dispersion liquid.

In the present invention, an inorganic filler is added to and dispersed in the dispersion liquid of the resin component obtained above. It is important in the present invention to prepare the dispersion liquid of the resin component and then add the inorganic filler to the dispersion liquid.
When PO, a resin (a) having crosslinkability, a crosslinking aid (b), an inorganic filler and a non-halogen-based solvent are blended at one time to make a varnish, a resin component such as PPO is obtained. The inorganic filler forms lumps and becomes a liquid in which the dispersion state is extremely non-uniform, which makes the appearance (surface state) of the resin composition sheet obtained by removing the solvent from the varnish extremely poor, and finally There arises a problem that it is not possible to ensure the uniformity of performance of the obtained laminated plate.

The inorganic filler to be used in the present invention is not particularly limited, but titanium dioxide type ceramics, barium titanate type ceramics, lead titanate type ceramics, strontium titanate type inorganic fillers are used because of their high dielectric constant. At least one selected from the group consisting of ceramics, calcium titanate-based ceramics, bismuth titanate-based ceramics, magnesium titanate-based ceramics, and lead zirconate-based ceramics is desirable. In addition, you may combine these 2 or more types. Also,
It is also possible to add a coupling agent to the varnish to improve the adhesion on the laminate.

The concentration of the dispersion liquid of the resin component at the time of adding the inorganic filler to the dispersion liquid of the resin component is set higher than the concentration of the resin component in the varnish to be finally obtained, and the inorganic filler is added. After that, if a non-halogen solvent is further added to adjust the concentration to a predetermined value, the total dispersion time can be shortened, which is desirable. That is, according to the method in which a so-called high-concentration masterbatch is first prepared, and then a solvent is added to adjust the concentration to a predetermined concentration, a uniform dispersion state is easily obtained, so that the total dispersion time can be shortened. Becomes

In the present invention, the solvent is removed from the varnish to obtain a resin composition sheet such as a film or prepreg. When the resin composition sheet is a film, it can be produced, for example, by a casting method, and when it is a prepreg, it can be produced, for example, by an impregnation method.

In the casting method, a varnish is applied to a film for casting to have a thickness of 5 to 700 μm and then heated to remove the solvent to obtain a resin composition sheet (film). The casting film is preferably a polyester film, a polyimide film, or the like, which is insoluble in the solvent in the varnish and has been subjected to a release treatment. In this way, a resin composition sheet having a high resin content can be produced without using a substrate such as glass cloth.

In the impregnation method, the base material is dipped in the varnish to impregnate the base material with the varnish, and then heated (dried) to obtain a prepreg in which the resin composition is attached to the base material. The resin content of this prepreg is not particularly limited, but is 30 to
60% by weight is preferable for obtaining a laminate having good performance. The base material is not particularly limited, but cloth, matte or non-woven fabric, or paper such as kraft paper and linter paper using fibers such as glass fiber, aramid fiber, polyester fiber and nylon fiber can be used.

A predetermined number of the resin composition sheets obtained as described above are combined, and if necessary, a metal foil is also combined and laminated, and the resin is melted and crosslinked by heating and pressing to firmly bond. A laminated plate that is bonded and integrated is obtained. The resin composition sheet may be laminated by combining a film and a prepreg. Although the cross-linking reaction is carried out by heating in this lamination molding step, this cross-linking reaction may be carried out by a method such as UV irradiation.

Examples of the metal foil used in the present invention include copper foil and aluminum foil. The heating and pressing conditions (molding conditions) may be selected as necessary, but since the thermal crosslinking reaction of the resin depends on the reaction temperature of the initiator used, etc., heating depending on the type of initiator Choose a temperature. As an example of specific molding conditions, a temperature of 150 to
300 ° C., pressure 20 to 70 kg / cm ² , molding time 10
It is about 60 minutes. Alternatively, a predetermined number of resin composition sheets may be combined and heat-laminated in advance, and then a metal foil may be placed on one side or both sides of the obtained laminate, and heat-pressed again.

The laminated board thus obtained is made of PPO.
The characteristics are not impaired, high-frequency characteristics such as dielectric characteristics are excellent, and heat resistance is also excellent. Also,
The manufacturing operation is also simple.

[0028]

EXAMPLES The present invention will be described below based on Examples and Comparative Examples.

In the following Examples and Comparative Examples, raw materials having the types and blending amounts (parts by weight) shown in Tables 1 and 2 were used.
For each raw material, the PPO, molecular weight (M _W) is
54,000 poly (2,6-dimethyl-1,4-phenylene oxide, manufactured by Japan GE Plastics Co., Ltd.) was used, and a styrene butadiene copolymer (SBS) was used as a resin having crosslinkability. Triallyl isocyanurate (TAIC) is used as a cross-linking aid, dicumyl peroxide (DCP) is used as an initiator,
Toluene was used as the non-halogen solvent. Titanium dioxide (TiO ₂ ) or barium titanate (BaTiO ₃ ) was used as the inorganic filler. And SBS is Asaprene manufactured by Asahi Kasei Co., Ltd., TAIC is manufactured by Nippon Kasei Co., Ltd., titanium dioxide is Fuji Titanium Industry Co., Ltd. product number TR-840, and barium titanate is Fuji Titanium Industry Co., Ltd. The product number N5500 manufactured by Co., Ltd. was used.

(Example 1) PPO, SBS, TAIC,
DCP and toluene were added to the separable flask in the blending amounts (parts by weight) shown in Table 1, and heated to 80 ° C. in an oil bath while stirring. After stirring at 80 ° C for 2 hours, the mixture was air-cooled to 25 ° C to obtain an opaque resin component dispersion.
Titanium dioxide (TiO ₂ ) which is an inorganic filler was added to the dispersion liquid of this resin component in an amount as shown in Table 1 (parts by weight), and the mixture was stirred with a disper for 5 minutes and then with a basket mill for 1 hour to obtain a uniform mixture. A varnish in a highly dispersed state was obtained. A glass cloth made of E glass having a thickness of 0.1 mm was impregnated with this varnish and then dried at 120 ° C. for 2 minutes to remove the solvent, to obtain a prepreg having a resin content of 66%. The appearance of the obtained prepreg was good. Four prepregs were laminated, copper foil with a thickness of 18 μm was placed on both sides of the prepreg, and the prepreg was laminated on the both sides, and then the temperature was 210 ° C. and the pressure was 30 kg / c.
It was pressed at m ² for 60 minutes to obtain a double-sided copper-clad laminate.

(Example 2) PPO, SBS, TAIC,
DCP and toluene were added to the separable flask only in the blending amounts (parts by weight) shown in Table 1 (toluene was only 190 parts by weight) and heated to 80 ° C. in an oil bath while stirring. After stirring at 80 ° C for 2 hours, air cool to 25 ° C,
An opaque resin component dispersion was obtained. Titanium dioxide (TiO ₂ ) which is an inorganic filler is added to the dispersion liquid of this resin component as shown in Table 1.
The compounding amount (part by weight) shown in 1 was added, and the mixture was stirred with a disper for 5 minutes and then with a basket mill for 1 hour. Next, 48 parts by weight of toluene was additionally added, and the mixture was stirred with a disper for 5 minutes to obtain a varnish in a uniformly dispersed state. A glass cloth made of E glass having a thickness of 0.1 mm was impregnated with this varnish and then dried at 120 ° C. for 2 minutes to remove the solvent, to obtain a prepreg having a resin content of 66%. The appearance of the obtained prepreg was good. Four prepregs were laminated, copper foil with a thickness of 18 μm was placed on both sides of the prepreg, and the prepreg was laminated on the both sides, and then the temperature was 210 ° C. and the pressure was 30 kg / c.
It was pressed at m ² for 60 minutes to obtain a double-sided copper-clad laminate.

Example 3 A varnish, a prepreg and a double-sided copper-clad laminate were prepared in the same manner as in Example 1 except that 200 parts by weight of barium titanate (BaTiO ₃ ) was blended as an inorganic filler. did. The obtained varnish was in a uniformly dispersed state, and the appearance of the obtained prepreg was good.

(Comparative Example 1) PPO, SBS, TAIC,
DCP and toluene were added to the separable flask in the blending amounts (parts by weight) shown in Table 1, and heated to 80 ° C. in an oil bath while stirring. After stirring at 80 ° C. for 2 hours, the mixture was air-cooled to 25 ° C. to obtain an opaque resin component dispersion, and this dispersion was used as a varnish. The resulting varnish was in a uniformly dispersed state. A glass cloth made of E glass having a thickness of 0.1 mm was impregnated with this varnish containing no filler, and then dried at 130 ° C. for 4 minutes to remove the solvent, and a prepreg having a resin content of 50%. Got The appearance of the obtained prepreg is good. Four prepregs are laminated, copper foil with a thickness of 18 μm is arranged on both sides of the prepreg, and the prepreg is laminated on the both surfaces, and then the temperature is 210 ° C. and the pressure is 30 k.
A double-sided copper-clad laminate was obtained by pressing at 60 g / cm ² for 60 minutes.

(Comparative Example 2) PPO, SBS, TAIC,
DCP and toluene were added to the separable flask in the compounding amounts (parts by weight) shown in Table 1 and stirred at room temperature for 2 hours without heating to obtain an opaque resin component dispersion. The dispersion liquid of this resin component contains titanium dioxide (TiO 2) which is an inorganic filler.
₂ ) was added only in the blending amount (parts by weight) shown in Table 1, stirred with a disper for 5 minutes and then with a basket mill for 1 hour to obtain a varnish. This varnish showed a non-uniform dispersion state.
Impregnate a glass cloth made of glass, then 120 ° C
And dried for 2 minutes to remove the solvent to obtain a prepreg having a resin content of 66%. The appearance of the obtained prepreg was very poor and the resin unevenness was remarkable. If this goes on,
Since it was judged that a laminated plate with uniform performance could not be obtained, no laminated plate was prepared.

With respect to the double-sided copper-clad laminates obtained in Examples 1 to 3 and Comparative Example 1, the copper foil peeling strength, solder heat resistance, dielectric constant and dielectric loss tangent were measured and obtained. The results are shown in Tables 1 and 2. The copper foil peeling strength and solder heat resistance are tested according to JIS standard C6481.
Also, the test method of dielectric constant and dielectric loss tangent is MIL
Performed according to the standard. The evaluation results of the appearance of the prepreg are also shown in Tables 1 and 2.

From the results shown in Tables 1 and 2, the appearance of the prepregs obtained in the examples of the present invention is excellent, and the copper foil peeling strength and solder heat resistance, which are important performances as a laminate, are also excellent. Moreover, it is understood that the dielectric constant can be increased by mixing the filler. Further, since the laminated plate obtained in Comparative Example 1 did not contain the filler, the dielectric constant thereof was a low value.

[0037]

[Table 1]

[0038]

[Table 2]

[0039]

According to the method for producing a laminated board of claims 1 to 3, it is not necessary to use a solvent other than a halogen-based solvent as a solvent for forming a varnish and to keep the varnish heated. Since a varnish in a uniformly dispersed state can be obtained, a resin composition sheet having a good appearance can be manufactured. Therefore, according to the method for producing a laminated board of claims 1 to 3, the non-halogenated solvent is used, the dielectric constant is controlled by the selection of the inorganic filler, and the copper foil peeling strength and solder heat resistance are Therefore, it becomes possible to easily manufacture a laminated plate having excellent properties.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C08K 5/10 KDB C08K 5/10 KDB C08L 63/00 NJQ C08L 63/00 NJQ 71/12 LQP 71 / 12 LQP // H01B 3/18 H01B 3/18 H05K 1/03 610 7511-4E H05K 1/03 610R (72) Inventor Isao Hirata 1048 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Works Co., Ltd.

Claims (3)

[Claims] 1. A varnish containing a resin component containing polyphenylene oxide, a crosslinkable resin (a) below and a crosslinking aid (b) below, an inorganic filler, and a non-halogen solvent is prepared. Then, in the method for producing a laminated plate in which a resin composition sheet obtained by removing the solvent from this varnish is heated and laminated, the resin component and the solvent are once heated to 35 ° C. or higher and mixed, and then cooled. Then, an opaque resin component dispersion liquid is prepared, and then a varnish obtained by adding the inorganic filler to the resin component dispersion liquid is used. (A) At least one selected from the group consisting of 1,2-polybutadiene, 1,4-polybutadiene, styrene-butadiene copolymer, modified 1,2-polybutadiene and rubbers. (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. The method for producing a laminated board according to claim 1, wherein after adding the inorganic filler to the dispersion liquid of the resin component, a non-halogen solvent is further added. 3. The inorganic filler is titanium dioxide ceramic, barium titanate ceramic, lead titanate ceramic, strontium titanate ceramic, calcium titanate ceramic, bismuth titanate ceramic, magnesium titanate ceramic. And at least one selected from the group consisting of lead zirconate-based ceramics, and the method for producing a laminated board according to claim 1 or 2, wherein