Toray Industries, Inc.

Sumitomo Electric Industries, Limited

Satoshi Horiuchi

Kenji Hayashi

Takayoshi Akamatsu

Tetsuo Oka

Ryosuke Hata

Masayuki Hirose

Kenji Tsunashima

Shosuke Yamanouchi

Toshiya Yoshii

A vertical magnetic recording medium is prepared by a process for vacuum-depositing a metal selected from cobalt and iron to form a magnetic layer on a substrate, wherein an oxygen gas and at least one gas chemically inactive in the vacuum deposition system, which is selected from nitrogen, argon, helium, neon, xenon, radon, methane and ethane, are introduced into the vacuum to an extent such that the pressure in the vicinity of the substrate is 1.times.10.sup.-3 to 5.times.10.sup.-2 Torr.

Process for preparation of vertical magnetic recording medium

A vertical magnetic recording medium comprising a substrate and a magnetic layer formed on the substrate and having a magnetic anisotropy in the direction vertical to the surface of the substrate is described. The magnetic layer is composed substantially of a metal selected from cobalt and/or iron, and an oxide of the metal. The metal and metal oxide consist of columnar structures oriented in the direction vertical to the surface of the substrate and spaced from one another through fine voids throughout the magnetic layer. The columnar structures have a diameter of 100 to 1000 .ANG. and the magnetic layer have a void ratio of to 56%. The vertical magnetic recording medium is prepared by a process for vacuum-depositing a metal selected from cobalt and iron to form a magnetic layer on a substrate, wherein an oxygen gas and at least one gas chemically inactive in the vacuum deposition system, which is selected from nitrogen, argon, helium, neon, xenon, radon, methane and ethane, are introduced into the vacuum to an extent such that the pressure in the vicinity of the substrate is 1.times.10.sup.-3 to 5.times.10.sup.-2 Torr.

Vertical magnetic recording medium

An oil-immersion electrically insulated cable of high performance is constructed by wrapping a conductor with insulation formed by winding on the conductor polypropylene film having a density in the range of 0.905 to 0.915 g/cm.sup.3, a birefringence in the range of 0.020 to 0.035, a ratio of strengths in two axial directions (tensile strength in the longitudinal direction/tensile strength in the lateral direction) in the range of 5 to 15, and impregnating the insulating layer with an insulating oil, preferably DDB oil.

Electric power cable

Growing community of inventors

Otsu, Japan

Satoshi Horiuchi