JPH06248074A - Low-dielectric thermosetting resin composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition containing a cyanate ester compound, etc., a phenol compound and a brominated epoxy resin having a specified bromine content, exhibiting a low dielectric constant and a low dielectric dissipation factor, excellent in adhesion, flame retardancy and chemical resistance and useful for a printed-wiring board, etc. CONSTITUTION:This low-dielectric thermosetting resin composition exhibiting a low dielectric constant and a low dielectric dissipation factor, excellent in adhesion to a metal, flame retardancy, heat resistance and chemical resistance and most suitable for a printed-wiring board is obtained by blended (A) 100 pts.wt. cyanate ester compound [e.g. 2,2-bis(4-cyanatephenyl)propane] represented by formula I [R1 is a >= divalent aromatic residue, cyanate ester group is directly bonded to R1 and the aromatic ring; (n) is an integer of >=2] and/or its prepolymer with (B) 50 to 200 pts.wt. phenol compound expressed by formula II [(q) and (r) are each 0 or an integer of >=1; (s) is a natural number; X is H or an alkyl] and (C) 50 to 200 pts.wt. brominated epoxy resin having >=30wt.% bromine content.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermosetting resin composition having a low dielectric constant, a low dielectric loss tangent, a high heat resistance and a flame retardant property, which is excellent in adhesiveness to a metal, and is laminated. Board,
It is preferably used for metal foil-clad laminates and the like.

[0002]

2. Description of the Related Art In recent years, there has been a demand for a resin for a laminated board which has excellent heat resistance, low dielectric constant and low dielectric loss tangent for printed wiring used in a high frequency region. On the other hand, a thermoplastic resin such as a fluororesin or a polyphenylene ether resin having a small dielectric constant has been proposed, but it has problems such as poor workability and adhesiveness and lack of reliability. Therefore, an epoxy-modified polyphenylene ether resin or a polyphenylene ether-modified epoxy resin has been proposed for the purpose of improving workability and adhesiveness. However, the epoxy resin has a high dielectric constant, and satisfactory characteristics have not been obtained. A curable resin composition prepared by blending a polyphenylene ether resin and a polyfunctional cyanate ester resin, and further another resin, adding a radical polymerization initiator and preliminarily reacting the mixture (JP-A-57-185350). However, the decrease in the dielectric constant was insufficient.

Polybutadiene containing thermosetting 1,2-polybutadiene as a main component has a low dielectric constant, but has poor adhesiveness and insufficient heat resistance. Polyphenylene ether
There is known a composition containing 5 to 20 parts by weight of 1,2-polybutadiene, 5 to 10 parts by weight of a crosslinkable monomer and 100 parts by weight of a radical crosslinking agent (see JP-A-61-83224). When 1,2-polybutadiene having a molecular weight of several thousand is used, stickiness remains when the solvent is removed from the composition, and the prepreg obtained by coating and impregnating a glass substrate etc. cannot maintain a tack-free state. So there was a problem in practice. On the other hand, there is a method of using a high molecular weight 1,2-polybutadiene to eliminate stickiness, but this method has a practical problem because the solubility in a solvent is lowered, the solution becomes highly viscous and the fluidity is lowered. It was

[0004]

DISCLOSURE OF THE INVENTION The present invention has been earnestly studied to obtain a thermosetting resin having a low dielectric constant, low dielectric loss tangent, high heat resistance, high adhesiveness and excellent flame retardancy. It was made.

[0005]

The present invention comprises (a) 100 parts by weight of a cyanate ester compound represented by the general formula (1) and / or a prepolymer thereof, and (b) a phenol compound represented by the general formula (2). A low dielectric constant thermosetting resin composition comprising 50 to 200 parts by weight and (c) 50 to 200 parts by weight of a brominated epoxy resin having a bromine content of 30 wt% or more.

[Chemical 1]

[0006]

The cyanate ester compound represented by the general formula (1) and / or the prepolymer thereof used in the present invention means an organic compound having two or more cyanate ester groups in the molecule. In the present invention, the polyfunctional cyanate ester itself or a prepolymer derived therefrom can be used. These compounds are, if necessary, zinc naphthenate, cobalt naphthenate, copper naphthenate, lead naphthenate, zinc octylate,
By using a catalyst such as tin octylate, lead acetylacetonate, and dibutyltin maleate, the cyanate ester group can be trimerized and the reaction can be adjusted appropriately to form a prepolymer. The cyanate ester group can form a sym-triazine ring in the molecule by trimerization and can be finally heat-cured. The cured product of the cyanate ester compound and / or its prepolymer alone has excellent heat resistance and gives a relatively low dielectric constant and dielectric properties, but it is still insufficient as a resin for high-frequency substrates. It is excellent in heat resistance, flame retardancy, adhesiveness, and chemical resistance for the first time when it is blended with the phenol compound or brominated epoxy resin of (2) and cured by heating.
Further, it is possible to provide a resin having excellent dielectric properties required for a resin for a high frequency substrate.

The cyanate ester compound used in the present invention is not particularly limited as long as it is represented by the general formula (1), but specific examples are 1,3-dicyanatebenzene, 1, 4-dicyanate benzene, 1,3,5-
Tricyanate benzene, 1,8- or 2,6- or 2,7-dicyanate naphthalene, 4,4'-dicyanate biphenyl, bis (4-cyanatophenyl) methane, 2,2-bis (4 -Cyanatophenyl) propane, bis (3,5-dimethyl-4-cyanatophenyl) methane, 2,2-bis (3,5-dimethyl-4-cyanatophenyl) propane, bis (4-cyanatophenyl) ) Sulfone, tris (4-cyanatophenyl) phosphite, 1,1-bis (4-cyanatophenyl) ethane, 2,2-bis (4-cyanatophenyl) hexafluoropropane and the like.

The phenol compound used in the present invention is represented by the general formula (2), but since it has a phenolic hydroxyl group in the molecule, it functions as a curing agent for the epoxy resin. Further, since the molecular skeleton has an aliphatic cyclized structure, it also has a function of lowering the values of the dielectric constant and the dielectric loss tangent, which is preferable. Specific examples of the phenol compound used in the present invention include special phenol resins PP-700-300, PP-700-180 and PP-1000-18 manufactured by Nippon Oil Co., Ltd.
However, the number is not particularly limited to these. It is also possible to use a reaction accelerator such as imidazole to accelerate the reaction with the epoxy group.

The brominated epoxy resin used in the present invention has the high adhesiveness of the epoxy resin and the effect of imparting flame retardancy due to the bromine atom, and its bromine content is preferably 30 wt% or more. If it is less than 30 wt%, the effect of imparting flame retardancy becomes poor, which is not preferable.

The low dielectric constant thermosetting resin composition of the present invention is
The cyanate ester compound of component (a) and / or its prepolymer, the phenol compound of component (b), and the brominated epoxy resin of component (c) are blended. a) 50 to 200 parts by weight of component (b) and 50 to 200 parts by weight of component (c) with respect to 100 parts by weight.
It is preferably part by weight. Component (b) is component (a)
If it is less than 50 parts by weight with respect to 100 parts by weight, it is not preferable because it has little effect on lowering dielectric constant and low dielectric loss tangent, and if it exceeds 200 parts by weight, a large amount of unreacted phenolic hydroxyl group remains in the cured resin. On the contrary, it is not preferable because the dielectric characteristics are impaired. When the amount of the component (c) is less than 50 parts by weight relative to 100 parts by weight of the component (a), the flame retarding effect and the adhesiveness improving effect are poor, which is not preferable, and when it exceeds 200 parts by weight,
This is not preferable because it causes deterioration of the dielectric properties.

The resin composition of the present invention is used in various forms, but a solvent is often used when coating and impregnating a substrate. It is necessary that the solvent used has good solubility in part or all of the composition, but a poor solvent can be used as long as it does not adversely affect the composition. Examples of the solvent used include acetone, methyl ethyl ketone, methyl isobutyl ketone, ketone solvents such as cyclohexanone, toluene, xylene, aromatic hydrocarbon solvents such as mesitylene, methyl cellosolve, ethyl cellosolve, butyl cellosolve, isobutyl cellosolve, diethylene glycol. Various types of monomethyl ether, triethylene glycol monomethyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monopropyl ether, dipropylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, etc. Glycol ether solvent, methylse Solvent acetate, ethyl cellosolve acetate, butyl cellosolve acetate, ester solvent such as ethyl acetate, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dialkyl glycol ether solvent such as diethylene glycol dibutyl ether, N, N-dimethylacetamide, N, N -There are amide solvents such as dimethylformamide and N-methyl-2-pyrrolidone, and alcohol solvents such as methanol and ethanol, and several of them can be used in combination.

The varnish obtained by dissolving the resin composition of the present invention in the above solvent is a glass woven cloth, a glass nonwoven cloth or paper,
Alternatively, a prepreg for a printed wiring board can be obtained by coating and impregnating a base material such as a cloth containing a component other than glass and drying the base material in a drying oven at a temperature of 80 to 200 ° C. The prepreg is used for producing a printed wiring board by heating and pressing, but the resin composition of the present invention has a low dielectric constant, a low dielectric loss tangent, excellent workability, high adhesiveness to a metal, and high heat resistance. It is a flame-retardant thermosetting resin having excellent chemical resistance, and is suitably used for laminated plates, metal-clad laminated plates and the like.

[0013]

EXAMPLES The present invention will now be described in more detail by way of examples.

(Example 1) 100 parts by weight of 2,2-bis (4-cyanatophenyl) propane, 120 parts by weight of special phenol resin PP-700-180 manufactured by Nippon Oil Co., Ltd., manufactured by Sumitomo Chemical Co., Ltd. 100 parts by weight of brominated epoxy resin ESB-400, toluene /
A mixed solvent of methyl ethyl ketone 1: 1 was added to adjust the varnish solution to a non-volatile concentration of 50%. When 10% nonylphenol solution of cobalt naphthenate was gradually added to this solution and the gel time of the varnish on the heating plate at 170 ° C was adjusted to 4 minutes ± 15 seconds.
When 5 parts by weight was added, it became 3 minutes and 58 seconds.

Then, using this varnish, 100 parts of glass cloth (0.18 mm in thickness, E glass manufactured by Nitto Boseki Co., Ltd.) was impregnated with 100 parts of the varnish with a solid content, and dried in a drying oven at 150 ° C. for 4 minutes. A prepreg having a resin content of 50 wt% was prepared by drying. The obtained prepreg was tack-free and had excellent workability. 8 pieces of the above-mentioned dried prepregs are piled up and the thickness is 35
Overlaid with electrolytic copper foil of μm, pressure 40kgf / cm ² , temperature 175 ℃
It was heated and pressed for 90 minutes to obtain a laminated plate having a thickness of 1.6 mm.
After removing the surface copper foil of this laminate by etching, 121 ° C
Was treated under a pressure cooker condition of 2.0 atm for 20 hours, and the weight increase was measured. The same test piece was immersed in methylene chloride at room temperature for 10 minutes, and the appearance was checked to check the solvent resistance. The results are shown in Table 2.

The measurement of the dielectric constant and the dielectric loss tangent is JIS C
It carried out according to 6481 and measured and calculated | required the electrostatic capacitance of frequency 1MHz. JIS C for solder heat resistance and peel strength
It was measured according to 6481, and the solder heat resistance was examined at 260 ° C. for 300 seconds to see if there was any abnormality in the appearance. The flame retardancy was evaluated by the vertical method according to UL-94 standard. The glass transition temperature was determined from the peak temperature of tan δ by the viscoelastic method. The results are shown together in Table 2.

(Examples 2 to 6 and Comparative Examples 1 to 5) Laminated plates were produced in the same manner as in Example 1 except for the compounding recipe shown in Table 1, and the results are shown in Table 2. .

[0018]

[Table 1]

[0019]

[Table 2]

[0020]

As is clear from the results of Tables 1 and 2, the resin composition of the present invention has a low dielectric constant, a low dielectric loss tangent, adhesion to metal, flame retardancy, heat resistance and chemical resistance. It is also an excellent thermosetting resin composition. Therefore, it is an optimal resin for printed wiring boards that require low dielectric constant and low dielectric loss tangent, and copper-clad laminates can be manufactured in the same process as conventional laminate resin, which is an industrial advantage. Is large.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Sumiya Miyake 1-2-2 Uchisaiwaicho, Chiyoda-ku, Tokyo Sumitomo Bakelite Co., Ltd.

Claims (1)

[Claims] 1. (a) 100 parts by weight of a cyanate ester compound represented by the general formula (1) and / or a prepolymer thereof, and (b) a phenol compound represented by the general formula (2) 50.
˜200 parts by weight, and (c) a low dielectric constant thermosetting resin composition comprising 50 to 200 parts by weight of a brominated epoxy resin having a bromine content of 30 wt% or more. [Chemical 1]