JPS5849734A - Flame-retardant resin composition for electric insulation - Google Patents

Abstract

PURPOSE:A composition that is made by adding glass beads to a thermoplastic resin containing a flame retarder, thus bending suitable for the use as a support for switch metal parts which may get wet with water, because of its high antitracking and heat-resistant properties. CONSTITUTION:100pts.wt. of a flame-retardant thermoplastic resin which has a flame retardancy grade of higher than 94V-1 according to the UL standard by addition of a flame retarder are combined with 1-50pts.wt. of glass beads. The glass beads have a particle size distribution ranging from 3 to 500mu and are treated on their surfaces with, e.g., a silane coupling agent.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flame-retardant resin composition for electrical insulation with excellent tracking resistance, which can be applied to switches that are likely to be submerged in water, such as washing machines, dishwashers, dryers, etc. KjiP switches used for kitchen appliances, etc.
The aim is to improve the tracking resistance and heat resistance of the insulating plastic used to support the live parts.

In general, plastic materials are often used to insulate and support live parts. Plastic ivy material Fi for electrical insulation,
In addition to insulation performance, heat resistance and tracking resistance are required. .

41. Since power switches used in washing machines and the like are often used outdoors, the washing machine body is exposed to wind and rain, and is exposed to environments such as direct sunlight in summer and freezing conditions in winter. Therefore, regarding heat resistance performance, the temperature f at which a plastic molded product starts to take on a voice shape must be at least 120 °C.
It is required that no cracks or cracks occur at ℃.

In addition, there are some cases where it is placed in a high temperature environment such as a washing machine or a bathroom, and its moisture resistance is extremely hygroscopic.
In addition, materials that do not absorb moisture and cause insulation deterioration are required;
There is a risk that the power switch may get wet due to water from wind and rain, dew condensation at high temperatures, or when the washing machine is directly exposed to water when operating the washing machine. This can lead to conflicts between departments, which can lead to plastic explosions and fires. In addition, the plastic material is flame resistant, such as Underwriters Laboratories Inc. Item 94 (tlL?41
) It is required to have flame resistance rated at 947-1 class or higher in the direct combustion test specified by K.

As detailed above, power switches that can get wet with water, such as washing machines, have tracking resistance.

Flame separation performance and heat resistance are required.

The present invention provides an electrically insulating plastic material that satisfies these strict requirements, and by using the material of the present invention as a supporting material for a live part, a high-performance switch can be obtained.

Various studies have been conducted on methods for making thermosetting resins flame retardant, and many proposals have been made. Generally, as a flame retardant,
A method is used in which flame retardance is imparted by using a single compound or a combination of two or more of a carbon compound, an inorganic compound, and a phosphor compound.

It is unavoidable that these flame-retardant thermoplastic resins will have lower electrical performance compared to before they were made flame-retardant due to the additives added to them to impart flame-retardancy. Regarding the tracking performance due to the wet method at 0 tatami, the decrease is significant.
Many restrictions had to be placed on product design, which was possible with conventional non-combustible resins. Furthermore, since these additives reduce heat resistance performance, glass fibers are often added to plastics to improve heat resistance performance, but thermoplastic plastics containing glass fibers are often burned. In other words, glass fiber acts as a wick in a candle flame and assists the combustion of plastic.In other words, when glass fiber is added to improve heat resistance, the combustion performance tends to decrease.

From this point of view, the present inventors have developed
As a result of extensive research to prevent the tracking resistance of highly flame-retardant thermoplastic resins from deteriorating, we found that by adding 1 to 50 parts by weight of glass beads to 9,100 parts by weight of flame-retardant resin, Tracking performance has been significantly improved,
We discovered that it also improved heat resistance, and developed 11K1.
It is one food.

The flame-retardant resin composition for electric insulation, which has excellent tracking resistance, of the present invention is useful as a support for a live metal part of a switch, such as a switch for washing and warming up, which is likely to get wet with water. Of course, there are many cases where it can be effectively used as a molding material for other electrical insulation.

As for the flame retardant resin used for Zero-Hatsu@, does it have flame retardancy in the flame resistance test in UXa94 consideration? It is necessary that the flame retardant resin is 4V-1 or higher and is 411114, and the resin constituting the flame retardant resin is acryl tetranitrile-butadiene-styrene ternary typical synthetic resin II (Muis ),
Mainly contains acrylonitrile-styrene typical resin Il (mus), methyl methacrylate antibacterial O copolymer resin, polypropylene, modified poly7-ethylene oxide, polybutylene terephthalate, vinyl chloride and its copolymer resin, and Component polymer blends can be used.

As other blend components, thermosetting resins such as epoxy resins in thermoplastic resins such as polycarbonate, polyethylene tereate, polyarylene ester, polyarylene ester, etc., other than those mentioned above, are used.

What is the flame resistance rating of these resins measured by No. 0194? As a method to increase the flame retardant to 4V-1 or higher, there is a method of adding a commonly used flame retardant,
Chiha four-gen compound, #1 machine compound.

A method is used in which flame retardance is imparted by blending a single substance or a combination of two or more phosphorus compounds, etc. Also, what is commonly referred to as glass beads is small, true spherical glass, and the particle size is Most of the voices are distributed in the Sm2O3 voice range WIK, and what is worse than the SOO voice is the physical properties of the molded material.
41, which is not preferable because it causes a decrease in impact resistance.

The glass beads may be surface-treated with a silane coupling agent or an organic timenate coupling agent or by a known method to prevent bonding with plastic.

According to the present invention, the effect of blending glass beads is remarkable)
Although the details of its mechanism of action are currently not clear, it is probably due to the following reasons.

(1) Due to the spherical beads, molding distortion of the molded product is reduced compared to glass edge wire compositions.

A molded product containing glass fiber has one end of the glass fiber bulging out on the surface, which is then coated with a thin layer of resin. In other words, molded product 0
Table II is moldy and porous. When an arc hits the surface of a molded product in a solid state, the thin film of resin on the surface of the glass fiber carbonizes and crystallizes, resulting in a decrease in tracking resistance. On the other hand, when glass beads are blended, the surface of the molded product is relatively smooth at a blending amount up to sO weight, and it seems that the carbonization of the surface resin due to the rounding arc is reduced4. The amount of beads blended is 1 to 1 part by weight of SO per 100 parts by weight of the flame-retardant thermodustable resin composition.If it is less than 1 part by weight, the improvement in tracking resistance will not be sufficient; If it exceeds this value, it is not preferable because the thermal properties of the thermoplastic resin, especially its impact resistance and fluidity during molding, will be seriously reduced.

The most preferable blending amount is 1 to ISO weight.

There is no particular restriction on the preparation method of the composition from scratch, and the tumbler
Appropriate distribution methods can be adopted, such as the method using a vacuum cleaner, super electric shock absorber, Nauta-kenkisa, Banbury (mixer, kneader, etc.), roll method, melt extrusion method, etc., of course. The composition of the invention may optionally contain various additives used in conventional thermoplastic resins, such as ultraviolet absorbers, softeners, colorants, fillers, and lubricants.

Stabilizers may be added, and a small amount of glass fiber may also be added to improve heat resistance and rigidity.

The present invention will be explained in more detail below with reference to Examples and Comparative Examples, but the scope of the present invention is not limited thereby.
'& O. Performance evaluation of the molded sample can be carried out using the following method.

'(1) Flame resistance test Underwriters - Laboratory - Item 94 (019
A flame resistance test was conducted according to the standard No. 4). However, the dimensions of the test piece are 12A x 12.7 x 1.6 (thickness: 17
16 inches) was used to measure five test pieces.
UL? The flame resistance was rated according to the criteria specified in No. 4.

0) Tracking Resistance Test A tracking resistance test was conducted in accordance with Publication No. 112. However, the washing machine's select switch (
Assuming that the material is used in the 11th II and fall), the voltage applied between the electrodes is 200 V,
Furthermore, as an electrolytic solution, the same standard calls for dropping 0.1 ammonium chloride aqueous solution o. The interval was shortened to 415 seconds, and p was evaluated based on the time it took for the test piece to ignite.

(5) Heat resistance test The thermal deformation am was measured according to the test method specified in M8TM D 44B. However, the test piece is 127×12,
Using 4 pieces of 7x4.4m, I made 7 threads.
Is, 4] #151'', and the specimens were not annealed before measurement.

Examples 1 to S and Comparative Examples 1 to 2 High rigidity! 1511111 (Sevian 7120 manufactured by Daicel Chemical Industries, Ltd.) 100 parts by weight, halogenated organic compound, chlorinated polyethylene, and antimony dioxide in specified amounts as shown in Table 1 were blended into a 90% container, and then boiled in a drum blender. After heating at 1, the cylinder temperature [2! After kneading and pelletizing at 0°C, test pieces were prepared using an injection molding machine with a cylinder temperature of 220°C.The test pieces were tested for flame resistance and tracking resistance. The test was conducted. The results are shown in Table 1.

Application Example The structure of a switch using the material of Example 2 is shown in FIG. 1, and this switch is connected as shown in 2s.

Hall 111ec*, 1 is a fixed spring plate 2 and a movable spring l
The base is an insulating support that supports the l1s. 4 is a button that insulates the movable spring 1 [s. This button 4 is linked to the opening and closing of the fk (S not shown). @ and 6 are fixed and movable bars I[! , mK is a fixed open contact and forms the main part of the live part,! A and ia are fixed and movable spring plate 1.50 terminals, and 7 is a switch glue board.

Figure 2 is a circuit diagram for connecting the switch, and 8 is the plug for powering on, ! is a load such as a switch having the above structure, a motor, a heater, etc.

In the above configuration, the AC voltage 20 is applied to the power supply bladder 8.
Add 0 ma and load 1oKle when switch 9's I1g is applied.
Set the tL current to 2m, then switch! The tracking resistance of the company that opened the following is 0).

First, a 410% acinium chloride molten casing of 11 degrees Celsius is dropped onto the base 410 spring plate 2#S of the switch 9. As a result, when Pase 1 was formed using the composition shown in Comparative Example 2, it ignited in about 1 hour, but according to the composition of Example 2, although it carbonized, it did not ignite. There wasn't.

As described above, according to the present invention, by molding glass beads into a resin, the p% tracking resistance and heat resistance can be significantly improved, and the molded surface is even and rich in gloss.

In addition, by applying such a composition as a support material that supports the live part of the switch, even if the switch is exposed to dew condensation or wetness due to water, IfO damage to the support surface due to tracking can be prevented. Furthermore, it is possible to prevent the occurrence of ignition etc. due to this, improving safety and reliability4! It is possible to significantly improve I, and at the same time, it is possible to realize switch O flame retardancy.

[Brief explanation of the drawing]

The first panel is a perspective view of the external appearance of the switch in the present Vt0-implementation, and the second panel is an electrical circuit diagram showing an example of its use. 1...Base (insulating support)%6, 4...Contact (
Main parts of live parts) Patent applicant: Matsushita Electric Power Co., Ltd. Kinsha Kanbayashi Seisakusho Oka Meishiru Kagaku Kuwa Co., Ltd. Kinshadai Hiroto Furuya - Figure 1 Figure 2

Claims (1)

[Claims] 10.111 A flame retardant thermoplastic resin with a constant υL944Fc and a flame resistance rating of 947-1 or higher is added to 100 weight parts of a flame-retardant thermoplastic resin.
A flame-retardant resin composition for electrical insulation, characterized in that it contains 50 parts by weight.