JPH07304930A - Phenolic resin composition and phenolic resin laminated sheet - Google Patents

Abstract

PURPOSE:To provide a phenolic resin laminated sheet, using paper as a substrate, having high heat resistance and tracking resistance and, at the same time, high stampability at room temp. and a phenolic resin compsn. for constituting the phenolic resin laminate sheet. CONSTITUTION:An unsatd. polyester resin, particularly an unsatd. polyester resin wherein the glycol component is a glycerol having the beta-hydroxyl group bonded to a higher fatty acid having 6 to 30 carbon atoms through an ester bond and the dibasic acid bonded to the alpha- and gamma-hydroxyl groups of the glycerol is an unsatd. dibasic acid is compounded with a flexibilizer-modified phenolic resin. The phenolic resin is impregnated into a paper substrate, and the impregnated paper substrate is dried to prepare a prepreg, which is then heated under pressure to prepare a laminated sheet.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phenol resin laminate used as an insulating substrate of a printed wiring board and a phenol resin composition which is a constituent material of the phenol resin laminate.

[0002]

2. Description of the Related Art Since a paper-based phenolic resin laminate has good workability, punching is often used. Phenolic resin synthesized only with phenols and formaldehyde is hard and has no plasticity, and the punching workability required for the current laminated board cannot be obtained. For that purpose, a paper substrate having a low elastic modulus is used. In addition, the phenol resin itself is given flexibility. As a means for imparting flexibility to a phenol resin, a method of modifying the phenol resin with a drying oil is widely adopted.

[0003]

Recently, the performance of electronic equipment has increased, and printed wiring boards have come to be used under severe conditions. Therefore, further improvement in heat resistance and tracking resistance is required. There is. Also, in punching, it is required that the holes be punched at a narrow interval of 1.78 mm and at room temperature. The present invention provides a paper-based phenol resin laminate having good heat resistance and tracking resistance and good punching property at room temperature, and a phenol resin composition which is a constituent material of the phenol resin laminate. It is intended.

[0004]

Means for Solving the Problems The present inventors have variously studied means for improving flexibility without impairing the heat resistance of the phenolic resin, and have confirmed that the aliphatic unsaturated polyester resin,
In particular, an aliphatic unsaturation in which a glycerin in which a β-hydroxyl group and a higher fatty acid having 6 to 30 carbon atoms are ester-bonded is used as a glycol component, and a dibasic acid bonded to the α- and γ-hydroxyl groups of the glycerin is a saturated or unsaturated fatty acid. It has been found that the above problem can be solved by blending a polyester resin.

That is, in the present invention, an unsaturated polyester resin, in particular, glycerin in which a β hydroxyl group and a higher fatty acid having 6 to 30 carbon atoms are ester-bonded to a flexibilizer-modified phenolic resin is used as a glycol component, and α of the glycerin is used. And a dibasic acid that binds to the γ-hydroxyl group is a phenol resin composition prepared by blending an unsaturated polyester resin which is an unsaturated fatty acid.

Examples of higher fatty acids having 6 to 30 carbon atoms which form an ester bond with β-hydroxyl group of glycerin include caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid,
Examples thereof include stearic acid, oleic acid, linoleic acid, and linolenic acid. When the carbon number is less than 6, the intended purpose of the present invention cannot be achieved. Further, higher fatty acids having more than 30 carbon atoms are difficult to obtain and are not practical.

As the dibasic acid that binds to the α and γ hydroxyl groups of glycerin, the dibasic acid usually used as the acid component of unsaturated polyester resins can be used. Examples of such dibasic acid include fumaric acid, maleic acid, maleic anhydride, and itaconic acid. Saturated acids such as malonic acid, succinic acid, phthalic acid, isophthalic acid, terephthalic acid, glutaric acid, and adipic acid may be used together if necessary.

Glycerin in which β-hydroxyl group and higher fatty acid having 6 to 30 carbon atoms are ester-bonded as a glycol component,
The unsaturated polyester resin in which the dibasic acid bonded to the α and γ hydroxyl groups of glycerin is an unsaturated fatty acid is reacted with glycerin and a higher fatty acid having 6 to 30 carbon atoms,
It is then obtained by reacting with an unsaturated dibasic acid.

Glycerin in which β-hydroxyl group and higher fatty acid having 6 to 30 carbon atoms are ester-bonded as a glycol component,
The dibasic acid that binds to the α and γ hydroxyl groups of glycerin is an unsaturated polyester resin that is an unsaturated fatty acid, and a paper base is impregnated with a varnish mixed with a drying oil-modified phenol resin synthesized by a known method and dried. To prepare a prepreg, stack the required number of sheets, heat and pressurize to form a laminated plate. The copper-clad laminate is obtained by simultaneously stacking a copper foil (usually using a copper foil with an adhesive) and a prepreg and heating and pressing.

As the phenol resin, a resol type phenol resin is used, and this resin is obtained by reacting phenols and formaldehyde in the presence of an alkali catalyst. As the phenols, phenol, meta-cresol, para-cresol, ortho-cresol, para-tert-butylphenol, para-isopropylphenol, para-isopropenylphenol oligomer nonylphenol, bisphenol A and the like are used.

Drying oil is a modifier for imparting flexibility to the phenol resin, and it has been proposed to use tung oil, dehydrated castor oil, linseed oil, deer oil, etc., but it has been put to practical use. The modifier is tung oil.

The blending amount of the polyester resin is 2 to 20 parts by weight based on 100 parts by weight of the flexible phenol resin solid content. If it is less than 2 parts by weight, no effect is obtained, and if it exceeds 20 parts by weight, the heat resistance becomes low.

A varnish obtained by dissolving a flexible phenol resin and a polyester resin in a solvent is impregnated into a paper base material and dried to obtain a prepreg. The solvent used is toluene, methanol, methyl ethyl ketone, acetone, dimethylformamide, styrene or the like.

It is known that punching workability and tracking resistance are mainly related to the surface of the laminated plate. Therefore, when a plurality of prepregs are used, the prepreg in which the surface layer is impregnated with the phenol resin composition of the present invention may be used, and the center layer may be used in which the drying oil-modified phenol resin is impregnated.

[0015]

The function of the present invention is not clear. Β of glycerin
It is considered that the fatty acid bonded to the hydroxyl group is appropriately entangled with the cured product of the phenol resin, thereby giving flexibility and improving heat resistance.

[0016]

【Example】

Example 1 100 parts by weight of ammonia resol phenol resin having a tung oil modification rate of 35%, glycerin in which β-hydroxyl group and stearic acid are ester-bonded as a glycol component, and the dibasic acid bonded to α- and γ-hydroxyl groups of glycerin is maleic acid. 10 parts by weight of a certain unsaturated polyester resin was dissolved in methanol to obtain a varnish. Kraft paper to which 12% by weight of water-soluble phenolic resin had been attached was impregnated with the varnish and dried to obtain a prepreg. Eight pieces of this prepreg were overlaid with a copper foil having a thickness of 35 μm and having an adhesive, and heated and pressed to obtain a single-sided copper-clad laminate having a thickness of 1.6 mm.

Example 2 A varnish was prepared by dissolving an ammonia-resole phenolic resin having a tung oil modification rate of 35% in methanol to form a varnish. The varnish was impregnated and dried on a kraft paper to which 12% by weight of a water-soluble phenolic resin had been attached in advance. And Seven pieces of this prepreg and a copper foil having a thickness of 35 μm and having an adhesive are stacked with one piece of the prepreg of Example 1 interposed therebetween, and heated and pressed to obtain a single-sided copper-clad laminate having a thickness of 1.6 mm. It was

Comparative Example Eight prepregs obtained in Example 2 and copper foil with a thickness of 35 μm and having an adhesive were stacked and heated and pressed to a thickness of 1.6 m.
A single-sided copper clad laminate of m was obtained. The obtained single-sided copper-clad laminate was examined for punching workability, tracking resistance and solder heat resistance. The results are shown in Table 1.

[0019]

[Table 1]

The punching workability is such that the hole pitch is 1.78 m.
The hole of m was punched at a temperature of 20 ° C. using an 80-ton press, and the presence or absence of peeling and the white of the eye was examined. Tracking resistance is measured by contacting electrodes at 4 mm intervals to a test piece from which copper foil has been removed by etching the entire surface, dropping a 0.1% aqueous solution of ammonium chloride between the electrodes, and dropping until the test surface is broken by tracking. Then, the voltage was changed, a relationship curve between the voltage and the number of drops was created, and the voltage corresponding to 50 drops was found. The solder heat resistance is obtained by floating the test piece in a solder bath at 260 ° C. and examining the time until blistering or peeling occurs.

[0021]

INDUSTRIAL APPLICABILITY According to the present invention, an unsaturated polyester resin, in particular, glycerin in which a β-hydroxyl group and a higher fatty acid having 6 to 30 carbon atoms are ester-bonded to a flexibilizer-modified phenolic resin is used as a glycol component. Α and γ of
The dibasic acid that binds to the hydroxyl group uses a phenol resin composition that is a mixture of unsaturated polyester resin, which is an unsaturated dibasic acid, as the matrix, so it has better tracking resistance and punching than the tung oil-modified phenol resin laminate. It is possible to obtain a paper-based phenol resin laminate having excellent heat resistance and solder heat resistance.

Front page continuation (72) Inventor Masafumi Yano 1500 Ogawa, Shimodate City, Ibaraki Prefecture Hitachi Chemical Co., Ltd. Shimodate Factory

Claims (3)

[Claims] 1. A phenol resin composition obtained by blending a flexible agent-modified phenol resin with an unsaturated polyester resin. 2. The unsaturated polyester resin comprises glycerin, in which β-hydroxyl group and higher fatty acid having 6 to 30 carbon atoms are ester-bonded, as a glycol component, and dibasic acid bonded to α- and γ-hydroxyl groups of glycerin is unsaturated. The phenol resin composition according to claim 1, which is a polyester resin characterized by being a fatty acid. 3. A phenol resin laminated plate obtained by laminating a prepreg obtained by impregnating and drying a paper substrate with the phenol resin composition according to claim 1 or 2.