JP2595850B2 - Resin composition for laminate and laminate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated board and a resin composition for a laminated board suitable as an insulating substrate for a printed wiring board handling high frequencies.

[0002]

2. Description of the Related Art As an insulating substrate for a printed wiring board, a laminated board formed by laminating a predetermined number of prepregs obtained by impregnating and drying a glass cloth base material with an epoxy resin or polyimide and heating and pressing them is used. These laminates have a large dielectric constant of 4.9 to 5.1, and when used as an insulating substrate of a printed wiring board, the capacitance of the printed wiring board becomes large, which is unsuitable for those handling high frequencies. As an insulating substrate of a printed wiring board suitable for a high frequency region, one having a low dielectric constant and a low dielectric loss tangent is required. As such a product, a laminated board in which a glass cloth base material is impregnated with a thermoplastic resin having a low dielectric constant has been proposed, but the manufacturing process is extremely complicated, and the dimensional stability at high temperatures such as soldering processing is poor. Bad and expensive. It has also been proposed to use a polybutadiene-based resin, but since this resin is liquid at room temperature, it is difficult to make a dry prepreg, and the prepreg is not easy to handle. Further, the adhesiveness to the metal foil is poor and the heat resistance is low.

Further, a laminate having improved dielectric properties, heat resistance and moisture resistance by using a resin composition in which a phenol-added butadiene (co) polymer is mixed with an epoxy resin has been proposed (Japanese Patent Application Laid-Open No. Hei 1 (1994)). 163256). In a polymer material, when an atom having a high electron density such as an oxygen atom or a nitrogen atom is present in a molecule, dipole polarization or ionic polarization is formed in an electric field. If the molecular structure is depolarized, such as polyethylene, in order to lower the dielectric constant and dielectric loss, the dielectric properties will be good but the heat resistance will be poor. The technology disclosed in the above publication depolarizes the molecular structure of the polymer material and at the same time increases the molar capacity of the constituent atomic groups to increase the heat resistance. However, the phenol-added butadiene (co) polymer has a large molecular weight. In addition, when the prepreg is prepared by impregnating and drying the sheet-like base material, the surface of the prepreg foams, and voids are formed in the formed laminate.
The void is a fatal defect as an insulating substrate of the printed wiring board, and a laminated board including such a void cannot be used as an insulating substrate of the printed wiring board.

[0004]

The problem to be solved by the present invention is to maintain the dielectric properties, heat resistance and moisture resistance of the laminate and to prevent voids in the laminate due to foaming on the prepreg surface. And to obtain a resin composition for a laminate for that purpose.

[0005]

In order to solve the above-mentioned problems, a resin composition for a laminate according to the present invention comprises (a) an epoxy resin, and (b) a butadiene (1,2) having 40% or more of 1,2 bonds. A phenol-added butadiene (co) polymer obtained by adding a phenol to a (co) polymer, and (c) a phenol-added dicyclopentadiene are essential components. Preferably, the blending amount of the phenol-added butadiene (co) polymer is 90 parts by weight or less based on 100 parts by weight of the total of the phenol-added dicyclopentadiene resin and the phenol-added butadiene (co) polymer. The number average molecular weight of the phenol-added dicyclopentadiene resin is 1,000 or less. In addition, the laminate according to the present invention, in a laminate obtained by laminating a sheet-like substrate impregnated and dried with a thermosetting resin, and applying heat and pressure molding, the above-described resin composition for a laminate was used as the thermosetting resin. Things.

[0006]

The phenolic adduct of butadiene (co) polymer having 1,2 bonds of 40% or more as the component to be mixed with the epoxy resin alone was impregnated and dried on a sheet-like substrate because of its high softening temperature. Sometimes, the prepreg surface is in a foamed state. Therefore, by blending a phenol-added dicyclopentadiene having a low softening temperature,
A prepreg having a good appearance can be manufactured. When the butadiene (co) polymer used has less than 1% 1,2 bonds, the heat resistance of the resin composition is poor. By adjusting the blending amount of the phenol-added butadiene (co) polymer to 90 parts by weight or less based on 100 parts by weight of the total of the phenol-added dicyclopentadiene and the phenol-added butadiene (co) polymer, Foaming can be further suppressed, and foaming on the surface of the prepreg can be further suppressed by setting the number average molecular weight of the phenol-added dicyclopentadiene to 1,000 or less.

[0007]

The epoxy resins used in the present invention are bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, alicyclic epoxy resin, glycidyl. Ester type epoxy resin, glycidylamine type epoxy resin, isocyanurate type epoxy resin, polycondensation product of bisphenol A or bisphenol F and formaldehyde, glycidyl etherified product or halide thereof, hydrogenated product, etc., and is not particularly limited. . These epoxy resins may be used alone or in combination of two or more. When flame retardancy is required for a printed wiring board, addition of a halogenated epoxy resin is not a problem.

The phenol-added butadiene (co) polymer is a butadiene homopolymer or a butadiene copolymer obtained by copolymerizing butadiene with a vinyl monomer such as styrene or a diolefin such as isoprene, and phenols.
Protic acids such as sulfuric acid, perchloric acid, benzenesulfonic acid, paratoluenesulfonic acid, malic acid, aluminum chloride, boron trifluoride, boron trifluoride ether ether complex,
It is produced by reacting with a Lewis acid such as boron trifluoride / phenol complex as a catalyst. The amount of the catalyst used can be appropriately selected in the range of 0.01 to 10 parts by weight based on 100 parts by weight of the butadiene (co) polymer. The reaction temperature is
The temperature is not particularly limited, but is preferably from 40 ° C to 17 ° C.
0 ° C.

The phenol-added dicyclopentadiene represented by the chemical formula (1) is produced by reacting dicyclopentadiene and a phenol under the same catalyst as in the case of the phenol-added butadiene (co) polymer. You.

[0010]

Embedded image

The above phenol-added butadiene (co)
The phenols used to produce the polymer and the phenols-added dicyclopentadiene are monohydric phenols,
It is at least one selected from polyhydric phenols and their alkyl-substituted and bromine-substituted products.

In the resin composition according to the present invention, a phenol-added butadiene (co) polymer and a phenol-added dicyclopentadiene act as a curing agent for an epoxy resin. Known and commonly used curing accelerators such as benzylamine, tertiary amines, imidazoles, and various metal compounds can be used.
If necessary, various known and commonly used additives such as a filler and a coloring agent can be blended.

The laminate according to the present invention is manufactured by impregnating and drying a prepreg obtained by impregnating the above resin composition into a sheet-like substrate and then heating and pressing the prepreg. Glass fiber nonwoven fabric, polyamide fiber cloth, polyamide fiber nonwoven fabric, polyester fiber cloth, polyester fiber nonwoven fabric, and mixed nonwoven fabrics and mixed woven fabrics thereof. When molding the laminate, a metal foil can be integrally attached to the surface, but the metal foil is a copper foil, an aluminum foil, a nickel foil, or the like. They are not particularly limited. The metal foil can be coated with an adhesive beforehand on its bonding surface as required. Examples of the adhesive include phenolic, epoxy,
General-purpose metal foil adhesives such as butyral-based, polyester-based, polyurethane-based, and mixtures thereof can be used. The details will be described below.

Synthesis Example 1 100 g of polybutadiene B-1000 (1,2 bond 58%, number average molecular weight 1000, manufactured by Nippon Petrochemical), 250 g of phenol and 3.4 g of boron trifluoride / phenol complex were refluxed with a condenser and a stirrer. , And reacted at 80 ° C. for 3 hours. Then, 300 g of xylene, 8.6 g of calcium hydroxide and 0.1 g of water.
9 g was added, and the mixture was stirred at 90 ° C. for 20 minutes and filtered. Unreacted phenol and xylene are removed from the obtained filtrate under reduced pressure, and a phenol-added butadiene polymer (resin A) is obtained.
I got The number average molecular weight of Resin A was 1500.

Synthesis Example 2 A flask equipped with a thermometer, a reflux condenser, a stirrer and a dropping tube was charged with 100 g of phenol, and kept at 100 ° C., and 1.3 g of boron trifluoride / phenol complex was added. 42 g of pentadiene was added dropwise over 4 hours. After the dropwise addition, the mixture was kept at 100 ° C. for 1 hour, and unreacted components were removed at 150 ° C. and 4 mmHg to obtain phenol-added dicyclopentadiene (resin B). The number average molecular weight of Resin B was 660.

Synthesis Example 3 100 g of phenol was placed in a flask equipped with a thermometer, a reflux condenser, a stirrer, and a dropping tube, and 1.3 g of boron trifluoride-phenol complex was added at 100 ° C., followed by dicyclohexane. 85 g of pentadiene was added dropwise over 4 hours. After the dropwise addition, the mixture was kept at 100 ° C. for 3 hours, and unreacted components were removed at 150 ° C. and 4 mmHg to obtain phenol-added dicyclopentadiene (resin C). The number average molecular weight of the resin C is 1180
Met.

Examples 1 to 5, Conventional Example 1 Resins A, B, and A, B obtained in Synthesis Examples 1, 2, and 3 as various epoxy resins and a curing agent in the mixing ratio (parts by weight) shown in Table 1.
C was used and 2-ethyl-4-methylimidazole was added as a curing accelerator to obtain a resin composition for a laminate.
The resin composition was impregnated and dried in a glass fiber woven fabric to obtain a prepreg having a resin amount of 42% by weight. Four prepregs were stacked, and an electrolytic copper foil having a thickness of 18 μm was placed above and below the prepregs.
It was heated and pressed at 70 ° C. for 1 hour to obtain a copper-clad laminate.
The properties of this laminate are also shown in Table 1.

In the following table, epoxy resins 1 to 3
Is as follows. Epoxy resin 1: Epoxy equivalent 490, Ep-100
1, Yuka Shell epoxy resin 2: epoxy equivalent 390, ESB-40
0, Toto Kasei epoxy resin 3: Epoxy equivalent 210, YDCN-70
4, manufactured by Toto Kasei In the table below, the measuring methods and evaluation criteria for each property are as follows. The evaluation of the prepreg surface is "○",
The laminate of “△” had no inclusion of voids. A large number of voids were observed in the laminate of “x”. Tg (glass transition) temperature: using a thermo-mechanical analyzer Moisture absorption: weight increase after 48 hours in 40 ° C.-90% RH Dielectric constant, dielectric loss tangent: conform to JIS-C-6481 Prepreg surface: ○ No foaming, △ Slightly foamed, × foamed or sticky

[0019]

[Table 1]

Conventional Example 2 At the compounding ratio (parts by weight) shown in Table 2, various epoxy resins and dicyandiamide as a curing agent were used, and 2-ethyl-4-methylimidazole was added as a curing accelerator.
A resin composition for a laminate was obtained. Using this resin composition, a copper-clad laminate was formed in the same manner as in Example 1. Table 2 also shows the characteristics of the laminate.

Conventional Example 3 Epoxidized polybutadiene (epoxy equivalent: 205, BF-1000, manufactured by Nippon Soda) and a bifunctional phenol as a curing agent were used at a compounding ratio (parts by weight) shown in Table 2, and 2 as a curing accelerator. -Ethyl-4-methylimidazole was added to obtain a resin composition for a laminate. Using this resin composition, a copper-clad laminate was formed in the same manner as in Example 1.
Table 2 also shows the characteristics of the laminate.

[0022]

[Table 2]

[0023]

As is clear from Table 1, by using the resin composition according to the present invention, dielectric properties, heat resistance,
Since moisture resistance is maintained and foaming on the surface of the prepreg is suppressed, a laminate having no voids can be provided. The blending amount of the phenol-added butadiene (co) polymer is set to 90 parts by weight or less based on 100 parts by weight of the total of the phenol-added dicyclopentadiene and the phenol-added butadiene (co) polymer, or By controlling the number average molecular weight of the cyclopentadiene resin to 1,000 or less, the suppression of voids becomes even more remarkable.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location C08L 63/00 NJQ C08L 63/00 NJQ H05K 1/03 610 7511-4E H05K 1/03 610L

Claims (4)

(57) [Claims] 1. An epoxy resin, (b) a phenol-added butadiene (co) polymer obtained by adding phenols to a butadiene (co) polymer having 40% or more 1,2 bonds, and (c) A resin composition for a laminate comprising a phenol-added dicyclopentadiene as an essential component. 2. The resin composition for a laminate according to claim 1, wherein the component (b) is 90 parts by weight or less based on 100 parts by weight of the total of the components (b) and (c). 3. The resin composition for a laminate according to claim 1, wherein the component (c) has a number average molecular weight of 1,000 or less. 4. The thermosetting resin composition according to claim 1, wherein the thermosetting resin is a laminate obtained by laminating sheet-like substrates impregnated with a thermosetting resin and forming the laminate by heating and pressing. A laminate that is an object.