PURPOSE: To improve flame resistance and wear resistance by making an insulator in a 2-layer construction constituted of an internal layer and an external layer each having a specific composition and setting the ratio of thickness of the internal layer to the external layer within a specific range.
CONSTITUTION: An insulator is made up in a two-layer construction of an internal layer (a) and an external layer (b). The internal layer (a) is constituted of a composition of metal oxide and polyolefine at such a ratio as 50-150 parts by weight of metal oxide to 100 parts by weight of polyolefine. The external layer (b) is constituted of a composition of ethylene copolymer containing vinyl acetate, ester acrylate, etc., at 10wt.% or more and an admixture made up of metal hydroxide and calcium aluminate mixed at such ratio as 100 parts by weight of the ethylene copolymer to 100-300 parts by weight of the admixture. The insulator is made up such that the ratio of the external layer (b) to the internal layer (a) in thickness, b/a, becomes 5/95-50/50. According to a wire made up of an insulator composed as above, the wire is good in flame resistance and no halogen gas is generated at the time of combustion. Also, it holds a value which can fully satisfy the requirements for mechanical characteristics and water resistance.
TANMACHI MASAMI
TAKAHATA NORIO
JPS59211914A | 1984-11-30 | |||
JPS6065059A | 1985-04-13 | |||
JPS6339939A | 1988-02-20 |
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