JPH0722718A - Epoxy resin composition for printed wiring board, manufacture of prepreg for printed wiring board, and manufacture of composite laminated sheet - Google Patents

Abstract

PURPOSE:To provide a method for manufacturing a composite laminated sheet which can obtain a composite laminated sheet with an improved tracking resistance property and a method for manufacturing the epoxy resin composition for printed wiring board and a prepreg for printed wiring board for printed wiring board used for this method without reducing other characteristics. CONSTITUTION:After varnish consisting of an epoxy resin composition for printed wiring board which is blended with epoxy resin (a), dicyandiamde or polycondensate of bisphenol A and aldehyde (b), inorganic filling agent (c), and metal capturing agent (d) as essential ingredients is dipped to a glass cloth, it is dried to manufacture prepreg for surface cloth. Then, a composite laminated sheet is manufactured with lamination formation by overlapping the prepreg for surface cloth on the double sides of the prepreg for a center layer and the epoxy resin composition for a printed wiring board used for this method and the prepreg for printed wiring board are manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition for printed wiring boards, a method for producing a prepreg for printed wiring boards and a method for producing a composite laminated board.

[0002]

2. Description of the Related Art As electronic devices have become smaller and have higher performance, printed wiring boards mounted therein have higher densities due to higher multi-layers, thinner products, smaller through-hole diameters and smaller hole intervals. Is in progress. Further, printed wiring boards used for consumer equipment are required to have tracking resistance from the viewpoint of ensuring safety. For high-density wiring boards,
Glass / epoxy laminates and composite laminates are often used, and paper / phenolic laminates and composite laminates are often used for consumer use due to price constraints. Therefore, there is an increasing demand for composite laminates with a good balance of properties and price.

A composite laminated plate is constructed by using a glass woven cloth as a surface layer base material and a glass nonwoven fabric as a core material base material, and has been widely used conventionally as an insulating material for a composite laminated board. Epoxy resins include those that are cured with dicyandiamide and those that use polyfunctional phenolic resins as curing agents, but with the dicyandiamide curing system, the resulting laminate has high hygroscopicity, and metal migration (substrate surface circuit and through The metal that forms the conductive circuit in the hole diffuses into the insulating substrate and eventually forms a conductive part in the insulating substrate. A system using a phenolic resin as a curing agent has a low water absorption rate and various properties as a laminated plate are generally good, but it is inferior in tracking resistance. Cormorants problems had been left.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and manufacture of a composite laminate capable of obtaining a composite laminate excellent in tracking resistance without deteriorating other characteristics. An object of the present invention is to provide a method, an epoxy resin composition for a printed wiring board, and a method for producing a prepreg which are preferably used for the production thereof.

[0005]

That is, the epoxy resin composition used in the present invention is (a) epoxy resin, (b)
It is characterized in that dicyandiamide or a polycondensate of bisphenol A and formaldehyde, (c) an inorganic filler and (d) a metal scavenger are added as essential components.

The epoxy resin (a) may be any compound as long as it is a compound having two or more epoxy groups in the molecule, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S. Type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, bisphenol F novolac type epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, glycidyl ester type epoxy resin, glycidyl Amine type epoxy resin, hydantoin type epoxy resin, isocyanurate type epoxy resin, other diglycidyl ether compound of bifunctional phenols,
There are diglycidyl ether compounds of difunctional alcohols and their halides, hydrogenated compounds and the like. The molecular weight of these compounds is not particularly limited. In addition, these compounds can be used in combination with several kinds of compounds.

When sufficient flame retardancy cannot be obtained with the halogenated epoxy resin alone, it is preferable to add a compound generally called a flame retardant such as tetrabromobisphenol A, antimony trioxide, and tetraphenylphosphine.

When an ordinary phenol resin is used as a curing agent for an epoxy resin, the heat discoloration of the cured product is apt to be a problem, but when the polycondensation product of (b) bisphenol A and formaldehyde is used, the heat discoloration property is deteriorated. Be improved.

There is no limitation on the molecular weight of the polycondensate of bisphenol A and formaldehyde of (b), and a bisphenol A monomer may be contained. The blending amount of the component (b) is not particularly limited, but is preferably 1 to 100 parts by weight with respect to 100 parts by weight of the epoxy resin (a). Further, a phenol resin such as a phenol novolac resin may be used in combination within the range that does not impair the effects of the present invention.

The inorganic filler (c) is not particularly limited and includes, for example, aluminum hydroxide, calcium carbonate, alumina, titanium oxide, mica, clay, aluminum carbonate, magnesium silicate, aluminum silicate, antimony trioxide, Silica, short glass fibers, etc. are used. Further, several kinds of these may be used in combination, and the compounding amount thereof is not particularly limited, but the epoxy resin 1 is preferable.
10 to 400 parts by weight are used with respect to 00 parts by weight.

The metal scavenger (d) is an organic compound that acts as a metal ligand and has an effect of suppressing tracking breakdown and conduction breakdown caused by metal migration. Specifically, trithiocyanuric acid, 6-dibutylamino-1,3,5-triazine-
2,4-dithiol, 6-diethylamino-1,3,5
-Triazine-2,4-dithiol, 6-dimethylamino-1,3,5-triazine-2,4-dithiol, 6
-Methoxy-1,3,5-triazine-2,4-dithiol, 6-phenylamino-1,3,5-triazine-
Triazine thiol compound (f) such as 2,4-dithiol, thiazole, 2-aminothiazole, 2-mercaptothiazole, benzothiazole, 2-aminobenzothiazole, 2-mercaptobenzothiazole, 2,
Thiazole compounds (g) such as 2'-dithiobisbenzothiazole and 2-methylthiobenzothiazole, 8-quinolinol, 5-nitroquinolinol-8,7-bis (2
-Ethylhexyl) aminomethylene-8-quinolinol, 7-bis (n-butyl) aminomethylene-8-quinolinol, 7-bis (n-hexyl) aminomethylene-
Oxine compounds (h) such as 8-quinolinol, 1, 2,
3-triazine, 1,2,4-triazine, 1,3,5
-Triazine and their derivatives 2-butylamino-4,6-dimercapto-1,3,5-triazine,
2-Vinyl-4,6-diamino-1,3,5-triazine, 2,4-diamino-6 (2'-methylimidazolyl (1) ') ethyl-1,3,5-triazine / isocyanuric acid adduct Triazine compounds (i) and the like are preferably used.

Several kinds of these metal scavengers may be used in combination, and the compounding amount is preferably 0.1 to 20 parts by weight with respect to 100 parts by weight of the epoxy resin. If it is less than 0.1 parts by weight, the tracking resistance is not improved, and if it exceeds 20 parts by weight, the heat resistance and insulating properties may be deteriorated.

The epoxy resin composition of the present invention preferably contains the reducing agent (e) in order to improve the electric insulation properties. The reducing agent is not particularly limited as long as it is a compound having a reducing action on the conductive circuit metal, that is, through-hole plated copper and copper foil, and a reducing agent such as phenol-based, sulfur-based or phosphorus-based can be used. . In particular,
Phenol-based reducing agents are preferably used because they can improve electrical insulation properties such as metal migration resistance without degrading various properties such as drill workability and heat resistance.

As the phenol-based reducing agent, 1, 2, 3
-Triphenols such as trihydroxybenzene (commonly known as pyrogallol), butylated hydroxyanisole, and 2,4-di-t-butyl-4-ethylphenol;
2'-methylene-bis (4-methyl-6-t-butylphenol), 4,4'-thiobis (3-methyl-6-t)
-Butylphenol) and other bisphenols and 1,
3,5-Trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tetrakis [methylene-3- (3 ', 5'-di-t-butyl-benzene- 4-hydroxyphenyl) propionate] methane, triethylene glycol-bis-3- (3-t-butyl-4-hydroxy-5-methyl-phenyl) propionate, and other high-molecular-weight phenolic compounds.

Examples of the sulfur-based reducing agent include dilauryl thiodipropionate and distearyl thiodipropionate. Examples of phosphorus-based reducing agents include triphenyl phosphite and diphenyl isodecyl phosphite.

These reducing agents may be used in combination of several kinds, and the compounding amount is based on 100 parts by weight of the epoxy resin.
0.1 to 20 parts by weight is preferable. If it is less than 0.1 part by weight, the effect of improving the insulation property is small, and if it exceeds 20 parts by weight, the insulation property and heat resistance may be deteriorated.

The epoxy resin composition of the present invention is used in various forms, but a solvent is often used when coating and impregnating a base material such as glass cloth or glass nonwoven cloth. These solvents include acetone, methyl ethyl ketone, toluene, xylene, methyl isobutyl ketone, ethyl acetate, ethylene glycol monomethyl ether, N, N-dimethylformamide, N, N-dimethylacetamide, methanol and ethanol. You may mix and use it. Also, above
(a), (b), (c) and (d) are essential components,
If necessary, other compounds may be mixed within a range that does not impair the effects of the present invention.

These (a), (b), (c) and (d)
The varnish obtained by mixing (e) a reducing agent and a solvent, if necessary, is preferably 80 to 80
By drying in the range of 200 ° C., a prepreg for a printed wiring board, which is suitable for use as a surface fabric of a composite laminate, can be obtained. The prepreg for the outer cloth is laminated on both sides of the prepreg for the core material, preferably 150 to 190.
It is used for producing a composite laminate by heating and pressing at a temperature of 1.0 to 8.0 MPa. On this occasion,
A metal foil may be arranged on the outer layer surface to form a metal foil-clad laminate.

Drying here means removing the solvent when a solvent is used, and eliminating the fluidity of the resin material impregnated in the substrate at room temperature when the solvent is not used. Say.

[0020]

EXAMPLES The present invention will be described below based on examples, but the present invention is not limited thereto.

Example 1 100 parts by weight of brominated bisphenol A type epoxy resin (epoxy equivalent 530), 4.0 parts by weight of dicyandiamide, 0.5 part by weight of 2-ethyl-4-methylimidazole, 100 parts by weight of aluminum hydroxide, 0.5 parts by weight of pyrogallol and 0.5 parts by weight of trithiocyanuric acid were dissolved in a mixed solvent of methyl ethyl ketone and ethylene glycol monomethyl ether to prepare a varnish having a nonvolatile content of 75% by weight. This varnish was applied to a glass nonwoven fabric (EPM-4060N manufactured by Nippon Vilene Co., Ltd.) with a resin content of 90.0
It was impregnated to 2.0% by weight and dried to obtain a glass nonwoven fabric prepreg for surface cloth.

A varnish having the same composition as that described above except that aluminum hydroxide was not added was used as a glass cloth (manufactured by Nitto Boseki Co., Ltd. W
E-18K-RB84) was impregnated with a resin content of 41.0 ± 3.0% by weight and dried to obtain a glass woven prepreg for a core material.

Glass woven cloth prepregs are laminated on the upper and lower sides of the glass non-woven cloth prepreg for the surface cloth, and an electrolytic copper foil (manufactured by Nippon Denshoku Co., Ltd.) having a thickness of 18 μm is arranged as the outermost layer at 170 ° C./2.
It was heated and pressed at 94 MPa for 70 minutes to obtain a copper-clad laminate having a thickness of 1.6 mm.

Example 2 A copper clad laminate was obtained in the same manner as in Example 1 except that 0.5 part by weight of 8-quinolinol was added instead of tricyanuric acid.

Example 3 Example 1 was repeated except that 0.5 part by weight of triphenyl phosphite was blended in place of pyrogallol.
A copper clad laminate was obtained in the same manner as in.

Comparative Example 1 A composite copper clad laminate was obtained in the same manner as in Example 1 except that tricyanuric acid was not added.

The tracking resistance of the composite copper-clad laminates obtained in Examples 1 to 3 and Comparative Example 1 was evaluated. The results are shown in Table 1.

[0028]

[Table 1] In each of Examples 1 to 3 in which the metal scavenger was mixed, the tracking resistance was better than that of Comparative Example 1.

Example 4 Bisphenol A 1,000 g, 37% formalin 22
0 g and 10 g of oxalic acid were placed in a four-necked flask equipped with a condenser and a stirrer, refluxed for 2 hours to cause a reaction, and then dehydrated and concentrated to obtain a bisphenol A novolak resin [A]. This was used and compounded as follows to obtain a varnish.

Brominated bisphenol A type epoxy resin 1
00 parts by weight (epoxy equivalent 530), bisphenol A
22 parts by weight of novolak resin [A], 0.5 parts by weight of 2-ethyl-4-methylimidazole, 1 part of aluminum hydroxide
00 parts by weight, 0.5 parts by weight of pyrogallol and 0.5 parts by weight of trithiocyanuric acid were dissolved in a mixed solvent of methyl ethyl ketone and ethylene glycol monomethyl ether to prepare a varnish having a nonvolatile content of 75% by weight. This varnish is a glass non-woven fabric (EPM-4060 manufactured by Japan Vilene Co., Ltd.).
N) was impregnated with a resin content of 90.0 ± 2.0% by weight and dried to obtain a glass nonwoven fabric prepreg for a core material.

A varnish having the same composition as that described above except that aluminum hydroxide was not added was used as a glass cloth (manufactured by Nitto Boseki Co., Ltd. W
E-18K-RB84) was impregnated with a resin content of 41.0 ± 3.0% by weight and dried to obtain a glass woven cloth prepreg for surface cloth.

Using the prepreg obtained as described above, a copper clad laminate was obtained in the same manner as in Example 1.

Example 5 A copper clad laminate was obtained in the same manner as in Example 4 except that 0.5 part by weight of 8-quinolinol was added instead of tricyanuric acid.

Example 6 Example 4 was repeated except that 0.5 part by weight of triphenylphosphite was used instead of pyrogallol.
A copper clad laminate was obtained in the same manner as in.

Comparative Example 2 A copper clad laminate was obtained in the same manner as in Example 4 except that tricyanuric acid was not added.

Comparative Example 3 A copper clad laminate was obtained in the same manner as in Example 4 except that pyrogallol was not added.

The composite copper-clad laminates obtained in Examples 4 to 6 and Comparative Examples 2 to 3 were evaluated for tracking resistance and copper migration resistance. The results are shown in Table 2.

[0038]

[Table 2] In Examples 4 to 6 in which the metal scavenger was blended, the tracking resistance was good as compared with Comparative Examples 2 and 3, and the copper migration resistance was good as compared with Comparative Example 3.

Example 7 100 parts by weight of brominated bisphenol A type epoxy resin (epoxy equivalent 530), 4.0 parts by weight of dicyandiamide, 0.5 part by weight of 2-ethyl-4-methylimidazole, 100 parts by weight of aluminum hydroxide, 0.5 parts by weight of pyrogallol and 0.5 parts by weight of trithiocyanuric acid were dissolved in a mixed solvent of methyl ethyl ketone and ethylene glycol monomethyl ether to prepare a varnish having a nonvolatile content of 75% by weight. A glass cloth (WE-18K-RB84 manufactured by Nitto Boseki Co., Ltd.) was impregnated with this varnish so that the resin content was 41.0 ± 3.0% by weight, and dried to obtain a glass woven cloth prepreg for a surface cloth.

A varnish having the same composition as the above except that aluminum hydroxide and trithiocyanuric acid were not blended was made of a glass non-woven fabric (EPM-4060N manufactured by Japan Vilene Co., Ltd.).
It was impregnated with a resin content of 90.0 ± 2.0% by weight and dried to obtain a glass nonwoven fabric prepreg for a core material.

Glass woven cloth prepreg for surface cloth is laminated on the upper and lower sides of the glass nonwoven cloth prepreg for the core material, and the outermost layer has a thickness of 18 μm.
m electrolytic copper foil (manufactured by Nippon Denki Co., Ltd.) is placed at 170 ° C.
The thickness is 1.6m when heated and pressurized at /2.94MPa for 70 minutes.
m composite copper clad laminate was obtained.

Example 8 A copper clad laminate was obtained in the same manner as in Example 7 except that 0.5 part by weight of 8-quinolinol was added instead of tricyanuric acid.

Example 9 Example 7 was repeated except that 0.5 part by weight of triphenyl phosphite was blended in place of pyrogallol.
A copper clad laminate was obtained in the same manner as in.

Comparative Example 4 A composite copper clad laminate was obtained in the same manner as in Example 7 except that tricyanuric acid was not added.

The composite copper clad laminates obtained in Examples 7 to 9 and Comparative Example 4 were evaluated for tracking resistance. The results are shown in Table 3.

[0046]

[Table 3] In each of Examples 7 to 9 in which the metal scavenger was mixed, the tracking resistance was good as compared with Comparative Example 4.

Example 10 100 parts by weight of brominated bisphenol A type epoxy resin (epoxy equivalent 530), 22 parts by weight of bisphenol A novolac resin [A], 0.5 parts by weight of 2-ethyl-4-methylimidazole, aluminum hydroxide 100 parts by weight, 0.5 parts by weight of pyrogallol and 0.5 parts by weight of trithiocyanuric acid were dissolved in a mixed solvent of methyl ethyl ketone and ethylene glycol monomethyl ether to give a nonvolatile content of 7 parts.
A 5% by weight varnish was prepared. A glass cloth (WE-18K-RB84 manufactured by Nitto Boseki Co., Ltd.) was impregnated with this varnish so that the resin content was 41.0 ± 3.0% by weight, and dried to obtain a glass woven cloth prepreg for a surface cloth.

A varnish having the same composition as described above except that aluminum hydroxide and trithiocyanuric acid were not blended was made of a glass nonwoven fabric (EPM-4060N manufactured by Nippon Vilene Co., Ltd.).
It was impregnated with a resin content of 90.0 ± 2.0% by weight and dried to obtain a glass nonwoven fabric prepreg for a core material.

Using the prepreg obtained above, a copper clad laminate was obtained in the same manner as in Example 1.

Example 11 A copper clad laminate was obtained in the same manner as in Example 10 except that 0.5 part by weight of 8-quinolinol was added instead of tricyanuric acid.

Example 12 A copper clad laminate was obtained in the same manner as in Example 10 except that 0.5 part by weight of triphenylphosphite was added instead of pyrogallol.

Comparative Example 5 A copper clad laminate was obtained in the same manner as in Example 10 except that tricyanuric acid was not added.

Comparative Example 6 A copper clad laminate was obtained in the same manner as in Example 10 except that pyrogallol was not added.

The composite copper-clad laminates obtained in Examples 10 to 12 and Comparative Examples 5 and 6 were evaluated for tracking resistance and copper migration resistance. The results are shown in Table 4.

[0055]

[Table 4] Examples 10 to 12 in which a metal scavenger is blended are Comparative Example 5,
6, the tracking resistance was good, and the copper migration resistance was good as compared with Comparative Example 6.

[0056]

As is apparent from the above description, according to the present invention, a composite laminated board having excellent tracking resistance, an epoxy resin composition for printed wiring boards and a prepreg which are preferably used for the production thereof can be obtained.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number for FI FI technical display location // B32B 15/08 J (72) Inventor Han Myungde, 1500 Ogawa, Shimodate-shi, Ibaraki Hitachi Chemical Co., Ltd. Shimodate Research Institute Co., Ltd.

Claims (6)

[Claims] 1. A printing comprising (a) an epoxy resin, (b) a dicyandiamide or a polycondensate of bisphenol A and formaldehyde, (c) an inorganic filler and (d) a metal scavenger as essential components. Epoxy resin composition for wiring board. 2. An (a) epoxy resin, (b) dicyandiamide or a polycondensate of bisphenol A and formaldehyde, (e) a reducing agent, (c) an inorganic filler and (d) a metal scavenger are added as essential components. An epoxy resin composition for a printed wiring board, which is characterized in that: 3. The epoxy resin composition for a printed wiring board according to claim 2, wherein the reducing agent is a phenol-based reducing agent. 4. The (d) metal scavenger is one or more compounds selected from the group consisting of (f) triazine thiol compound, (g) thiazole compound, (h) oxine compound, and (i) triazine compound. The epoxy resin composition for printed wiring boards according to claim 1, 2 or 3. 5. A prepreg for a printed wiring board, which is obtained by impregnating a glass cloth or a glass nonwoven fabric with a varnish comprising the epoxy resin composition for a printed wiring board according to claim 1, 2, 3 or 4, and then drying the varnish. Production method. 6. A prepreg for a surface cloth is produced by impregnating a glass cloth with a varnish comprising the epoxy resin composition for a printed wiring board according to claim 1, 2, 3 or 4 and drying the prepreg. A method for producing a composite laminate, comprising laminating and molding prepregs on both sides of a core prepreg.