JPH04368715A - Abrasion-resistant electric wire - Google Patents

Abstract

PURPOSE:To provide an electric wire for a vehicle covered with an insulating material which is fire-resistant, generates no hydrogen halogenide if burnt, has excellent abrasion resistance, and can be changed into many colors. CONSTITUTION:A composition material 2 added with at least one of a metal hydrate 30-200 pts.wt. and red phosphorus 3-50 pts.wt. within the range 30-200 pts.wt. for the total of the metal hydrate and red phosphorus to a copolymer 100 pts.wt. of alpha-olefin and ethylene with the Shore D hardness 50 or above is covered around conductors 1 to form an electric wire for a vehicle.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] This invention relates to electric wires that can be used in transportation means such as automobiles and ships, and industrial machines such as elevators and robots, and in particular, although they are flame retardant, they do not generate toxic gases even when incinerated. This invention relates to wear-resistant electric wires that suppress the generation of smoke.

0002

[Prior art] Automotive wires are made of polyvinyl chloride (PV).
C) Insulating materials mainly composed of (for example, PVC resin,
Mixtures of fillers, plasticizers and stabilizers) are often used. However, such halogen-containing materials generate toxic hydrogen halide gas and large amounts of smoke when burned, so they pose problems in the event of a fire and its disposal from the standpoint of the impact on the human body and the environment. It has become to. For this reason, for example, it is desirable to recover and reuse the insulating material of automobile electric wires after they are scrapped, without incinerating them. However, since automotive electrical wires are intricately arranged in the car body with thin wires and wires of different lengths, it is extremely difficult to separate only the electrical wires when dismantling the vehicle and collect and reuse the insulating material, including PVC. It is difficult to In reality, when disposing of automobiles, these electric wires and the like are often disposed of by incineration or landfill. If a large amount of PVC is incinerated, it will directly cause problems such as air pollution due to hydrogen chloride gas, and indirectly cause problems such as corrosion of processing equipment due to hydrogen chloride gas, resulting in high processing costs. It will be. Furthermore, as land shortages become more and more serious, the cost of disposing of waste through landfill is high and cannot be continued in the future. These problems are likely to become more serious as the number of scrapped cars increases.

On the other hand, for cables and electric wires used in public facilities, insulating materials that do not generate hydrogen halide gas and generate little smoke when burned have traditionally been used from the standpoint of disaster prevention. , flame-retardant wires have been developed. As such an insulating material, for example, Japanese Patent Application Laid-open No. 5
No. 1-46341 discloses a composition in which aluminum hydroxide, magnesium hydroxide, or a composite of magnesium hydroxide and magnesium carbonate is blended with a thermoplastic resin, and further fine carbon powder is added. In addition, JP-A-57
-92037 discloses a composition in which a hydrate of an inorganic metal compound and a red phosphorus flame retardant are added to a polyolefin resin.

0004

These compositions are insulating materials that impart flame retardancy to electric wires and do not generate hydrogen halide when burned. However, when a conductor is coated with these materials to make automotive wires, there is a risk that the coating will wear out significantly due to friction with the vehicle body or parts during assembly, or friction with the vehicle body or other wires during use. was there. In this way, the electric wire using the above flame retardant material is
Poor abrasion resistance required for automotive wires.

Furthermore, since fine carbon powder is added to the composition disclosed in JP-A-51-46341, the electric wire coated with this material becomes black, and it is impossible to color it with other colors. Very difficult. Automobile harnesses need to be multicolored for identification, and from this point of view, the above-mentioned materials containing fine carbon powder are inappropriate.

The purpose of the present invention is to solve the above-mentioned problems, and to provide an insulating material coated with an insulating material that is flame retardant, does not generate hydrogen halide during combustion, has excellent abrasion resistance, and can be multi-colored. The object of the present invention is to provide electric wires, especially electric wires for automobiles.

[0007]

[Means for Solving the Problems] A wear-resistant electric wire according to the present invention is an electric wire having wear resistance so that it can be installed in a vehicle, and is made of a copolymer of α-olefin and ethylene and has a Shore D hardness of 50 or more. 100 parts by weight of metal hydrate, 3 parts by weight
A composition obtained by adding at least one of 0 to 200 parts by weight and 3 to 50 parts by weight of red phosphorus within the range of a total of 30 to 200 parts by weight of the metal hydrate and the red phosphorus is used as a conductor. It is characterized by being coated.

[0008] The copolymer of α-olefin and ethylene according to the present invention is produced, for example, when the α-olefin has 4 carbon atoms.
, 6, or 8 linear low-density polyethylene and very low-density polyethylene.

[0009] The metal hydrate according to the present invention is, for example,
Contains aluminum hydroxide, magnesium hydroxide, calcium hydroxide and mixtures thereof.

[0010] The composition according to the present invention may contain anti-aging agents, antioxidants, vulcanizing agents, plasticizers, colorants, flame retardant aids, etc., if necessary.

[0011]

[Operation] According to the present invention, by adding at least one of a metal hydrate and red phosphorus to a copolymer of α-olefin and ethylene with a Shore D hardness of 50 or more, flame retardancy and good properties are achieved. A composition having wear resistance is provided. In this composition, in particular, by setting the Shore D hardness of the copolymer of α-olefin and ethylene to 50, high wear resistance is imparted to the composition. If this hardness is less than 50, it will not be possible to obtain sufficiently satisfactory wear resistance as an electric wire for automobiles.

[0012] Metal hydrates also act as flame retardants. The reason why the metal hydrate is set at 30 to 200 parts by weight is that if the amount added is less than 30 parts by weight, a sufficient flame retardant effect cannot be obtained, and if it exceeds 200 parts by weight, the moldability of the composition may deteriorate and breakage may occur. This is because mechanical strength such as strength and abrasion resistance decreases.

Furthermore, the flame retardant effect can be further enhanced by adding red phosphorus. By using metal hydrate and red phosphorus together, the flame retardant effect can be further enhanced. The reason why red phosphorus is set at 3 to 50 parts by weight is that if the amount added is less than 3 parts by weight, the flame retardant effect will be weak, and if it exceeds 50 parts by weight, the mechanical strength such as breaking strength and abrasion resistance of the composition will decrease. Because it does.

[0014] Also, the total of metal hydrate and red phosphorus is 30
The range of ~200 parts by weight is because if the total is less than 30 parts by weight, a sufficient flame retardant effect will not be obtained, and if it is more than 200 parts by weight, the mechanical strength such as breaking strength and abrasion resistance of the composition will deteriorate. This is because it decreases.

[0015] By coating the periphery of a conductor with the composition described above, it is possible to provide an electric wire that is flame retardant and has excellent abrasion resistance. Moreover, since the above-mentioned composition does not contain a halogen compound, even if the electric wire according to the present invention is incinerated, it does not generate hydrogen halide and generates little smoke. Further, since the above composition does not contain carbon, it can be colored by adding a coloring agent or the like. Therefore, an electric wire coated with this composition can be multicolored.

[0016]

[Example] Seven annealed copper wires with a diameter of 0.32 mmφ are twisted together to give a conductor cross-sectional area of 0.5 mm2, and the periphery is coated with a material whose composition is shown in Table 1 by weight ratio, and the coating is extruded to a coating thickness of 0.5 mm2. We made a prototype of 3mm electric wire for automobiles. FIG. 1 is a cross-sectional view of a prototype electric wire. As shown in the figure, a covering 2 of an insulating material is provided around the twisted conductor 1.

In Table 1, compositions according to the present invention are shown in Invention Examples 1 to 8, and conventional examples using PVC are shown in Conventional Example 1. Comparative Example 1 is an example in which a copolymer of α-olefin and ethylene with a low Shore D hardness of 42 is used, and Comparative Example 1 is an example in which the composition ratio is outside the scope of this invention according to the present invention. 2-7. The compositions shown in Table 1 are prepared by melt-kneading the components according to conventional methods. The trade name and manufacturer of each component are shown in the margin of Table 1.

It should be noted that anti-aging agents, antioxidants, vulcanizing agents, plasticizers, coloring agents and other flame retardant aids may be added to the above composition as required.

[0019]

[Table 1]

[0020] Automotive electric wires coated with the compositions shown in Table 1 as described above were tested for wear resistance, breaking strength,
Tests were conducted on flame retardancy and amount of hydrogen chloride generated during combustion. The results of the test are shown in the bottom column of Table 1. Moreover, the test method is as shown below.

[0021] Abrasion resistance...as shown in Figure 2, approximately 10c
A load of 714 g was applied on the m-long electric wire sample 3.
．． A metal rod 4 with a diameter of 5 mm is placed orthogonally. Then, the metal rod 4 is moved at a speed of 60 reciprocations per minute to wear out the wire sample 3. The number of reciprocations of the metal rod 4 until the metal rod 4 is electrically connected to the conductor 1 of the wire sample 3 is defined as the wear resistance index. It is desirable that this index be 300 or more.

[0022] Breaking strength: Complies with JIS C3005. It is desirable that the result is 1.6 kg/mm2 or more.

Flame retardancy: According to JIS K7201 oxygen index method. It is desirable that the result is 26 or more.

Amount of hydrogen chloride generated: According to JCS C No. 53. As shown in Table 1, Examples 1 to 8 of the present invention have good breaking strength, wear resistance, and flame retardancy, and do not generate hydrogen chloride during combustion.

[0025]

As explained above, the electric wire according to the present invention is flame retardant, does not generate toxic hydrogen halide gas when burned, and generates little smoke. In addition, the electric wire according to the present invention has excellent abrasion resistance, and the insulating material can be made of multiple colors easily. Therefore, the present invention is particularly useful for electric wires for automobiles, and is also effective when used as electric wires for use in transportation machines such as motorcycles and ships, and industrial machines such as elevators, cranes, and robots.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an electric wire formed in an embodiment of the invention.

FIG. 2 is a schematic diagram showing an apparatus for testing the abrasion resistance of electric wires in Examples.

Claims (1)

[Claims] Claim 1: A wear-resistant electric wire that can be installed in a vehicle, comprising 100 parts by weight of a copolymer of α-olefin and ethylene with a Shore D hardness of 50 or more, and 30 to 200 parts by weight of a metal hydrate. A conductor is coated with a composition in which at least one of 3 to 50 parts by weight of the metal hydrate and the red phosphorus is added in a range of 30 to 200 parts by weight. Automotive electric wire featuring: