Fujikura Limited

Nof Corporation

Toshio Niwa

Toru Takahashi

Tohru Takahashi

Michio Takaoka

Shotaro Yoshida

Motoyuki Ono

Tsuneaki Motai

Kazuhiko Goto

Hiroshi Yamanouchi

Kenji Matsui

Shiro Nakayama

Izumi Ishikawa

Keiichiro Kataoka

Mitutaka Tanida

Thoru Nakatsuka

Hiroyuki Miyata

A polyethylene composition which is useful in insulations and joints of extra-high voltage power cables, and in which a cross-linking agent, comprising an organic peroxide subjected to purification processing, and an antioxidant, are blended, wherein the cross-linked composition has a dielectric loss tangent (tan.delta.) of less than or equal to 0.07% at a temperature of 90.degree. C. and under an electric field stress of 20 kV/mm. This polyethylene composition exhibits little dielectric loss, even at high temperatures or high electric field stresses, and is optimally employed in insulations and joints for extra-high voltage power cables of 275 kV or more.

Polyethylene composition for use in insulations and joints of extra-high

A DC power cable includes a conductor and an insulation of a thermoplastic resin formed around the conductor. The insulation contains carbon black in an amount of about 0.2 to about 5% of the total weight of the thermoplastic resin and the carbon black, and the ratio of mineral oil absorption (cc/100 g) to specific surface (m.sup.2 /g) in the carbon black is not less than 0.7. The carbon black has the hydrogen content of not more than 0.6% by weight. The specific surface is measured by BET equation. The carbon black has a particle size of 10 to 100 nm.

DC electric power cable

Growing community of inventors

Yachiyo, Japan

Toshio Niwa