JPH0995596A - Highly tough phenolic resin molding material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a highly tough phenolic resin molding material excellent in moisture resistance, heat resistance and electrical properties by using a resin comprising a specific phenolic resin as the main component, a acrylonitrile/ butadiene rubber and a filler as 3 components. SOLUTION: This resin molding material comprises a resin comprising a resol phenolic resin as the main component, an acrylonitrile/butadiene rubber, and a filler as 3 components. A phenolic resin molding material wherein a resin component comprises 20-60 pts.wt. novolak phenolic resin and 100 pts.wt. dimethylene ether resol resin or methylol resol resin is preferable as the resol phenolic resin, and a phenolic resin molding material contg. 70-140 pts.wt. glass fiber is further preferable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-strength and high-toughness phenol resin molding material having excellent moisture resistance, heat resistance, and electrical characteristics, and more particularly to a phenol resin molding material suitable for small and thin electronic parts.

[0002]

2. Description of the Related Art Phenolic resins are excellent in heat resistance, strength, moldability, etc. among various thermosetting resins.
It is used for various purposes such as molding materials and laminates. Among them, a resol-type phenol resin molding material which is ammonia-free has been used for many electronic components in recent years. Such components are required to have characteristics such as moisture resistance, dimensional stability, heat resistance, and electrical insulation.
As the wall thickness becomes thinner, the strength and toughness of thinner molded products are being demanded. Generally, a phenol resin is mixed with glass fiber in order to obtain high strength, but it has a defect that it is three-dimensionally fragile in structure as compared with a thermoplastic resin. In order to improve this point, various fillers and elastomers have been investigated, but problems such as deterioration in moisture resistance and heat resistance, and inability to achieve both strength and flexibility can be satisfied Phenolic resin molding The material has not been obtained yet.

[0003]

DISCLOSURE OF THE INVENTION The present invention has excellent moisture resistance, heat resistance, and electrical characteristics and is suitable for small and thin electronic parts and the like, and has high strength. It is an object of the present invention to provide a high toughness phenolic resin molding material having improved properties.

[0004]

The present invention provides a high toughness phenolic resin molding characterized in that the resin main component is a resol type phenolic resin and contains three components of NBR and glass fiber and organic fiber as a filler. The material, wherein the resol type phenol resin is a dimethylene ether type resol resin or a methylol type resol resin, preferably containing a novolac type phenol resin, and the ratio of the novolac type phenol resin is the resol type phenol resin 1
The present invention relates to a phenol resin molding material which is 20 to 60 parts by weight with respect to 00 parts by weight, and a resin component 10
70 to 140 parts by weight of glass fiber is contained with respect to 0 part by weight, and the organic fiber is crushed cloth or the like.
5 parts by weight, NBR is a partially crosslinked or carboxy-modified type, and 10 to 20 parts by weight of NBR is contained, which relates to a phenol resin molding material.

The phenol resin molding material of the present invention uses a resol type phenol resin as a main component of the phenol resin, and is suitably used for electronic parts, especially for applications requiring corrosion resistance of copper wire. When a novolak-type phenol resin is used as a main component, hexamethylenetetramine is usually used as a curing agent, but it should be avoided since corrosive gas such as ammonia gas is generated during curing.

The resol type phenol resin is not particularly limited, such as a dimethylene ether type resol resin or a methylol type resol resin, but a dimethylene ether type resol resin is preferable in view of viscosity and heat stability at the time of heating and melting, and it has good curability. In consideration of the above balance, it is more preferable to use the dimethylene ether type resole resin and the methylol type resole resin in combination. Further, it is preferable that the amount of metal corrosion components such as ammonia generated is as small as possible, and it is preferable that the amount of ionic substances is small. The number average molecular weight of the resole type phenol resin is preferably from 500 to 1,000, and particularly preferably from 650 to 850. If it is less than 500, it is difficult to handle because it has a low melting point and is likely to be solidified at room temperature. If it exceeds 1000, the fluidity is lowered and the roll workability at the time of producing a molding material is deteriorated.

In the present invention, a novolac type phenol resin is preferably used together with the resol type phenol resin. By blending the novolac type phenolic resin, the strength and toughness of the molded product can be increased. The novolac type phenolic resin may be one having a number average molecular weight of 700 to 1000 used for ordinary molding materials, and 20 to 60 parts by weight, and further 30 to 30 parts by weight of the novolac type phenolic resin with respect to 100 parts by weight of the resol type phenolic resin. Fifty
Parts by weight are preferred. If it is less than 20 parts by weight, the strength and toughness of a molded product are not necessarily compatible with each other, and if it is added in an amount of 60 parts by weight or more, the curability of the molding material decreases, which is not desirable.

The glass fiber used as the filler may be generally commercially available, and the addition amount is preferably 70 to 140 parts by weight, more preferably 80 to 120 parts by weight, based on 100 parts by weight of the phenol resin component. Even if added in an amount of 140 parts by weight or more, no further improvement in strength is observed when the molding material is used as a molded product, and there is a problem that the fluidity of the molding material becomes worse. If it is less than 70 parts by weight, the desired strength cannot be obtained, which is not preferable.

The organic fiber used as the filler is a crushed cloth or the like, and the addition amount is preferably 5 to 25 parts by weight, more preferably 10 to 20 parts by weight with respect to 100 parts by weight of the phenol resin component. Even if added in an amount of 25 parts by weight or more, further improvement in toughness, that is, flexibility when a molding material is used as a molded product is not recognized, and there is a problem that fluidity deteriorates due to an increase in viscosity when the molding material melts. . On the other hand, if the amount is less than 5 parts by weight, there is almost no influence on the characteristics due to the addition, which is not preferable.

The NBR is preferably a partially crosslinked type or a carboxy-modified type, and the addition amount is preferably 5 to 25 parts by weight, more preferably 10 to 20 parts by weight based on 100 parts by weight of the phenol resin component. Even if added in an amount of 25 parts by weight or more, further improvement in toughness, that is, flexibility when a molding material is used as a molded product is not recognized, and there is a problem that fluidity deteriorates due to an increase in viscosity when the molding material melts. . On the other hand, if the amount is less than 5 parts by weight, there is almost no influence on the characteristics due to the addition, which is not preferable.

In forming a molding material, as in the case of a normal molding material, in addition to the above-mentioned phenol resin composition and filler, slaked lime which is a curing aid, a pigment, a release agent and the like are mixed and uniformly mixed. After that, a molding material can be obtained by kneading with a pressure kneader, biaxial extrusion, kneading with a heating roll or the like and crushing.

The phenolic resin molding material of the present invention is a high-strength, high-toughness phenolic resin molding material which is excellent in moisture resistance, heat resistance and electrical characteristics and is suitable for small and thin electronic parts and the like.
It is suitable for use in electronic components that require toughness such as crack prevention.

[0013]

EXAMPLE A phenolic resin molding material was produced according to the formulation shown in Table 1. Molded articles were obtained for each molding material, and their properties were measured and shown in the lower column of Table 1. For comparison of toughness, the bending strength of 0.5 mm thickness and the amount of deflection were measured and judged.

[0014]

[Table 1]

[Measuring Method] 1. Solder heat resistance: A test piece of 50φ × 3 mm thickness was transfer molded at 175 ° C. for 3 minutes. The obtained molded product was immersed in a solder bath at 430 ° C. for 3 seconds, and the rate of change in thickness was measured. 2. 0.5 mm thickness bending strength and deflection amount: JIS K 7
Based on No. 203, the span was set to 8 mm and the measurement was performed according to the thickness of the test piece.

[0016]

As is clear from the above Examples and Comparative Examples, the phenolic resin molding material of the present invention is excellent in moisture resistance, heat resistance and electrical properties. Furthermore, it is high strength,
Further, it is a high toughness phenolic resin molding material in which brittleness, which is a drawback of the thermosetting resin molding material, is improved, and is suitable for a small and thin molded product, particularly an electronic component, which requires these characteristics.

Claims (5)

[Claims] 1. A high toughness phenolic resin molding material, characterized in that the main component of the resin is a resol type phenolic resin, and contains acrylonitrile butadiene rubber and three components of glass fiber and organic fiber as a filler. 2. A novolac type phenolic resin as a resin component, wherein the resol type phenolic resin is a dimethylene ether type resole resin or a methylol type resole resin, and the proportion of the novolac type phenolic resin is 100 parts by weight of the resole type phenolic resin. 20 to 6
The phenol resin molding material according to claim 1, which is 0 part by weight. 3. The phenol resin molding material according to claim 1, which contains 70 to 140 parts by weight of glass fiber with respect to 100 parts by weight of the resin component. 4. The organic fiber is a crushed cloth, and the resin component 1
5 to 25 parts by weight based on 100 parts by weight,
The phenol resin molding material according to 2 or 3. 5. Acrylonitrile butadiene rubber (hereinafter referred to as NBR) is a partially crosslinked type or a carboxy modified type, and is 5 to 100 parts by weight of a resin component.
The phenol resin molding material according to claim 1, which contains 25 parts by weight.