JPH0353383Y2 - - Google Patents

Description

[Detailed explanation of the invention] (1) [Background and purpose of the invention] The present invention relates to flame-retardant insulated wires for use in wiring circuits of fire prevention equipment, etc., and in particular to wires made of halogen-free materials. be.

Conventionally, materials containing halogens such as polyvinyl chloride were used for the exterior of insulated wires or power cables, but such materials generate combustion gas that is harmful to the human body in the event of a fire, causing damage in the event of a fire. This was the cause of the increase. On the other hand, materials such as polyethylene that do not contain halogen have also been used, but such materials are flammable and thus increase the spread of fire in the event of a fire. For this reason, materials that do not contain halogen and have a large amount of metal oxide added as a flame retardant are used. However, if the exterior part of the wire contains a large amount of metal oxide, it may cause damage if the exterior part of the wire is damaged. There was a problem in that the parts became white, the appearance was impaired, and the commercial value of the product was significantly reduced.

The purpose of the present invention is to solve the above-mentioned conventional problems and provide a high-quality flame-retardant electric wire.

(2) [Summary of the invention] This invention forms the exterior of the electric wire with a material that contains a large amount of flame retardant and does not contain halogen, and the surface of the wire is
This is a flame-retardant insulated wire that contains a small amount of flame retardant and is coated with a material that does not contain halogen and does not impair flame retardancy. In other words, an insulating layer is provided on the conductor, an exterior that contains a large amount of flame retardant and does not contain halogen is provided, and a surface that contains a small amount of flame retardant and does not contain halogen so as not to turn white even if the surrounding area is scratched. This is a flame-retardant insulated wire formed by providing layers.

The exterior of the wire contains a large amount of metal oxide as a flame retardant, so in the event of a fire, it protects the internal conductor without the risk of fire spreading, and the exterior surface only contains a small amount of metal oxide, so it does not get scratched. Even if scratches occur, the scratches do not remain white and there is no major change in appearance.

(3) [Examples] Examples of the present invention will be described below with reference to the attached drawings.

FIG. 1 is a sectional view of a flame-retardant electric wire according to an embodiment of the present invention. An electric wire is formed by twisting three wire cores each consisting of a conductor 1 covered with an insulator 2, filling the space around them with an arbitrary inclusion 3, and wrapping a tape 4 around the outer periphery. It is covered with exterior 5. The exterior casing 5 is made of, for example, a mixture of 100 to 200 parts by weight of a metal oxide to 100 parts by weight of an ethylene polymer, and contains a large amount of flame retardant, but hardly any halogen.
The outer periphery of the exterior 5 contains a small amount of flame retardant to the extent that it does not turn white even if it is scratched. Specifically, for example, 80 parts by weight of a metal oxide is added to 100 parts by weight of the ethylene polymer. A surface layer 6 containing the following is provided. The amount of metal oxide contained in this surface layer 6 is reduced as long as it does not impair flame retardancy,
Its thickness is preferably 0.1 to 0.3 mm.

(4) [Effect of the invention] Since the electric wire of the present invention contains a small amount of flame retardant in the surface layer of the exterior, even if the outer periphery of the electric wire is scratched, it will not turn white and spoil the appearance. Without,
Moreover, since the exterior contains a large amount of flame retardant, it is difficult to burn in the event of a fire and can prevent the spread of fire.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the electric wire of the present invention. Codes in the diagram: 1...Conductor, 2...Insulator, 3...
Inclusion, 4...Tape, 5...Exterior, 6...Surface layer.

Claims (1)

[Scope of utility model registration request] In an insulated wire in which an insulating layer 2 is provided on a conductor 1, and a covering layer is further provided to cover this,
The above-mentioned coating layer includes an exterior 5 that contains a large amount of flame retardant and does not contain halogen, and a casing 5 that contains a small amount of flame retardant and halogen to the extent that it does not turn white even if it is scratched and is formed around this exterior 5. 1. A flame-retardant insulated wire characterized by comprising a surface layer 6 that does not burn.