JPH0342573Y2 - - Google Patents

Description

[Detailed explanation of the idea]

The present invention relates to an insulated wire with good flame retardancy. In recent years, with the spread of TVs and audio equipment, there has been an increasing demand for flame-retardant electric wires used in the equipment to prevent fire accidents from electrical products. For this reason, thermoplastic resins containing halogen in the molecular structure, such as polyvinyl chloride and chlorinated polyethylene, or halogen-based flame retardants, such as chlorinated paraffin, are used as insulators for electrical wires for internal wiring in equipment, such as polyethylene and ethylene vinyl acetate. A material added to a halogen-free thermoplastic resin such as a polymer is used. On the other hand, UL is a well-known standard applied to insulated wires for internal wiring used in TVs, audio equipment, etc.
Standards (Undercuriters Laboratories Ine. Standards)
There is. The flame retardant test standards of this UL standard are very strict, and the UL standard also includes a heat aging tensile test, a heat aging wrapping test, etc., so it is necessary to satisfy these tests at the same time. There are various grades of this UL standard, and recently the requirements for flame retardancy have become more and more stringent, so it has become impossible to satisfy the requirements with the conventional combination of conductor and insulator materials. We investigated various combinations of conductor and insulator materials, but the combination of conventional bare copper wire or tin-plated copper wire and polyethylene insulating material added with halogen flame retardant was aged at 158℃ for 168 hours or
It was found that a cylindrical sample with the conductor removed passed the test after aging at 136°C for 60 days, but a wire sample failed. It was also found that this tendency becomes more pronounced as the insulation thickness becomes thinner, less than 0.6 mm. In another experiment, it was found that an insulator made of polyethylene to which only an anti-aging agent was added without the addition of a halogen flame retardant did not pass the flame retardancy test, but did pass the aging test described above. Based on this, we thought that the conductor material might have some influence on the insulator material, and after careful consideration, we found that if we use nickel-plated copper wire and thermoplastic resin with halogen flame retardant added, we could create a thin wall with an insulation thickness of 0.6 mm or less. It was found that the effect was particularly great in this case, passing not only the above-mentioned aging test but also all tests including the flame retardant test. The reason for this effect is that bare copper wire and tin-plated copper wire cannot prevent deterioration of the insulator due to the effect of copper ions on halogen flame retardants, but in the case of nickel, copper ions block it. It seems likely that it will be done. The present invention is characterized in that an insulator made of thermoplastic resin containing a halogen flame retardant is provided on a conductor made of nickel-plated copper wire to a thickness of 0.6 mm or less. Figure 1 shows an example of the invention. 1 indicates a conductor, and 2 indicates an insulator. The conductor may be a single wire or a stranded wire, and in the case of a stranded wire, the nickel plating can be applied to the stranded wire or after the stranded wire, or both. Examples and comparative examples will be described below. In Examples 1 and 2, an insulator having the composition shown in Table 1 was applied to a nickel-plated copper wire with an outer diameter of 0.83 mm to a thickness of 0.6 mm.
mm (Example-1) and 0.4 mm (Example-2) were extrusion coated and irradiated with an electron beam of 20 Mrad. Also, comparative examples-1, 2, and 3 have an outer diameter of 0.83
Insulators having the composition shown in Table 1 are applied to bare electric wires with thicknesses of 0.8 mm (Comparative Example-1), 0.6 mm (Comparative Example-2), and 0.4 mm (Comparative Example-2), respectively.
mm (Comparative Example-3), each insulated wire was extruded coated and irradiated with an electron beam of 20 Mrad. Comparative Example 4 is an insulated wire in which a nickel-plated copper wire with an outer diameter of 0.83 mm is extruded and coated with an insulator having the composition shown in Table 1 to a thickness of 0.8 mm, and is irradiated with an electron beam of 20 Mrad. Two types of insulating compositions were used for each type, so a total of 12 types of insulated wires were made.For each, a cylindrical sample with the conductor pulled out and a wire sample were prepared, and the cylindrical sample was heated at 158℃ for 168 hours. It was aged in a gear oven under two conditions at 136°C for 60 days, and then subjected to a tensile test using an Instron sample machine. In addition, a wire-shaped sample was subjected to a self-winding test after aging under the conditions described above, and another sample was subjected to a flame resistance test based on the UL standard. As a result, all the flame resistance tests were good, and the other results are as shown in Table 2. When the insulation thickness was 0.6 mm or less, Comparative Examples 2 and 3 using bare copper wire failed the self-diameter winding test after aging, whereas Example 1 using nickel-plated copper wire, In the case of 2, it can be seen that even if the insulation thickness is 0.6 mm or less, it passes the test. As mentioned above, the insulated wire of the present invention is a nickel-plated copper wire coated with a thermoplastic resin containing a halogen flame retardant to a thickness of 0.6 mm or less, so even though the thickness of the insulator is thin, it does not deteriorate after aging. It performs well in tensile tests, post-aging self-diameter winding tests, and flame resistance tests, making it ideal for wiring electrical wires for TV audio equipment, etc.

【table】

【table】 [Brief explanation of the drawing]

FIG. 1 shows an embodiment of the insulated wire of the present invention, where 1 indicates a nickel-plated conductor (single wire or stranded wire), and 2 indicates an insulator.

Claims (1)

[Scope of utility model registration request] An insulator made of a thermoplastic resin containing a halogen flame retardant is placed on a conductor made of nickel-plated copper wire.
An insulated wire characterized by having a thickness of 0.6 mm or less.