JPH10120870A - Phenolic resin molding material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a phenolic resin material which can give a molding excellent in heat resistance and tracking resistance by mixing a resol phenolic resin as the main component with an inorganic filler which liberates its water of crystallization at 200 deg.C or above and an organic filler. SOLUTION: This material is obtained by mixing 20-40wt.% phenolic resin based on a resol phenolic resin with 45-60wt.% inorganic filler based on an inorganic filler which liberates its water of crystallization at 200 deg.C or above and 5-10wt.% organic filler. When a novolac phenolic resin is used in combination, it is used in an amount of at most 50wt.% based on the entire phenolic resin. The inorganic filler as the principal component is exemplified by aluminum hydroxide, magnesium hydroxide, talc or zeolite and is used in an amount of desirably at least 40wt.% based on the entire molding material. The organic filler is exemplified by a ground cloth or a pulp, which is desirable in respect of its ability to improve mechanical strengths. It is produced by mixing these components with other common additives such as a pigment and a curing agent and kneading the resulting mixture under heating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a phenolic resin molding material having excellent tracking resistance.

[0002]

2. Description of the Related Art Phenolic resin molding materials are excellent in heat resistance, dimensional stability, moldability and the like, and have been used for a long time in basic industrial fields such as automobiles, electricity and electronics. Especially,
Recently, demands for reliability of products have become strict, and electric performances such as arc resistance and tracking resistance have been required.

[0003] Usually, for parts requiring electrical performance, resins having excellent electrical properties such as unsaturated polyester, diallyl phthalate resin, melamine resin, and melamine / phenol resin are often used. There are also problems such as cost and cost, and it is desired to impart tracking resistance while maintaining excellent heat resistance, flame resistance and moldability of the phenol resin molding material.

[0004]

The present invention has been made as a result of various studies in order to solve such problems of the conventional phenolic resin molding material. It is an object of the present invention to provide a phenol resin molding material having excellent tracking resistance without lowering the phenol resin molding material.

[0005]

The present invention comprises 25 to 40% by weight of a phenolic resin containing a resole type phenolic resin as an essential component, and 200% by weight as a filler.
45 to 65% by weight of an inorganic filler mainly composed of an inorganic filler that releases water of crystallization at a temperature of not less than 5 ° C, and an organic filler of 5 to 1%.
Phenolic resin molding material characterized by containing 0% by weight.

[0006] The resole type phenol resin used here is a commonly used resin, and dimethylene ether type resole resin, methylol type resole resin and the like can be used. If necessary, a novolak-type phenol resin may be used in combination, but the total amount of the phenol resin must be 40% by weight or less, and if it exceeds 40% by weight, there arises a problem that the tracking resistance decreases. Novolak type phenolic resin is 50% of the total phenolic resin.
% By weight or less. If it exceeds 50% by weight, the curability is lowered, which is not preferred.

[0007] The main component of the inorganic filler is one that releases water of crystallization above 200 ° C. Examples of such an inorganic filler include aluminum hydroxide, magnesium hydroxide, zinc borate, calcium borate, talc, sepiolite, and the like. The amount of the inorganic filler added is 4
It is preferably 0 to 65% by weight, and the amount of the inorganic filler that releases water of crystallization at 200 ° C or more is preferably 40% by weight or more based on the whole molding material. If it is less than this, heat resistance and tracking resistance will be reduced, and if it exceeds this, the fluidity of the material will be poor and there will be a problem that good moldability as a phenolic resin molding material cannot be exhibited.

As the organic filler, wood flour, pulverized laminate, etc. are used.
Pulp is preferred for improving the mechanical strength of the molded article. The addition amount is 5 to 10% by weight, more preferably 5 to 7% by weight. If the content exceeds 10% by weight, the tracking resistance is reduced. If the content is less than 5% by weight, the tracking resistance is imparted, but there is a problem that the molded product becomes hard and brittle and the mechanical strength is reduced.

The phenolic resin molding material of the present invention is prepared by adding pigments, release agents, curing agents, curing accelerators and the like used in ordinary phenolic resin molding materials in addition to these compounding compositions, and homogenizing these raw materials. After mixing, the mixture is heated and kneaded by a kneader such as a roll, a co-kneader, a twin-screw extruder or the like, and then pulverized to be manufactured.

[0010]

EXAMPLE A molding material was obtained by heating and kneading with a usual two-roll mill in the composition shown in the examples and comparative examples in the upper column of Table 1. The characteristics of the molded article were measured for these molding materials, and the results shown in the lower column of Table 1 were obtained.

[0011]

[Table 1] Resol type phenol resin: use dimethylene ether type phenol resin

(Measurement method) Flexural strength: JIS K 6911 2. 2. Charpy impact strength: JIS K 7111 3. Load deflection temperature: JIS K 7207 Tracking resistance: JIS C 2134

[0013]

As is clear from the above examples, the phenolic resin molding material of the present invention is excellent in heat resistance and tracking resistance in the molded product obtained therefrom, and is required to be used in the electric and electronic devices where these characteristics are required. Suitable for parts.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08K 3:22 3:34)

Claims (4)

[Claims] 1. A phenol resin containing a resole type phenol resin as a main component as an essential component in an amount of 20 to 40% by weight.
A phenol containing 45-60% by weight of an inorganic filler mainly composed of an inorganic filler that releases water of crystallization at 200 ° C. or more, and 5-10% by weight of an organic filler as a filler. Resin molding material. 2. The phenolic resin molding material according to claim 1, wherein hexamethylenetetramine is not contained as a curing agent. 3. The phenolic resin molding material according to claim 1, wherein the phenolic resin contains novolak type phenolic resin in an amount of 50% by weight or less. 4. The phenolic resin molding material according to claim 1, which contains at least 60% by weight of an inorganic filler that releases water of crystallization at 200 ° C. or higher as the inorganic filler.