JPH10330583A - Phenolic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a phenolic resin compsn. which is excellent in resistances to moisture and heat, flame retardance, and electrical characteristics though it does not contain a halogenous flame retardant by compounding a phenol- formaldehyde resin as the major ingredient with flame retardants comprising an inorg. filler capable of dissociating water of crystallization and melamine cyanurate. SOLUTION: This compsn. is prepd. by compounding 100 pts.wt. phenol- formaldehyde resin with, as flame retardants, 5-20 pts.wt. inorg. filler capable of dissociating water of crystallization (e.g. boric acid, aluminum hydroxide, zinc borate, magnesium hydroxide, or talc) and 3-20 pts.wt. melamine cyanurate. Usually, a novolak phenolic resin is used as the phenol-formaldehyde resin, and hexamethylenetetramine is used as the curative. The joint use of an inorg. filler capable of dissociating water of crystallization and melamine cyanurate draws out the characteristics of both the flame retardants and synergistically improves the flame retardance of the compsn.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to water resistance, flame retardancy,
The present invention relates to a phenol resin composition which provides a phenol molding material having excellent electrical properties. Particularly, the present invention relates to a phenol resin composition suitable for electric parts.

[0002]

2. Description of the Related Art Conventionally, phenolic resin molding materials have been:
Used in various electronic components. Such components are required to have properties such as dimensional stability against moisture, heat resistance, flame retardancy, and high strength. In particular, as electronic components have recently become smaller and thinner, heat resistance and flame retardancy of thin molded products have been required. In general, phenolic resin has self-extinguishing properties, and a molded product with high flame retardancy can be obtained, but when it is made into a thin molded product, the flame retardancy tends to decrease, and in order to improve the flame retardancy, And inorganic fillers containing water of crystallization, flame retardants such as phosphates, and flame retardants containing halogen elements such as chlorine and bromine.

[0003]

However, when many of these flame retardants are added in a large amount, the specific gravity of a molded product becomes high, bleeding occurs, the appearance becomes poor, and moisture resistance and heat resistance decrease. Or, if a flame retardant containing a halogen element is added, there are problems such as the generation of dioxin and the deterioration of the global environment when incinerated after disposal.
There is a limit to its use in electronic component applications. The present invention is a flame retardant containing no halogen element, a phenol resin composition excellent in moisture resistance, heat resistance, flame retardancy, electric properties, and suitable for molding electronic components, and a phenol resin molding material using the same. The purpose is to provide.

[0004]

SUMMARY OF THE INVENTION The present invention is a phenolic resin composition comprising a phenolic formaldehyde resin as a main component and an inorganic filler capable of dissociating water of crystallization as a flame retardant and melamine cyanurate. It is a phenol resin composition containing 5 to 20 parts by weight of an inorganic filler that dissociates water of crystallization and 3 to 20 parts by weight of melamine cyanurate with respect to 100 parts by weight. Further, the present invention, the phenolic formaldehyde resin is a novolak type phenolic resin,
A phenol resin composition containing hexamethylenetetramine as a curing agent is preferred.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is a phenol resin composition characterized in that the resin component is a phenol formaldehyde resin and contains an inorganic filler that dissociates water of crystallization as a flame retardant and melamine cyanurate,
The phenolic formaldehyde resin is not particularly limited, but usually a novolak type phenol resin is used, and hexamethylenetetramine is used as a curing agent. In particular, when heat resistance is required, a resol-type phenol resin can be used in combination.

Examples of the inorganic filler that dissociates water of crystallization used as the flame retardant of the present invention include boric acid, aluminum hydroxide, zinc borate, magnesium hydroxide, talc and the like. The amount of the inorganic filler that dissociates the crystallization water is preferably 5 to 20 parts by weight based on 100 parts by weight of the phenolic formaldehyde resin. Especially preferably, it is 10 parts by weight or less. Even if it is added in an amount exceeding 20 parts by weight, no further improvement in flame retardancy is observed, and the specific gravity of the molded product is increased or the moldability is deteriorated. On the other hand, if the amount is less than 5 parts by weight, the effect of the flame retardancy is so small that the object cannot be achieved.

The main purpose of the melamine cyanurate used in the present invention is to impart flame retardancy, and those having various particle sizes can be used. Specifically, MC-410, MC-440, MC-610, and M-410 manufactured by Nissan Chemical Industries, Ltd.
C-640 and the like. The smaller the particle size, the better the appearance of the molded article is, which is preferable. Melamine cyanurate is
Since it has a high heat loss temperature and excellent heat resistance, and also has good resistance to water, it is suitable for improving heat resistance and moisture resistance. The mechanism of flame retardation of melamine cyanurate is considered to be a cooling effect of the system by an endothermic reaction at the time of decomposition of the compound. The decomposition temperature of melamine cyanurate in air is as high as 430 ° C., which is effective when used together with an inorganic filler that dissociates and releases water of crystallization at a lower temperature than achieving flame retardancy alone.

In the present invention, by using an inorganic filler that dissociates water of crystallization and melamine cyanurate in combination as a flame retardant, the characteristics of the flame retardant can be brought out, and the flame retardancy is synergistically improved. In addition, characteristics required for electric components such as moisture resistance and heat resistance are not reduced.

In order to use the phenolic resin composition of the present invention as a molding material, an organic filler such as pulp or wood powder, glass fiber, calcined clay is added to the above resin composition in the same manner as in the case of a usual molding material. , Inorganic fillers such as calcium carbonate,
In addition, slaked lime, pigments, release agents, curing agents and the like are blended.
After uniformly mixing the above raw materials, a molding material can be obtained by kneading with a pressure kneader, a twin screw extruder, a pressure roll, or the like.

[0010] The molding material obtained from the phenolic resin composition of the present invention is excellent in moisture resistance, flame retardancy and electric properties, suitable for molding electronic parts, and has been developed for miniaturization and thinning of electric parts. Can be used in fields where flame retardancy is required. Hereinafter, the present invention will be described specifically with reference to Examples.

[0011]

EXAMPLES A phenolic resin molding material was prepared according to the composition shown in the upper column of Table 1. As a method for producing a molding material, a powder is put into a 12-inch roll (roll surface temperature: 110 ° C.) and kneaded until the spiral flow becomes 30 to 35 mm. The plate-shaped kneaded material is pulverized by a hammer type pulverizer. For each pulverized molding material, a test piece was prepared with an injection molding machine, and the characteristics were measured. The results are shown in the lower column of Table 1.

[0012]

[Table 1] Material name Unit Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Nophorac-type phenolic resin 100 parts by weight 100 100 70 100 70 Resole-type phenolic resin 0 0 30 0 30 Melamine cyanurate MC-440 10 0 15 0 0 Melamine cyanurate MC-610 0 10 0 0 0 Zinc borate 5 0 8 0 0 Boric acid 0 10 0 0 0 Hexamethylenetetramine 15 15 12 15 12 Wood flour 30 30 30 30 30 Pulp 10 40 60 10 60 Fired clay 60 40 10 60 10 Release agent, pigment 8 8 8 8 8 Molded product characteristics Unit
Water absorption% 0.4 0.4 0.45 0.65
0.82 Insulation resistance (normal) Ω 1.0 × 1.2 × 1.1 × 3.4 × 2.1 × 10 ¹⁴ 10 ¹⁴ 10 ¹⁴ 10 ¹³ 10 ¹² Insulation resistance (D-2 / 100) Ω 1.5 × 1.5 × 1.6 × 6.6 × 3.8 × 10 ¹² 10 ¹² 10 ¹² 10 ¹¹ 10 ¹⁰ Heat deformation temperature ℃ 180 180 190 180 190 Soldering heat resistance% 4 4 5 8 8.5 Flame retardancy (0.4mm) V-0 V-0 V-0 V-1 V-1

The measurement was performed as follows.
The water absorption, insulation resistance, and heat deformation temperature are as specified in JIS K691.
Performed according to 1. The solder heat resistance was determined by immersing a test piece having a diameter of 50 mm and a thickness of 3 mm in a solder bath at 400 ° C. for 3 seconds, and measuring the rate of change in thickness. The flame retardancy is 12.
A test piece having a thickness of 7 × 127 × 0.4 mm was measured according to the UL94 vertical method.

From Table 1, it can be seen that Examples 1 to 4 of the present invention in which an inorganic filler for dissociating water of crystallization according to the present invention and melamine cyanurate were blended.
No. 3 is UL94 despite its thickness being as thin as 0.4 mm.
V-0 and excellent flame retardancy. Moreover, the solder heat resistance is superior to the comparative example in which the flame retardant is not blended.
Also, the water absorption is low. Also, the insulation resistance is excellent by one to two orders of magnitude compared to the comparative example in which no flame retardant is blended, and shows good electrical properties. On the other hand, Comparative Examples 1 and 2 in which no flame retardant was blended were UL9
4 V-1 and is inferior in flame retardancy, and is also inferior in water absorption, insulation resistance and solder heat resistance.

[0015]

Industrial Applicability The phenolic resin composition of the present invention has excellent moisture resistance, flame retardancy, and electrical properties, and is suitably used for molded articles requiring these properties, particularly for electronic parts. Further, the phenolic resin composition achieves flame retardancy without containing a halogen element, is effective for maintaining the global environment, and is environmentally friendly.

Claims (3)

[Claims] 1. A phenolic resin composition comprising a phenolic formaldehyde resin as a main component and an inorganic filler which dissociates water of crystallization as a flame retardant and melamine cyanurate. 2. A phenolic formaldehyde resin 100.
5 parts by weight of inorganic filler that dissociates water of crystallization
The phenolic resin composition according to claim 1, comprising 20 parts by weight and 3 to 20 parts by weight of melamine cyanurate. 3. The phenolic resin composition according to claim 1, wherein the phenolic formaldehyde resin is a novolak type phenolic resin and contains hexamethylenetetramine as a curing agent.