JPS587704A - Semiconductive composition for power cable - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a semiconductive adhesive for electrical cables which prevents discoloration and corrosion at the interface between the conductive metal inner and outer shield metals in contact with the semiconductive layer. 4 related matters 1-
1 Generally, electric cables are provided with an inner 5siI layer and an outer semiconductive layer, but due to the structure of the cable,
The inner S#P conductive layer contacts the conductive metal, and the outer semiconductive layer contacts the outer shield metal. On the other hand, the materials used for the semiconductive layer are usually ffA, Elum, ethylene-propylene rubber, ethylene-α-olefin copolymer, or a paste resin blended with other resins and conductive carbon. things are being used.

However, in the cable using the above composition, chemical reaction occurs at the interface between the inner semiconducting layer and the conductor metal or the outer semiconducting layer and the outer shielding metal under the long-term product term. As the corrosion progresses, the conductor and shield may become discolored, corrosion may worsen, and cable characteristics may deteriorate.

The present invention has been developed to address the above-mentioned disadvantages in appearance4, and to provide a semiconductive composition for a power cable that prevents discoloration and corrosion at the interface between the semiconductive layer and the conductor metal or outer shield metal. It is to provide supplies.

A feature of the present invention is that a compound containing a triazole group is blended into the semiconductive composition.

Examples of compounds containing a triazole group used here include benzotriazole, mef, benzotriazole, 5-(N-salicyloyl)amino-1,2,4-
) Riazole can be used. The blending amount is preferably in the range of 0.001 to 1 part by weight per 100 parts by weight of the rubber or glass material of the semiconductive composition.

That is, even if more than 1 part by weight is added, the #)tυ effect will not be improved and it is not preferable from a cost standpoint, so the above range is sufficient.

9. Even if anti-aging agents, processing aids, and peroxide cross-linking agents are added as necessary, the discoloration and corrosion prevention effect will not be affected.

The reason why it is possible to obtain a semiconductive composition that prevents discoloration and corrosion of conductor metals and outer shield metals by incorporating such triazole group-containing compounds is that this compound can be used in the following manner. This is because it is inferred that it functions as follows. In other words, the O compound coordinates with the metal and forms a thin and durable structure. This protective film is chemically stable enough to protect the internal SO gold metal from external chemical attack and prevent the progression of corrosion reactions, and is thin enough to prevent electrical contact with low resistance. This is because the rubber and plastic materials used in the semiconductive composition are IVA, as in the past.

EEA, ethylene-propylene rubber, ethylene-α olefin copolymer, or a blend of these with other resins can be used, and it is preferable to use these t-base resins and mix conductive carbon with them.

Examples of the present invention will be described below.

As a CV cable, cross-sectional area 50-O soft copper strand-conductor, 3
An insulating layer of uncrosslinked polyethylene extrusion tested with a thickness of 0.
A cable with a 1-inch thick mild steel shielding tape and a sheath layer made of extruded soft polyvinyl chloride is extruded with various external semiconductive layers shown in the table below, and 614/d
A sample was prepared by heating and crosslinking with O saturated steam. These test samples 1') were immersed in hot water at 11-70°C for 3 months, then disassembled and visually observed for discoloration and corrosion.

For comparison, a similar cable without the compound containing seven triazole groups was also produced as a comparative example.

As is clear from Table 0, a semiconducting layer containing a triazole group-containing compound was applied to the inside El of the mild steel shielding tape.
It can be seen that the tape metal does not undergo any corrosion during discoloration when the temperature is 100%. On the other hand, it can be seen that if the conductive layer O is not mixed with a conventional lyazole group-containing compound, corrosion during discoloration cannot be prevented.

In the above embodiments, the outer conductive layer is provided, but this is not limited to this, and if applied to the inner conductive layer, the effect of preventing discoloration and corrosion of the conductive metal will be obtained.
4 hours until you say what you can get. Moreover, the semiconductive layer is not limited to the case where the semiconductive layer is formed by extrusion, but it is also possible to form the semiconductive layer by applying the conductive composition of the present invention in the form of a film.

Above I! - As is clear from the present invention, the medium conductivity m
Since it contains a compound containing a lyazole fundamental sound, when an internal and/or external semiconducting layer is provided with this composition, even under long-term use and high concentration conditions,
It is possible to obtain an excellent power cable in which the conductor metal and the outer shield metal do not discolor or corrode.

Patent developer Fujikura Denkoji Co., Ltd.

Claims (1)

[Claims] A medium conductive composition for an electric cable, which contains 0.001 to 1 part by weight per 100 parts by weight of t4I mold.