JPS60223028A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To obtain the magnetic recording medium which can improve still life and has a stable change rate of total magnetic flux quantity, a stable and small coefft. of friction and good runnability by providing a protective layer consisting of higher fatty acid added with halogenated fatty acid to the surface of a thin ferromagnetic metallic film formed on a substrate. CONSTITUTION:The thin ferromagnetic metallic film 2 formed on one surface of the substrate 1 consisting of a high polymer film, etc. is formed by sticking iron, cobalt, nickel or the alloy thereof, etc. by a vacuum deposition method, ion plating method, sputtering method or the like on said substrate. The protective layer 3 to be formed on the surface of the film 2 is formed by coating or depositing by evaporation the higher fatty acid such as behenic acid or the salt thereof or the deriv. thereof to which halogenated fatty acid or paraffin is added.

Description

[Detailed description of the invention] The present invention relates to magnetic recording media.

As a magnetic recording medium such as a magnetic tape, an IR type is used, which has a structure in which a ferromagnetic metal is attached to a substrate such as a Karasu molecule film by a vacuum vaporization method, an ion blating method, etc. to form a ferromagnetic gold M11 film. It has become possible to do so.

By the way, in such a thin film type magnetic recording medium, the ferromagnetic metal thin film is easily corroded, and it is also a problem! In order to make it easier to remove, it is usually coated with high-quality fat or the like on its surface. ! There are layers. However, the conventional Li-retaining layer has a low still life, a large rate of change in total magnetic flux, and #l! It had drawbacks such as a high coefficient of friction and poor running performance.

The object of the present invention is to provide a magnetic recording medium which improves the above-mentioned drawbacks and improves characteristics such as still life.

In order to achieve the above object, the present invention provides a magnetic recording medium in which a ferromagnetic metal thin film and a ferromagnetic thin film are sequentially provided on a substrate, and a protective layer made of higher fatty acids to which halogenated fatty acids are added. The present invention provides a magnetic recording medium characterized by the following.

In addition, in order to achieve the above object, the present invention provides a magnetic recording medium in which a ferromagnetic gold layer and a ferromagnetic gold layer are sequentially provided on a substrate, in which a ferromagnetic gold layer is prepared from higher fatty acids to which halogenated paraffins are added. The present invention provides a magnetic recording medium characterized in that it is provided with a protective layer.

Embodiments of the present invention will be described below based on the drawings.

In FIG. 1, reference numeral 1 indicates a substrate made of a polymer film or the like. 2 is a ferromagnetic metal thin film formed on one surface of the substrate 1, and is formed by depositing iron, cobalt, nickel, or an alloy thereof by vacuum evaporation, ion blating, sputtering, etc. . 3 is a protective layer formed on the surface of this ferromagnetic metal thin film 2, which is made by adding halogenated fatty acids or paraffins to higher fatty acids such as behenic acid, its salts, or its derivatives. It is formed by coating something or by vapor deposition.

The applicant of the present invention has found that the still life, total magnetic flux rate of change, and running properties of the magnetic recording medium 4 are significantly improved by providing the above-mentioned protective layer.

For example, when the still life, the rate of change in total magnetic flux, and the coefficient of friction were measured for the embodiment of the present invention and the conventional example, the results shown in FIGS. 2 to 4 were obtained.

The configurations of the embodiment of the present invention and the conventional example are as follows.

Embodiment (A) of the present invention: (a) Substrate: Polyester film (b) Ferromagnetic metal thin film: Co:Ni = 80:20 alloy formed by vacuum evaporation method.

Added 5% stearic acid substituted with and convert this into alcohol: toluene- Coat a solution dissolved in a 1:1 solution. ing.

Example (B) of the present invention: (c) Protective layer: Stearic acid was used as the higher fatty acid, 5% of paraffins Czz H2q C1,21 with a chlorination rate of 70% was added, and this was mixed with alcohol:toluene=1 = Coated with a solution dissolved in 1.

Conventional example (C) (c) Protective layer...behenic acid with alcohol: toluene-
Coated with a solution dissolved in a 1:1 solution.

Comparing the characteristics of the magnetic recording media constructed as described above, the still life of both embodiments (A) and (B) of the present invention is 50 minutes or more before the output goes out, whereas that of the conventional example. The former is about 6 minutes (improved to more than 8). Also, the rate of change in total magnetic flux is 9 minutes at 60°C.
After being left in an atmosphere of 0% RH for 3 weeks, the present invention example (A
> and (B) are 0.6 to 1.9%, whereas in the conventional example it is 5%, and the former is 40% or less of the latter. Furthermore, regarding the friction coefficient, 30℃, 60%RH
In an atmosphere of
is almost the same as the initial value, 0.5 and 0.45, whereas in the conventional example, the initial value is small at 0.4, but about 20
It is larger than the embodiments (A) and (B) of the present invention in the pass range, and is 0.65 in the case of 100 buses, and it is clear that the former is more stable and smaller.

As described above, according to the present invention, it is possible to obtain a magnetic recording medium that can significantly improve the still life, has a stable total magnetic flux rate of change and a stable friction coefficient, has a small friction coefficient, and has good running properties.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, FIG. 2 is a graph of still life characteristics, FIG. 3 is a graph of total magnetic flux rate of change, and FIG. 4 is a graph of changes in friction coefficient. DESCRIPTION OF SYMBOLS 1... Substrate, 2... Ferromagnetic metal thin film, 3... Protective layer. Patent Applicant: Hitachi Condens V Co., Ltd. Figure 3 Figure 4 Yesterday [Stop] 7. xot

Claims (2)

[Claims] (1) A thin ferromagnetic metal film and a ferromagnetic metal film on the substrate. ! A magnetic recording medium in which layers are sequentially provided, characterized in that a protective layer made of higher fatty acids to which a halogenated fatty acid is added is provided. (2) A magnetic recording medium in which a ferromagnetic gold 1III1 film and a protective layer are sequentially provided on a substrate, characterized in that a protective layer made of higher fatty acids to which halogenated paraffins are added is provided. .