JPH0438424Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to flame-retardant cables used as electric wires for electronic equipment, electric wires for vehicles, electric wires for ships, or other coated electric wires, power cables, communication cables, etc. It is something.

[Conventional technology]

Insulating coating materials for electronic equipment wires, vehicle wires, marine wires, and other wires and cables are designed to have flexibility and mechanical properties to withstand wiring work and normal operation under harsh conditions. It is required to have excellent heat resistance and flame retardancy.

Many of the conventional flame retardant compositions are made flame retardant by adding halogen-based flame retardants, which has the problem of generating a large amount of harmful halogen-containing gas when burned. Therefore, there is a strong demand for halogen-free, in other words, low-pollution flame retardant compositions. Various types of polyolefin flame-retardant compositions having excellent flexibility and mechanical properties and flame-retardant cables coated with the compositions have been developed.

[Problems that need to be solved]

Incidentally, in order to wire flame-retardant cables accurately and efficiently inside devices with complicated internal structures, it is required to color-code the cables.

Cables can be color-coded by incorporating pigments into the outermost layer of the cable, such as the insulating layer or sheath. However, mixing pigments, which are usually used in very small amounts, uniformly into the organic polymer compositions that make up these layers is disadvantageous in terms of work efficiency and power consumption, and also poses the problem of the troublesome management of the pigments.

On the other hand, the method of using a master batch of pigments is advantageous in terms of work efficiency and material management, but the organic polymer composition to be colored is a polyolefin flame-retardant composition containing a non-halogen flame retardant. In the case of polyolefin, a large amount of the flame retardant mentioned above is usually blended to make the flammable polyolefin sufficiently flame retardant, and when a pigment masterbatch is mixed with this, the organic polymer in the masterbatch makes it non-halogen. There is a problem that the content of the flame retardant is diluted and the flame retardancy is reduced.

[Means for solving problems]

The present invention aims to provide a flame-retardant cable that is easy to manufacture and solves the above-mentioned problems.

That is, in the present invention, a conductor is coated with an organic polymer layer mainly composed of a specific copolymer made flame retardant with a non-halogenated flame retardant, and further coated with the above-mentioned organic polymer layer containing a pigment, etc. The present invention relates to a flame-retardant cable characterized by having a color-differentiated skin layer made of a copolymer.

[Action and effect]

Separately from the organic polymer layer that has been made flame retardant with a non-halogenated flame retardant, by providing a separate color-coding skin layer on top of it, the above-mentioned flame-retardant organic polymer layer does not need to be color-coded. The above-mentioned problem is eventually solved. In addition, the color-specific skin layer is sufficient if it is extremely thin and only has to perform the function of each color, so it is not necessarily necessary to make the layer flame retardant. Even when used for formation, problems such as a decrease in flame retardancy do not occur.

〔Example〕

1 and 2 are cross-sectional views of embodiments of the present invention, in which 1 is a conductor, 2 is an organic polymer layer made flame retardant with a non-halogen flame retardant, and 3 is a color-coded layer. This is the skin layer. In the embodiment of FIG.
The organic polymer layer 2 is an insulating layer that also serves as a sheath, and in the embodiment shown in FIG.
It consists of an insulating layer 21 provided directly above the insulating layer 21 and a sheath 22 provided thereon. insulating layer 21,
Both the sheath 22 are made of a composition in which the same or different organic polymers are made flame retardant with a non-halogen flame retardant.

In the present invention, the specific copolymer constituting the organic polymer layer is linear low-density polyethylene (a copolymer of olefin with 4 to 16 carbon atoms and ethylene, with a density of 0.90 to 0.94, melt Substantially linear polyethylene with an index of 0.1 to 20, such as those produced by polymerizing the above-mentioned olefin raw materials in the presence of a catalyst under low pressure) and ethylene-α-olefin Copolymer (a copolymer of ethylene-α-olefin with 4 to 8 carbon atoms and ethylene, with a density of 0.86 to
0.89 and a melt index of 0.5 to 10, preferably polymerized using a Ziegler catalyst). Among the linear low-density polyethylenes mentioned above, those in which the olefin as a copolymer copolymerized with the ethylene chain constituting the polyethylene have about 4 to 10 carbon atoms are preferred, and more specifically, those in which the comonomer has butene-1 , octene
1 and 4-methylpentene-1 are most preferred. Also, among the linear low-density polyethylenes mentioned above, the density measured by ASTM D1505 is about 0.91 to about
A value of 0.94 is preferred. Furthermore, among the above-mentioned linear low-density polyethylenes, the melt index (MFR) measured by ASTM D1238 is about 0.1 to about 10.
Preferred are those having a density of about 0.911 to about 0.925.

Non-halogen flame retardants used in the present invention include alumina hydrates such as aluminum hydroxide,
Hydrates of metal oxides such as magnesium hydroxide and hydrotalcites, metal oxides such as antimony trioxide, antimony pentoxide, titanium dioxide, zinc oxide, magnesium oxide, and aluminum oxide, or zinc borate, carbonic acid Examples include other inorganic flame retardants such as magnesium, or phosphorus-based organic flame retardants such as organic phosphate esters and red phosphorus.

As red phosphorus, a wide range of commercially available products can be used. For example, if the red phosphorus content is
Preferably, the content is 80% by weight or more, the loss on drying is 0.8% by weight or less, and the 74 mesh sieve residue is 7% by weight or less. It is also preferable that the surface of the above-mentioned red phosphorus is coated with a thermosetting resin such as phenol-formalin resin. Specific examples thereof include NOVELETSU 120 and NOVELETSU 120UF (both manufactured by Rin Kagaku Kogyo Co., Ltd.).

The above non-halogen flame retardant is 50% by weight per 100 parts by weight of organic polymer and 100 parts by weight of polyolefin.
It is used in large amounts of up to 200 parts by weight, especially as much as 80 to 150 parts by weight. The material constituting the organic polymer layer 2 may contain an antioxidant such as a copper inhibitor, a hindered phenol antioxidant, or a sulfur antioxidant, if necessary.
A crosslinking agent, a crosslinking aid, or other agents may be added in necessary amounts. The color-differentiated skin layer 3 is formed using a composition in which the above-mentioned copolymer is the same or different from the base polymer of the organic polymer layer 2 and colored with an organic or inorganic pigment or dye. You may do so. The thickness of the color-differentiated skin layer 3 is preferably as thin as possible as long as the cable of the present invention can be identified, for example, about 100 to 500 μm.

[Brief explanation of drawings]

1 and 2 are both cross-sectional views of an embodiment of the present invention, in which 1 is a conductor, 2 is an organic polymer layer which has been made flame retardant with a non-halogen flame retardant, 21 is an insulating layer, 22 is a sheath, and 3 is a color-coded skin layer.

Claims (1)

[Claims for Utility Model Registration] (1) Linear low-density polyethylene (a copolymer of olefin with 4 to 16 carbon atoms and ethylene, with a density of 0.90 to 0.94 and a melt index of 0.1 to
20) or ethylene-α-olefin copolymer (a copolymer of ethylene-α-olefin with 4 to 8 carbon atoms and ethylene, with a density of 0.86 to
The conductor is coated with an organic polymer layer whose main component is 0.89 melt index 0.5 to 10), which is made flame retardant with a non-halogen flame retardant, and further coated with the polyethylene or the copolymer and the pigment. A flame-retardant cable characterized in that it has a color-differentiated skin layer consisting of a color-specific skin layer or a dye. (2) The flame retardant according to claim (1) of the utility model registration, characterized in that the flame retardant is blended in an amount of 50 to 200 parts by weight per 100 parts by weight of the polyethylene or the copolymer. cable.