Fuji Photo Film Company, Limited

Kunihiko Honda

Masaaki Fujiyama

Tsutomu Okita

Kiyomi Ejiri

Ryuji Shirahata

Akihiro Matsufuji

Toshio Ishida

Hiroaki Araki

Kazuyuki Usuki

Toshihiko Miura

Hideomi Watanabe

Mikio Ohno

Tadashi Ishiguro

Tadashi Ishikuro

Masatoshi Kiyama

Masataka Ohta

A magnetic recording medium having a magnetic recording layer on at least one surface of a non-magnetic support, wherein the magnetic recording layer has thereon a lubricant layer containing at least one fluoroalkyl sulfo compound having an ether or ester linkage, which is represented by the following formula (1). The magnetic recording medium is free from corrosion of the magnetic recording layer and has a low coefficient of friction and excellent running durability and shelf stability. The lubricant layer is particularly suitable for a magnetic recording medium having a metal thin film with or without an inorganic protective film as a magnetic recording layer.

Magnetic recording medium having a lubricant layer of a fluoroalkyl

A method for making a magnetic recording medium comprises the steps of mixing ferromagnetic grains and a surface treating agent, grinding the resulting mixture, and thus obtaining a ground mixture. A binder and a solvent are added to the ground mixture, which results from the mixing and grinding process, the resulting mixture is kneaded and diluted, and a kneaded and diluted mixture is thus obtained. An additive and a solvent are then added to the kneaded and diluted mixture, which results from the kneading and diluting process, a dispersion process is carried out on the resulting mixture, and a dispersion mixture is thereby obtained. Thereafter the dispersion mixture, which results from the dispersion process, is applied to a non-magnetic substrate.

Method for making magnetic recording media

A process for the preparation of a magnetic recording disk comprises the steps of providing a magnetic recording layer on a surface of a nonmagnetic support, punching the nonmagnetic support together with the magnetic recording layer into a disk having a circular hole in its central portion, and fitting mechanical members including a center core made of a synthetic resin into the hole of the support. The nonmagnetic support having the magnetic recording layer and at least the center core of the mechanical members are subjected to heat treatment independently prior to fitting the mechanical members including the center core into the hole of the support.

Process for the preparation of magnetic recording disk

A magnetic recording medium is described, having improved carrier noise ratio and weather resistance, by controlling the content and the crystal size of iron nitride which contains iron oxide or .epsilon.-Fe.sub.x N (2&lt;x.ltoreq.3).

Magnetic recording medium

A method is described for preparing a magnetic recording medium by vapor-depositing a magnetic metal thin film on a polyester film, which comprises winding up a polyester film while subjecting the polyester film to a tension of from 0.1 to 2.0 kg/mm.sup.2, heating the resulting polyester film roll at 60.degree. C. to 80.degree. C. for from 10 to 100 hours, and vapor-depositing a magnetic thin film onto the polyester film while subjecting the polyester film to a tension of 0.5 kg/mm.sup.2 or more.

Method for preparing a magnetic recording medium

Growing community of inventors

Kanagawa, Japan

Kunihiko Honda