JPH0517544A - Low dielectric constant resin composition - Google Patents

Abstract

PURPOSE:To provide the subject composition containing a fluorine-containing maleimide compound, an epoxidized polybutadiene, a specific halogen atom- containing bismaleimide compound, etc., having excellent flame resistance, excellent heat resistance and high toughness and suitable as a resin for the substrates of electric equipment printed circuit boards, etc. CONSTITUTION:The objective composition comprises (A) a fluorine-containing maleimide compound, (B) an epoxidized polybutadiene, (C) a halogen atom- containing bismaleimide compound of formula I[Z is a divalent group of formula II (X1-4 are Cl, Br; R1, R2 are H, methyl, ethyl, trifluoromethyl, trichloromethyl; (n) is an integer of 0-3)], and (D) an anionic polymerization initiator and/or an organic peroxide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition having a low dielectric constant having excellent electric characteristics, and particularly, a resin suitable for a substrate resin of a printed circuit board for electronic equipment and a heat resistant adhesive which require a low dielectric constant. It relates to a composition.

[0002]

2. Description of the Related Art Glass cloth epoxy resin laminates using epoxy resin as a binder have been widely used for printed circuit boards for electronic devices. However, with the miniaturization of electronic parts and high density wiring, Printed circuit boards are required to have improved heat resistance. Further, in recent years, in order to improve the data processing speed, it has become necessary to lower the dielectric constant of the resin for the substrate.

Polyimide resins such as bismaleimide have better heat resistance than epoxy resins, but their cured products have the drawback of being hard and brittle. In recent years, it has been attempted to apply a bismaleimide containing a fluorine atom to a resin for a substrate of a printed wiring board in order to achieve a low dielectric constant while utilizing the heat resistance of the bismaleimide compound. However, even when bismaleimide containing a fluorine atom is used, the point that it is hard and brittle has not been improved. Therefore, toughness is imparted to a cured product by copolymerizing an elastomer such as liquid polybutadiene with bismaleimide. However, when a hydrocarbon-based polymer such as polybutadiene is used as a resin for a printed circuit board, it is necessary to make it flame-retardant, and normally a bromine-containing compound that reacts with a double bond such as polybutadiene is used.

As a method for imparting flame retardancy to polybutadienes, for example, a method using an acrylic acid ester such as tribromophenol as disclosed in JP-B-53-21433 or JP-B-57-43162 is disclosed. Tetrabromobisphenol A as shown in
Method using acrylic acid ester such as
-167309 or a method using an acrylic acid ester of a tetrabromobisphenol A-ethylene oxide derivative or JP-A-61-23844.
There is a method of using an acrylic acid ester of a brominated polyhydroxystyrene oligomer as disclosed in Japanese Patent Laid-Open No.

Further, as a method for improving the flame retardancy and further improving the heat resistance of polybutadiene, JP-B-55-1682.
As disclosed in JP-A No. 62-167309 and JP-A No. 1-121356, there is a method of reacting a maleimide compound in addition to a bromine-containing compound of an acrylic acid ester.

[0006]

The conventional method using a bromine-containing compound of an acrylic acid ester is a resin obtained by the reaction of the compound with polybutadienes and imparting flame retardancy. There is a problem that the heat resistance of the composition is lowered. The present invention provides a low dielectric constant thermosetting resin composition having excellent flame retardancy and heat resistance.

[0007]

The present invention comprises: a) a maleimide compound containing a fluorine atom; b) an epoxidized polybutadiene; and b) a general formula [I].

[Chemical 3] (Where Z is

[Chemical 4] In the divalent group having the structure, at least one of X _{1 to} X ₄ represents chlorine or bromine, and they may be the same or different. R ₁ and R ₂ represent hydrogen, a methyl group, an ethyl group, a trifluoromethyl group or a trichloromethyl group, and may be the same as or different from each other. n shows the integer of 0-3. And a bismaleimide compound containing a halogen atom represented by the following), and d) an anionic polymerization initiator and / or an organic peroxide, which provides a flame-retardant thermosetting resin composition. .

In the resin composition of the present invention, a) the bismaleimide compound containing a fluorine atom is a maleimide compound substituted with a fluorine atom or a perfluoroalkyl group, and specifically, various fluorine-containing diamines such as bis (3 -Aminophenyl) perfluoroalkylene, 2,
2-bis (4-aminophenyl) hexafluoropropane, 2,2-bis (3-amino-4-methylphenyl)
Hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane,
Examples thereof include polymaleimide compounds obtained by bismaleimidization of 1,4-bis (4-aminophenoxy) tetrafluorobenzene, 4,4′-bis (4-aminophenoxy) octafluorobiphenyl and the like.

The b) epoxidized polybutadiene is excellent not only for obtaining excellent curability, but also for improving compatibility with a) bismaleimide compounds containing a fluorine atom and c) bismaleimide compounds containing a halogen atom. It has an epoxy group in order to obtain cured product characteristics. Specifically, epoxidized polybutadiene obtained by epoxidizing 1,2-bonding portion or 1,4-bonding portion of random polybutadiene, partially epoxidized polymer of 1,2-polybutadiene, and functional groups such as hydroxyl groups at their ends. Various polymers having an epoxy group as a basic skeleton of polybutadiene such as a derivative substituted with are used.

The bismaleimide compound containing a halogen atom of c) as the flame-retardant component is different from the conventional flame-retardant component.
Polymerization with epoxidized polybutadiene can improve heat resistance. The required amount of the bismaleimide compound varies depending on the amount of the epoxidized polybutadiene that is a combustible component. When the amount of the epoxidized polybutadiene is large, increase the amount of the bismaleimide compound containing a halogen atom. There is a need. The compounding amount of the compound a) or the compound c) as the heat resistant component is preferably in the range of 10 to 90% by weight based on all the resin components including itself. If it is less than 10% by weight, sufficient heat resistance cannot be obtained, and if it exceeds 90% by weight, the cured product becomes brittle but the cured product becomes brittle.

The bismaleimide compound containing a halogen atom represented by the general formula [I] is 2,2-bis [3,3].
5-dibromo-4- (4-maleimidophenoxy) phenyl] propane, 2,2-bis {3,5-dibromo-4
-[Β- (4-maleimidophenoxy) ethoxy] phenyl} propane is preferably used.

The compounds a), b) and c) according to the invention are
Both are dissolved in a solvent-free or a suitable solvent to prepare a composition.
Further, it is dissolved in a solvent-free or suitable solvent and, if necessary, is reacted with a catalyst to obtain a composition. An anionic polymerization catalyst and / or an organic peroxide, which is a curing catalyst of d), is added thereto and mixed to obtain a resin composition.

Examples of the anionic polymerization initiator used in the present invention include imidazoles such as 2-methylimidazole, 2-ethyl-4-methylimidazole and 2-phenylimidazole, amines such as benzyldimethyldiamine, triethylenediamine and DBU. , Dicyandiamide, triphenylphosphine, organometallic compounds, etc., and preferably 0.1 to 10 relative to the resin composition.
Wt% is added. Examples of the organic peroxide include benzoyl peroxide, dicumyl peroxide, methyl ethyl ketone peroxide, t-butyl perbenzoate and the like, preferably 0.1 to 0.1% with respect to the resin composition.
Add 10% by weight.

The impregnating varnish prepared by dissolving the flame-retardant thermosetting resin composition thus produced in an organic solvent is impregnated into glass fiber or the like and dried to form a prepreg sheet, and several sheets thereof are stacked. A laminated plate is manufactured by laminating at a predetermined temperature and pressure.

[0015]

The resin composition of the present invention comprises: a) a maleimide compound containing a fluorine atom; and b) epoxidized polybutadiene.
c) A resin composition composed of chlorine and / or an organic bronze oxide, which has a low dielectric constant by containing a fluorine atom, and has only a bismaleimide compound which is conventionally hard and brittle due to having a polybutadiene component. Compared with the resin cured product, it is possible to obtain a toughened resin cured product, and the flame retardant component is a bismaleimide compound with high heat resistance, so the flame retardancy of epoxidized polybutadiene is improved without impairing the heat resistance. It is possible.

[0016]

EXAMPLES The flame-retardant resin composition of the present invention will be specifically described in the following examples. Example 1 Polybd R-15EPI (epoxidized polybutadiene, trade name of Idemitsu Petrochemical Co., Ltd.) was dissolved in N, N'-dimethylformamide (hereinafter referred to as DMF) to prepare a 40 wt% polybutadiene solution. 2,2-bis [3,5
Dibromo-4- (4-maleimidophenoxy) phenyl] propane and 2,2-bis [4- (4-maleimidophenoxy) phenyl] hexafluoropropane at 60:
A 40 wt% bismaleimide solution was prepared by dissolving in 40 DMF.

The polybutadiene solution and the bismaleimide solution were mixed at a weight mixing ratio of 50:50, and the mixture was mixed at 160 ° C. for 2 hours.
The reaction was carried out by heating for an hour. Next, 0.4% by weight of 2-ethyl-4-methylimidazole and 0.2% by weight of dicumyl peroxide were added to obtain a varnish for impregnation.

A glass cloth (0.1 mm
(Thickness, manufactured by Nitto Boseki), and then dried at 170 ° C. for 3 minutes to remove the solvent and obtain a prepreg having a resin content of 55 wt%. Twelve of these prepregs and 35 .mu.m electrolytic copper foils were stacked on top and bottom, and laminated and molded under the conditions of a pressure of 40 kgf / cm @ 2, a temperature of 200.degree.

About this copper-clad laminate, dielectric constant, dielectric loss tangent, solder heat resistance, copper foil peeling strength (above JIS-C-
6481) and flame retardancy (UL-94-vertical method). The results are shown in Table 1. The obtained copper-clad laminate had no voids or scratches, and was excellent in dielectric constant, solder heat resistance, copper foil peeling strength and flame retardancy.

Example 2 In the preparation of a bismaleimide solution, 2,2-bis {3
5-dibromo-4- [β- (4-maleimidophenoxy) ethoxy] phenyl} propane and 2,2-bis [4
-(4-maleimidophenoxy) phenyl] hexafluoropropane was dissolved in DMF at a weight ratio of 60:40 to prepare a bismaleimide solution, and 70 parts by weight of this solution and 30 parts by weight of the same polybutadiene solution as in Example 1 were mixed. A copper clad laminate was prepared in the same manner as in Example 1 except for the above, and the characteristics thereof were measured. The results are shown in Table 1. The obtained copper-clad laminate had no voids or scratches, and was excellent in dielectric constant, solder heat resistance, copper foil peeling strength and flame retardancy.

Example 3 NISSO-PB BF-1000 (epoxidized 1,2
-Polybutadiene, trade name of Nippon Soda Co., Ltd.)
A varnish for impregnation was prepared in the same manner as in Example 1 except that the polybutadiene solution was prepared by dissolving in a varnish, and then a copper clad laminate was prepared in the same manner, and the characteristics thereof were measured. The results are shown in Table 1. The obtained copper-clad laminate had no voids or scratches, and was excellent in dielectric constant, solder heat resistance, copper foil peeling strength and flame retardancy.

Example 4 NISSO-PB BF-1000 (epoxidized 1,2
-Polybutadiene, trade name of Nippon Soda Co., Ltd.)
A varnish for impregnation was prepared in the same manner as in Example 2 except that the polybutadiene solution was prepared by dissolving in a varnish, then a copper clad laminate was prepared in the same manner, and the characteristics thereof were measured. The results are shown in Table 1. The obtained copper-clad laminate had no voids or scratches, and was excellent in dielectric constant, solder heat resistance, copper foil peeling strength and flame retardancy.

Comparative Example 1 In the preparation of the bismaleimide solution, 4,4'-diphenylmethane bismaleimide was dissolved alone in DMF to prepare a bismaleimide solution, which was reacted in the same manner as the polybutadiene solution of Example 1. Then, a commercially available flame retardant D-5001 (TBA methacrylate, trade name of Daiichi Kogyo Seiyaku Co., Ltd.) together with dicumyl peroxide was added so that the bromine content of the resin composition was 15% by weight. Was added to prepare a varnish for impregnation. Using this varnish, a copper clad laminate was prepared in the same manner as in Example 1 and its characteristics were measured.
The results are shown in Table 1. The obtained copper-clad laminate had neither voids nor scratches, but had a high dielectric constant and poor solder heat resistance.

Comparative Example 2 Polybd R-1 was used in the production of the polybutadiene solution.
5HT (end-hydroxy modified polybutadiene, 1,2-
A copper clad laminate was prepared in the same manner as in Example 1 except that 20% by weight of polybutadiene unit and trade name of Idemitsu Petrochemical Co., Ltd. were used, and the characteristics thereof were measured. The results are shown in Table 1. The obtained copper-clad laminate had a non-uniform appearance and phase separation was observed, and it was found that the compatibility of the polybutadiene component and the bismaleimide compound was insufficient.

[0025]

[Table 1]

[0026]

According to the present invention, it is possible to obtain a low dielectric constant resin composition having high toughness, excellent solder heat resistance and flame retardancy, and good adhesiveness, and its industrial value is extremely large. .

Claims (3)

[Claims] 1. A maleimide compound containing a fluorine atom, b) an epoxidized polybutadiene, and c) a compound represented by the general formula [I]: (In the formula, Z is In the divalent group having the structure, at least one of X _{1 to} X ₄ represents chlorine or bromine, and they may be the same or different. R ₁ and R ₂ represent hydrogen, a methyl group, an ethyl group, a trifluoromethyl group or a trichloromethyl group, and may be the same as or different from each other. n shows the integer of 0-3. A low-dielectric-constant resin composition comprising a bismaleimide compound containing a halogen atom represented by (4), and d) an anionic polymerization initiator and / or an organic peroxide. 2. The bismaleimide compound represented by the general formula [I] is 2,2-bis [3,5-dibromo-4- (4-
The flame-retardant thermosetting resin composition according to claim 1, which is maleimidophenoxy) phenyl] propane. 3. A bismaleimide compound represented by the general formula [I] is 2,2-bis {3,5-dibromo-4- [β-
The low dielectric constant resin composition according to claim 1, which is (4-maleimidophenoxy) ethoxy] phenyl} propane.