JP3238222B2 - Low dielectric constant thermosetting resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high heat-resistant thermosetting resin composition having a low dielectric constant, a low dielectric loss tangent, and excellent adhesion to a metal. It is suitably used for plates and the like.

[0002]

2. Description of the Related Art In recent years, there has been a demand for a resin for a laminate having excellent heat resistance, a low dielectric constant, and a low dielectric loss tangent for a printed wiring used in a high frequency range. On the other hand, thermoplastic resins such as fluororesins and polyphenylene ether resins having a small dielectric constant have been proposed, but have 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 dielectric constant of the epoxy resin is high and satisfactory characteristics have not been obtained. A curable resin prepared by blending a polyphenylene ether resin and a polyfunctional cyanate ester resin (see JP-A-56-141349), and further mixing other resins, adding a radical polymerization initiator, and performing a pre-reaction. Although a composition (see JP-A-57-185350) is known, the decrease in the dielectric constant was insufficient.

Further, 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
A composition comprising 5 to 20 parts by weight of 1,2-polybutadiene, 5 to 10 parts by weight of a crosslinkable monomer and a radical crosslinking agent per 100 parts by weight (see JP-A-61-83224) is known. 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 on a glass substrate or the like cannot maintain a tack-free state. Therefore, there was a practical problem. On the other hand, in order to eliminate stickiness, there is a method using 1,2-polybutadiene having a high molecular weight.However, according to this method, the solubility in a solvent is reduced, the solution has a high viscosity, and the fluidity is reduced, which is a practical problem. Was.

[0004]

SUMMARY OF THE INVENTION The present invention has been made as a result of intensive studies to obtain a thermosetting resin having low dielectric constant, high heat resistance, high adhesiveness and excellent workability. .

[0005]

The present invention comprises (a) 100 parts by weight of polyphenylene ether, (b) 10 to 500 parts by weight of a phenol compound represented by the general formula (1), and (c) a compound represented by the general formula (2). 50 to 500 parts by weight of a cyanate ester compound and / or a prepolymer thereof, (d) a thermoplastic block copolymer and / or an epoxy group, a carboxylic acid group,
Thermoplastic block copolymer 5-2 in which at least one functional group selected from maleic anhydride groups has been introduced
It is a low dielectric constant thermosetting resin composition composed of 00 parts by weight.

Embedded image

[0006]

The polyphenylene ether used in the present invention is originally a thermoplastic polymer, but is a resin having excellent mechanical properties and electrical properties, especially dielectric properties, and good heat resistance. The polyphenylene ether of the present invention may be a homopolymer using only one type of phenol compound or a copolymer in which two or more types are combined, for example, poly (2,6-dimethyl-1, 4-phenylene) ether,
Poly (2-methyl-6-ethyl-1,4-phenylene) ether, poly (2,5-dimethyl-1,4-phenylene) ether, poly (2,6-
Examples thereof include a homopolymer represented by dibromo-1,4-phenylene) ether and a copolymer derived from 2,6-dimethylphenol and 2,3,6-trimethylphenol. Further, a phenol compound component containing a functional group such as an epoxy group or an unsaturated bond may be used as a part of the copolymer component.

The phenol compound used in the present invention is represented by the general formula (1), but has a phenolic hydroxyl group in the molecule and therefore functions as a co-catalyst for trimerizing cyanate esters. Further, since the molecular skeleton has an aliphatic cyclized structure, it has a function of lowering the dielectric constant and the dielectric loss tangent, which is preferable. Specific examples of the phenol compound used in the present invention include Nippon Oil
Special phenolic resins PP-700-300, PP-700-18
0, PP-1000-200, etc., but are not particularly limited thereto.

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

The cyanate ester compound used in the present invention is not particularly limited as long as it is represented by the general formula (2). Specific examples include 1,3-dicyanatobenzene and 1,3-dicyanatebenzene. 4-dicyanatobenzene, 1,3,5-
Tricyanatobenzene, 1,8- or 2,6- or 2,7-dicyanatonaphthalene, 4,4'-dicyanatobiphenyl, 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 thermoplastic block copolymer used in the present invention has the effect of improving the compatibility of different polymers and significantly improving the properties of the resulting cured product, especially the solder heat resistance and solvent resistance. Have. In the case where the different polymers are thermosetting resins, the compatibility of the polymers before crosslinking is improved, and the intermolecular distance can be reduced so that the interpenetrating network resin (IPN) can be more easily formed. Improve performance and chemical resistance. The same applies to the case of a combination of a thermoplastic polymer and a thermosetting polymer. Since the compatibility is increased, the thermoplastic polymer chains penetrate between the crosslinks of the thermosetting resin, and the semi-IPN structure is easily formed. In addition, various characteristics described above are improved.

[0011] Accordingly, the thermoplastic block copolymer used in the present invention is not particularly limited as long as it can exhibit the ability to improve the compatibility between different polymers. It is advantageous for the purpose of the present invention to have a component having a high molecular weight as a copolymer component. In addition, epoxy groups, carboxylic acid groups,
As long as a functional group incorporated into the crosslinked structure itself, such as a maleic anhydride group, is introduced, it is possible to prevent a decrease in heat resistance and chemical resistance caused by adding and blending a thermoplastic block copolymer. It is even more preferable. Needless to say, it can be used in combination with a thermoplastic block copolymer containing no functional group. Commercially available compatibilizers used in polymer alloys between thermoplastic resins can also be used for the purposes of the present invention. To give examples, `` Reseda '' series of comb-shaped graft polymers commercially available from Toa Gosei Chemical Industry Co., Ltd., `` Macromonomer '' series of reactive polymers, commercially available from NOF Corporation There are `` Modiper '' series, etc., especially those containing polystyrene units with high affinity for polyphenylene ether in the molecule,
For the purposes of the present invention are more preferred.

The low dielectric constant thermosetting resin composition of the present invention comprises:
(A) polyphenylene ether, (b) phenolic compound, (c) cyanate ester compound and / or prepolymer thereof, (d) thermoplastic block copolymer and / or
Alternatively, a thermoplastic block copolymer containing a functional group is blended, and the blending ratio thereof is (a)
For 100 parts by weight of the component, the component (b) is 10 to 500 parts by weight,
It is preferable that the component (c) is 50 to 500 parts by weight and the component (d) is 5 to 200 parts by weight. (B) component is (a) component 100
If the amount is less than 10 parts by weight, the effect of improving the function and dielectric properties of the cyanate ester as a trimerization co-catalyst is small. Is not preferred.
If the amount of the component (c) is less than 50 parts by weight, the heat-crosslinking component is decreased, and the heat resistance is unfavorably reduced. . If the component (d) is less than 5 parts by weight,
It is not preferable because the effect of compatibilizing polyphenylene ether and the thermosetting component is poor. If the amount exceeds 200 parts by weight, the heat resistance of the resin is undesirably reduced.

In addition, various additives can be added to the resin composition of the present invention in order to impart various properties within a range that does not impair the inherent properties of the composition. Halogenated compounds for imparting flame retardancy, phosphorus compounds, nitrogen compounds, flame retardants such as inorganic compounds, various coupling agents for improving adhesion to glass cloth and copper foil, for accelerating curing Examples include catalysts, accelerators, coloring agents such as pigments, and fillers.

Although the resin composition of the present invention is used in various forms, a solvent is often used when coating and impregnating a substrate. The solvent used must have 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, aromatic hydrocarbon solvents such as toluene, xylene and mesitylene, methyl cellosolve, ethyl cellosolve, butyl cellosolve, isobutyl cellosolve, diethylene glycol. Various types such as 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 Solvent acetate, ethyl cellosolve acetate, butyl cellosolve acetate, ester solvents such as ethyl acetate, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dialkyl glycol ether solvents 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 some of these can be used in combination.

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

[0016]

The present invention will be described below in more detail with reference to examples.

(Example 1) 200 parts by weight of poly (2,6-dimethyl-1,4-phenylene ether) (hereinafter abbreviated as PPE) having a number average molecular weight (hereinafter abbreviated as Mn) of 12000, Nippon Oil Co., Ltd.
400 parts by weight of special phenolic resin PP-700-180, 2,2-
Toluene was added to 400 parts by weight of bis (4-cyanatophenyl) propane and 200 parts by weight of Reseda GP-300 manufactured by Toa Gosei Chemical Industry Co., Ltd. to prepare a varnish solution so that the nonvolatile content concentration became 50%. Cobalt naphthenate was gradually added to the solution to adjust the gel time of the varnish on a hot plate at 170 ° C. to 4 minutes ± 15 seconds.

Thereafter, a glass cloth (0.18 mm in thickness, E-glass manufactured by Nitto Boseki Co., Ltd.) was impregnated with the varnish using the varnish so that the resin adhesion amount became 50 wt% of the total weight.
It was dried in a drying oven at 150 ° C. for 4 minutes to prepare a prepreg. The obtained prepreg was tack-free and excellent in workability. Lay 8 pieces of the dried prepreg, and put thickness on top and bottom
Overlaid 35μm electrolytic copper foil, pressure 40kgf / cm ² , temperature 175 ℃
For 90 minutes to obtain a laminate having a thickness of 1.6 mm. After etching and removing the surface copper foil of this laminate, 12
The mixture was treated under a pressure cooker condition at 1 ° C. and a pressure of 2.0 atm for 20 hours, and the weight increase was measured. The same test piece was immersed in methylene chloride for 10 minutes at room temperature, and the appearance was checked to determine the solvent resistance. Table 2 shows the results.

The measurement of the dielectric constant and the dielectric loss tangent are based on JIS C
The measurement was performed in accordance with 6481, and the capacitance at a frequency of 1 MHz was measured. JIS C for solder heat resistance and peel strength
The solder heat resistance was measured at 260 ° C. for 300 seconds to check for any abnormal appearance. 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. Table 2 shows the results together.

(Examples 2 to 6 and Comparative Examples 1 to 8) Laminates were manufactured in the same manner as in Example 1 except that the composition was as shown in Table 1 and the results are shown in Table 2. .

[0021]

[Table 1]

[0022]

[Table 2]

[0023]

As is clear from the results shown in Tables 1 and 2, the resin composition of the present invention has a low dielectric constant and a low dielectric loss tangent, and has excellent adhesiveness to metal, heat resistance and chemical resistance. It is a thermosetting resin composition. Therefore, it is the most suitable 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 resin for laminates, which is an industrial advantage. Is big.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-63-83152 (JP, A) JP-A-6-209709 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 1/00-101/16

Claims (2)

(57) [Claims] (1) 100 parts by weight of polyphenylene ether; (b) a phenolic compound represented by the general formula (1):
(C) a cyanate ester compound represented by the general formula (2) and / or a prepolymer thereof;
Parts by weight, (d) a thermoplastic block copolymer and / or a thermoplastic block copolymer into which at least one functional group selected from an epoxy group, a carboxylic acid group and a maleic anhydride group is introduced A low dielectric constant thermosetting resin composition comprising 5 to 200 parts by weight. Embedded image 2. The resin composition according to claim 1, wherein the thermoplastic block copolymer contains a styrene component.