JPH083423A - Phenolic resin composition and manufacture of phenolic resin laminate - Google Patents

Abstract

PURPOSE:To obtain a fire resistant phenolic resin composition excellent in dielectric properties, by adding a specific phosphate to a phenolic resin, and a phenolic resin laminate, by using it. CONSTITUTION:This phenolic resin composition comprises 100 pts.wt. phenolic resin and 20 to 60 pts.wt. phosphate represented by the formula (wherein R represents CH3 or CH2CH). This phenolic resin composition is formed into a varnish, the varnish is impregnated into a fibrous base to prepare a prepreg, and the prepreg is molded into a phenolic resin laminate.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a flame-retardant phenolic resin composition having excellent dielectric properties and a method for producing a phenolic resin laminate.

[0002]

2. Description of the Related Art It is known to blend a phenol resin with triphenyl phosphate in order to make an electrical phenol resin laminate flame-retardant. The compounding amount is 20 to 6 with respect to 100 parts (parts by weight, the same applies hereinafter) of the phenol resin.
It is 0. This is because if the content is 20 parts or less, the flame retardancy is insufficient, and if it is 60 parts or more, the punching workability is deteriorated.

[0003]

As the wiring density increases, a phenolic resin laminate having good dielectric properties is required. However, when triphenyl phosphate is mixed with the phenol resin, there is a drawback that the dielectric properties are deteriorated. The use of a flame retardant such as a bromine-based or inorganic compound is not preferable because the tracking resistance is deteriorated. The present invention uses a phosphoric acid ester as a flame retardant,
Moreover, the present invention provides a phenol resin composition for a phenol resin laminate having excellent dielectric properties and a method for producing a phenol resin laminate using the phenol resin composition.

[0004]

[Means for Solving the Problems] The inventors of the present invention have sought to find out why when a phenol resin is blended with triphenyl phosphate, the dielectric properties are deteriorated, and the triphenyl phosphate is decomposed in the process of producing a laminate. As a result, they found that phosphoric acid and phenol were produced, and reached the present invention. The present invention is based on 100 parts of phenolic resin and structural formula 2
20 to 60 parts of the phosphoric acid ester represented by (2) is blended.

[0005]

Embedded image

Structural formula 2 is added to 100 parts of phenol resin.
A phenol resin composition containing 20 to 60 parts of the phosphoric acid ester shown in (2) is used as a varnish, and a prepreg obtained by impregnating the varnish into a fiber base material is molded to obtain a laminated board.

The phenol resin is preferably a dry oil-modified phenol resin obtained by reacting a dry oil with phenols. As the drying oil, tung oil, linseed oil, dehydrated castor oil, deer oil, etc. are used. As the phenols, phenol, metacresol, paracresol, orthocresol, isopropylphenol, paratertiarybutylphenol, nonylphenol, bisphenol A and the like are used.

As the flame retardant, triphenyl phosphate, brominated phenol, brominated epoxy compound or brominated biphenyl ether compound may be used in combination. However, when they are used in combination, the amount is 1/2 or less of that of the phosphoric acid ester represented by Structural Formula 2 (2).

A phenol resin composition prepared by mixing 20 to 60 parts by weight of a phosphoric ester represented by the structural formula 2 (2) with 100 parts by weight of a phenol resin is prepared from toluene, alcohol, methyl ethyl ketone, acetone, styrene, etc. A varnish is formed using a solvent, a predetermined amount is impregnated and adhered to a base material such as paper, and the solvent is volatilized by heating to form a prepreg. Stack a predetermined number of these prepregs, stack copper foil on it,
Heat and pressurize at a required temperature and pressure to obtain a laminated plate.

[0010]

The phosphoric acid ester represented by the structural formula (2) does not hydrolyze because the substituent R at the 2,6 position acts as a steric hindrance.

[0011]

【Example】

Example 1 Tung oil and phenol were reacted under an acid catalyst, and then paraformaldehyde was reacted with an alkali catalyst to obtain a phenol resin having a modified tung oil content of 25% by weight, which was obtained by resolization. 100 parts of this phenol resin, tri 2,6-xylenyl phosphate (R: C of the structural formula 2 (2)
H ₃₎ was impregnated varnish 50 parts. A prepreg was obtained by impregnating and drying kraft paper which had been treated with a water-soluble phenol resin (resin content 12% by weight) in advance so that the amount of resin adhered was 50% by weight. Using eight prepregs, a copper foil with an adhesive was placed on the surface layer and heated and pressed to obtain a single-sided copper-clad laminate having a thickness of 1.6 mm.

Example 2 100 parts of the same phenolic resin as in Example 1, tri-2,6-
A single-sided copper-clad laminate having a thickness of 1.6 mm was obtained in the same manner as in Example 1 except that 25 parts of xylenyl phosphate and 25 parts of triphenyl phosphate were used as impregnating varnishes.

Comparative Example Using the same phenolic resin 100 parts and triphenyl phosphate 50 parts as in Example 1 as an impregnating varnish, a single-sided copper clad laminate having a thickness of 1.6 mm was obtained in the same manner as in Example.

The dielectric constant and the dielectric loss tangent of the obtained laminated plate were examined according to JIS C6481 over 20 to 1 MHz. The results are shown in Tables 1 and 2.

[0015]

[Table 1] ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Dielectric constant ─────────────── ──────────────── Frequency (Hz) Example 1 Example 2 Comparative example 20 6.0 6.2 6.8 100 100 5.2 5.6 6.1 1k 4 5.9 5.2 5.5 10k 4.7 5.0 5.0 5.2 100k 4.5 4.7 4.9 1M 4.0 4.0 4.4 4.6 ━━━━━━━━━━━━━ ━━━━━━━━━━━━━━━━━━

[0016]

[Table 2] ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Dielectric loss tangent ─────────────── Frequency (Hz) Example 1 Example 2 Comparative Example 20 0.1152 0.1321 0.2039 100 0.0592 0.0764 0.1099 1k 0.0436 0.0435 0.0551 10k 0.0390 0.0376 0.0466 100k 0.0359 0.0380 0.0403 1M 0.0327 0.0401 0.0423 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

From the results shown in Table 1 and Table 2, Example 1
It can be seen that the laminated plate of Example 2 has lower dielectric constant and dielectric loss tangent than the laminated plate of Comparative Example, and is excellent in dielectric properties.

[0018]

According to the present invention, a phenol resin varnish containing a phosphoric acid ester represented by the chemical formula 2 is impregnated and adhered to a substrate and molded to obtain a laminate having excellent dielectric properties. You can

Claims (2)

[Claims] 1. A phenol resin composition comprising 100 parts by weight of a phenol resin and 20 to 60 parts by weight of a phosphoric acid ester represented by the structural formula (1). Embedded image 2. A phenol resin composition comprising 100 parts by weight of a phenol resin and 20 to 60 parts by weight of a phosphoric ester represented by Structural Formula 1 (1) is used as a varnish, and the varnish is used as a fiber base material. A method for producing a phenol resin laminate, which comprises molding a prepreg obtained by impregnation.