JP2003213021A - Prepreg, metal-clad laminated plate and printed wiring plate using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a prepreg that has excellent appearance with the occurrence of pin holes suppressed and shows excellent drilling processability, when the prepregs are laminated, and provide metal-clad laminated plates and printed wiring plate using the same. <P>SOLUTION: The backing materials (substrates) are impregnated with a resin composition to prepare the prepregs. In this case, the substrate is glass fiber-woven fabric having the air permeability of 1-65 cm<SP>3</SP>/cm<SP>2</SP>/sec and the thickness of 20-100 μm, the resin composition includes inorganic filler and silicone polymer wherein the amount of the inorganic filler is ≥25 vol.% on the basis of the total solid components. The resultant prepregs or their laminates are clad with metal foil on one face or both faces. Finally, the printed wired boards are obtained by printing the wiring on the metal-clad laminated boards. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a prepreg, and a metal-clad laminate and a printed wiring board using the prepreg.

[0002]

2. Description of the Related Art In recent years, electronic devices have been rapidly becoming higher in density, smaller in size, and lighter in weight. Therefore, the demand for thin prepregs and metal-clad laminates has increased, and they have been used as base materials for prepregs. A thin woven cloth is used. Further, since it is also required to improve the elastic modulus of the substrate, it has been attempted to bring out its characteristics by using an inorganic filler.
On the other hand, in wiring boards that are becoming smaller and lighter, through-hole through holes and via holes also have smaller diameters, increasing the demand for fine processing, and drilling with a diameter of 0.1 to 0.15 mm is performed. It is like this.

[0003]

However, when it is attempted to obtain a prepreg by impregnating a thin glass woven cloth having a thickness of 100 μm or less with a varnish containing a large amount of an inorganic filler, the gap in the glass woven cloth is large. As a result, there is a problem that many pinholes are generated in the prepreg. Due to this pinhole in the prepreg, air bubbles may remain after press molding, which may cause insulation failure in a printed wiring board using this. Further, in the conventional glass woven fabric, when the air permeability is high, the overlapping portion and the non-overlapping portion of the glass woven fiber bundle occur, and a difference in prepreg strength occurs, which causes early damage of the drill blade in the laminated plate. There was also a problem. Therefore, the present invention is a prepreg obtained by impregnating a thin glass woven cloth with a varnish containing an inorganic filler, the occurrence of pinholes is suppressed, and the appearance is also good, and drilling when formed into a laminated plate An object is to provide a prepreg having excellent properties, and a metal-clad laminate and a printed wiring board using the prepreg.

[0004]

The prepreg according to the present invention is a prepreg obtained by impregnating a base material with a resin composition, wherein the base material has an air permeability of 1 to 65 cm ³ / cm ² / se.
c, a glass woven fabric having a thickness of 20 to 100 μm, wherein the resin composition contains an inorganic filler and a silicone polymer, and the compounding amount of the inorganic filler is 25% by volume or more based on the total solid content of the resin composition. It is characterized by being. The metal-clad laminate according to the present invention is formed by forming a metal layer on both sides or one side of the prepreg or the laminate thereof according to the present invention. The printed wiring board according to the present invention is obtained by subjecting the metal-clad laminate according to the present invention to circuit processing.

In the prepreg according to the present invention, the glass woven fabric as the base material has an air permeability of 1 to 65 cm ³ / cm ² /
sec, the resin composition for impregnation contains an inorganic filler and a silicone polymer, and the amount of the inorganic filler is 25% by volume or more based on the total solid content of the resin composition.
Even when a thin glass woven cloth having a thickness of 20 to 100 μm is impregnated with a varnish containing an inorganic filler, the occurrence of pinholes is suppressed and the prepreg has a good appearance. Therefore, using this, it is possible to provide a metal-clad laminate and a printed wiring board in which troubles such as poor insulation do not easily occur. Furthermore, the air permeability of the glass woven fabric is 65 cm ³ / cm
Since it is ² / sec or less, the cross strength is made uniform,
It is possible to provide a metal-clad laminate and a printed wiring board which are less likely to cause early damage to the drill blade and have good drilling workability.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION A glass woven cloth is used as a base material of a prepreg according to the present invention. Generally, a glass woven fabric is a fabric in which glass fiber yarns are woven in the lengthwise and widthwise directions. In the present invention, the air permeability is 1 to 65 cm ³ / cm ² / s.
A woven glass fabric that is ec is used. A glass woven fabric having such air permeability can be obtained, for example, by subjecting both warp yarns and weft yarns to a high degree of pre-spreading treatment. Further, the woven glass fabric after being woven can be further subjected to an opening process. The degree of opening may be arbitrarily controlled according to the required air permeability. If the air permeability is higher than 65 cm ³ / cm ² / sec,
The frequency of pinholes may increase.

In the present invention, the air permeability of the glass woven fabric is regulated, and the glass fiber yarn and / or the glass woven fabric is subjected to a high degree of necessary fiber-spreading treatment, so that the same glass as the conventional glass woven fabric is obtained. Even if the fiber yarn is used, the thickness of the woven fabric can be kept small. Further, as compared with the conventional glass woven fabric, the glass fiber yarns are spatially expanded by the fiber opening treatment and the void space is greatly suppressed, so that the impregnation property of the resin composition into the glass woven fabric is improved and the resin repelling is prevented. Can be significantly reduced. As a result, it is possible to obtain a prepreg having a good appearance without pinholes. In order to obtain better drilling workability, the air permeability of the glass woven fabric is 1 to 12 cm ³ / cm ² / s in order to make the prepreg strength uniform.
ec is more desirable.

The glass woven fabric has a thickness of 20 to 100 μm. When the thickness of the glass woven fabric exceeds 100 μm, the air permeability is generally 65 cm ³ / cm ² / sec or less,
Since there is no difference in air permeability between a general glass woven fabric and a glass woven fabric that has been subjected to a highly opened treatment, it is difficult to recognize the superiority of the present invention. Further, a highly woven glass woven fabric having a thickness of less than 20 μm may be difficult to handle. Further, when the number of glass fiber threads in the glass woven fabric is close to the same number in the longitudinal and lateral directions, the air permeability is easily regulated, and the fiber yarn density in the glass woven fabric is made uniform, so that the prepreg and the metal foil are made uniform. The strength of the stretched laminated plate is made uniform and drill workability is improved. Specifically, it is most preferable that the ratio of the number of warp threads and the number of weft threads in the woven glass fabric is 1 (the number of warp threads and weft threads is equal). The weaving method of the glass woven fabric is not particularly limited, and any weaving method can be used.

Next, the resin composition impregnated into the woven glass cloth contains an inorganic filler and a silicone polymer. The inorganic filler is not particularly limited, and for example, boron, carbon, clay, glass, calcium carbonate, talc, alumina, silica, mica, titanium oxide,
Aluminum carbonate, aluminum hydroxide, magnesium silicate, aluminum silicate, aluminum borate, silicon carbide and the like can be used alone or in combination of two or more kinds. Among them, it is preferable to use at least one of aluminum hydroxide, silica and magnesium silicate, because the appearance of flame retardance and the improvement of drill workability can be achieved. Further, their shape is not particularly limited, and beads, powders, fibers, crushed products, whiskers, and flakes can be used.

The blending amount of the inorganic filler is not particularly limited as long as it is 25% by volume or more based on the total solid content of the resin composition, but is 65% by volume or less from the viewpoint of appearance and handleability. Preferably there is. If it exceeds this, the appearance of the prepreg may be deteriorated due to thickening of the resin composition and the handling thereof may become difficult. When the compounding amount of the inorganic filler is less than 25% by volume, the viscosity of the resin composition becomes low and the dispersibility of the inorganic filler decreases due to no shearing force, which is preferable in that the appearance is deteriorated. Absent.

Next, the silicone polymer used in the resin composition is blended for the purpose of improving the dispersibility of the inorganic filler in the resin. A three-dimensionally crosslinked silicone polymer is used and is produced by hydrolyzing and polycondensing a silane compound. The silane compound is not particularly limited, but it is preferable to use a 2- to 4-functional silane compound. Here, the functionality in the silane compound means having a condensation-reactive functional group. Specifically, tetrafunctional silane compounds such as tetraalkoxysilane, monoalkyltrialkoxysilane, phenyltrialkoxysilane, monoalkyltriacyloxysilane, trifunctional silane compounds such as monoalkyltrihalogenosilane, and dialkyldialkoxysilane. , Dialkyldiacyloxysilane, dialkyldihalogenosilane, and other bifunctional silane compounds. These are used alone or in combination of two or more. The blending amount of the silicone polymer is preferably 1% by weight or more of the blending weight of the inorganic filler from the viewpoint of ensuring the dispersibility of the inorganic filler, and the inorganic filler from the viewpoint of adhesive strength with the metal foil. It is preferably 10% by weight or less of the compounding weight of.

The base resin of the resin composition is not particularly limited, but a thermosetting resin is preferably used, and a thermoplastic resin having high heat resistance can also be used. Specifically, for example, epoxy resin, polyimide resin, triazine resin, melamine resin, phenol resin and the like can be preferably used. Two or more kinds of these resins may be used in combination, and various curing agents and curing accelerators may be added as necessary. Note that these additives may be mixed as a solvent or a solution.

As the curing agent, various conventionally known ones can be used. For example, when an epoxy resin is used as a resin, amine compounds such as dicyandiamide, diaminodiphenylmethane, diaminodiphenylsulfone, phthalic anhydride, and anhydride. Examples thereof include acid anhydride compounds such as pyromellitic acid, and polyfunctional phenol compounds such as phenol novolac resins and cresol novolac resins. Two or more kinds of these curing agents may be used in combination. The type of curing accelerator is not particularly limited, and examples thereof include imidazole compounds, organic phosphorus compounds, secondary amines, tertiary amines, quaternary ammonium salts, and the like, and two or more types are used in combination. You may. The compounding amount of the curing accelerator is also not particularly limited, but it is preferable to use about 0.01 to 10.0 parts by weight with respect to 100 parts by weight of the resin as the main material.

The resin composition containing the above components is preferably diluted with a solvent to form a varnish for use. The type of solvent is not particularly limited, and examples thereof include alcohol solvents such as methanol and ethanol, ether solvents such as ethylene glycol monomethyl ether, ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone, and N, N. -Amide solvents such as dimethylformamide, toluene, aromatic hydrocarbon solvents such as xylene, ester solvents such as ethyl acetate, nitrile solvents such as butyronitrile,
These can be used alone or in combination of two or more. The solid content concentration of the varnish may be appropriately set depending on the resin composition, the type and blending amount of the inorganic filler, etc., but is generally preferably in the range of 50 to 80% by weight.

The prepreg according to the present invention is obtained by impregnating the above-mentioned glass woven fabric with the above-mentioned varnished resin composition, if necessary, and then drying. Drying is 20 to 20
It is preferable to perform it while heating to about 0 ° C. The impregnated amount of the varnish is not particularly limited, but it is preferable that the amount of the varnish attached containing the inorganic filler be about 35 to 70% by weight.

The metal-clad laminate according to the present invention comprises a prepreg according to the present invention or a laminate in which a plurality of the prepregs are laminated, and a metal layer which is a wiring conductor is formed on both sides or one side of the laminate. The metal layer can be formed by stacking an arbitrary metal foil such as a copper foil or an aluminum foil on a prepreg and heat-pressing. The temperature at that time is 170 ° C to 24 ° C.
It is preferable that the temperature is about 0 ° C. and the pressure is about 1 to 8 MPa.

The printed wiring board according to the present invention is obtained by subjecting the metal-clad laminate according to the present invention to circuit processing. The circuit processing on the metal layer can be performed by a known method. In addition, this one-sided or double-sided printed wiring board is used as an inner layer circuit board, prepregs are arranged on both sides or one side of the inner layer circuit board, and a metal layer is further formed and press-molded, and then interlayer connection or outer layer circuit formation is performed to form a multilayer A printed wiring board can be manufactured.

[0018]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples without departing from the technical idea of the present invention.

Example 1 A brominated bisphenol A was placed in a glass flask equipped with a stirrer, a condenser and a thermometer.
Type epoxy resin (epoxy equivalent: 530, manufactured by Tohto Kasei Co., Ltd., YDB-500) 100 parts by weight, dicyandiamide 4 parts by weight, 2-ethyl-4-methylimidazole 0.5 parts by weight, silicone polymer (tetramethoxysilane, Weight ratio of methanol, acetic acid, and distilled water is 80:
1 part by weight, 65 parts by weight of silica, and 65 parts by weight of aluminum hydroxide were added, dissolved in methyl ethyl ketone, and the mixture was allowed to stand at room temperature for about 2 hours. And stir to obtain a solid content of 70
A wt% resin composition varnish was prepared. Here, the ratio of the inorganic filler to the total solid content of the resin composition is about 40.
It was% by volume. The obtained varnish was made to have an air permeability of 4.4 cm.
³ / cm ² / sec, 80 μm thick glass woven cloth (length 5
9 pieces × 46 pieces in width) and then dried at 150 ° C. for 5 minutes to obtain a prepreg having an inorganic filler-containing varnish of 55% by weight. 4 sheets of this prepreg are laminated, 12 μm copper foil is laminated on both sides of the prepreg, 180 ° C., 60 minutes, 4.0M
A copper clad laminate was prepared by heating and pressing under Pa press conditions.

[Example 2] Air permeability 1.85 cm ³ / cm
^A prepreg and a copper clad laminate were obtained in the same manner as in Example 1 except that a glass woven fabric (60 lengths × 46 widths) having a thickness of ² / sec and a thickness of 78 μm was used.

[Example 3] Air permeability 7.47 cm ³ / cm
^A prepreg and a copper clad laminate were obtained in the same manner as in Example 1 except that a glass woven cloth (55 length × 55 width) having a thickness of 42 μm / ² / sec was used.

[Comparative Example 1] Air permeability 14.5 cm ³ / cm
^A prepreg and a copper clad laminate were obtained in the same manner as in Example 1 except that a glass woven fabric (60 lengths × 46 widths) having a thickness of 79 μm / ² / sec was used.

[Comparative Example 2] Air permeability 94 cm ³ / cm ² /
sec, 49 μm thick glass woven cloth (60 length x 47 width)
A prepreg and a copper-clad laminate were obtained in the same manner as in Example 1 except that the present) was used.

[Comparative Example 3] A prepreg and a copper clad laminate were obtained in the same manner as in Example 1 except that the filling rate of the inorganic filler was set to 20% by volume.

[Comparative Example 4] A prepreg and a copper clad laminate were obtained in the same manner as in Example 1 except that the silicone polymer was not used.

The appearance of the prepregs obtained in the above Examples and Comparative Examples, the number of pinholes per 1 m ² , and the drilling workability of the copper clad laminate were evaluated. The drilling conditions are as follows: drill diameter (diameter) 0.1 mm, rotation speed 20.
20,000 rpm, feed rate 2.0 m / min, number of stacked sheets 4, entry board 150 μm, aluminum plate.

The results obtained are shown in Table 1.

[0028]

[Table 1] The prepreg of the example had fewer pinholes and a better appearance than the prepreg of the comparative example, and the drill workability of the copper-clad laminate was excellent. On the other hand, in the prepreg of the comparative example,
It was found that the breakage of the drill occurred in less than 1000 hits in each case, and the early damage of the drill was a problem.

[0029]

The prepreg of the present invention has a good appearance and can suppress the number of pinholes generated. Further, the metal-clad laminate obtained by laminating the prepreg of the present invention,
Excellent drilling workability.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H05K 1/03 610 H05K 1/03 610R 610T F term (reference) 4F072 AB09 AB28 AD47 AF01 AG03 4F100 AA00A AA03A AA03H AA19A AA19H AA20A AA20H AB01B AB01C AB17 AB33 AG00A AK52A AK53 BA01 BA02 BA03 BA06 BA10B BA10C CA23A DG12A DH01A EJ17 EJ42 EJ82A GB43 JA20A JD02A JK14 JL01 YY00A 4J002 CP0161 DE136 DJ006 DJ006

Claims (5)

[Claims] 1. A prepreg obtained by impregnating a base material with a resin composition, wherein the base material has an air permeability of 1 to 65 cm ³ / c.
m ² / sec, a glass woven fabric having a thickness of 20 to 100 μm, the resin composition contains an inorganic filler and a silicone polymer, and the compounding amount of the inorganic filler is 25 with respect to the total solid content of the resin composition. A prepreg characterized by being at least volume%. 2. The prepreg according to claim 1, wherein the ratio of the number of warp threads to the number of weft threads in the woven glass fabric is 1. 3. The inorganic filler is aluminum hydroxide,
The prepreg according to claim 1 or 2, containing at least one selected from the group consisting of silica and magnesium silicate. 4. A metal-clad laminate comprising a prepreg according to any one of claims 1 to 3 or a laminate thereof having a metal layer formed on both sides or one side thereof. 5. A printed wiring board obtained by performing circuit processing on a metal-clad laminate having a metal layer formed on both surfaces or one surface of the prepreg or the laminate thereof according to any one of claims 1 to 3.