JPS6080117A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To improve the still-life characteristic of a titled medium by providing a backing layer consisting of a nonorganic material under a ferromagnetic thin metallic film on a substrate and a surfactant layer on the thin film. CONSTITUTION:A backing layer 12 consisting of a nonorganic material such as Mg, Pt, Ni, Cr, and glass is formed on a substrate 11 consisting of a high polymer film, and separated thin films 13 consisting of a ferromagnetic metal such as Fe, Co, and Ni are formed thereon. A surfactant layer 15 of palmitic acid, stearic acid, etc. is formed on the thin film 13. Since the backing layer 12 is provided, the bond strength of the ferromagnetic metal is increased. In addition, since the surfactant layer 15 is provided on the surface, the still-life characteristic can be improved.

Description

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

Recently, thin film type magnetic recording media such as magnetic tapes have come into use. This is a ferromagnetic metal thin film formed by attaching a ferromagnetic metal to a substrate using a vacuum evaporation method, ion blating method, etc. It is characterized by a much higher recording density than later versions.

By the way, when a ferromagnetic metal 2 is attached to a substrate 1 such as a polymer film, as shown in FIG. It may become. Ferromagnetic gold B with this structure
2 has a narrow contact area with the base 1 and has a small contact area. Therefore, when running as a magnetic tape or the like, the magnetic head rubs the ferromagnetic metal thin film, and the ferromagnetic metal 2 easily peels off, which hinders the improvement of steel life characteristics.

In view of the above points, the present invention aims to provide a magnetic recording medium with improved steel life characteristics.

In order to achieve the above object, the present invention provides a magnetic recording medium having a thin film of ferromagnetic metal having a separated structure on a base.
Third, there is provided a magnetic recording medium characterized in that it has an underlayer made of an inorganic material provided on the surface of a substrate.

Further, in order to achieve the above object, the present invention provides a magnetic recording medium in which a thin film of ferromagnetic metal having a separated structure is provided on a substrate, an underlayer made of an inorganic substance provided on the surface of the substrate, The present invention provides a magnetic recording medium characterized by having a surfactant layer provided on the surface of a ferromagnetic metal.

The invention will be explained below in Q) based on the illustrated embodiments.

In FIG. 2, reference numeral 11 is a substrate made of a polymer film such as a polyester film or a polytetrafluoroethylene film. Reference numeral 12 denotes a ground layer made of an inorganic substance provided on one surface of the base 11, and includes magnesium, platinum, nickel, aluminum, chromium, glass,
It is formed by coating or vapor depositing a non-organic substance such as silver. 1
3 is a ferromagnetic metal thin film attached to the base ff112, and is formed by depositing a ferromagnetic metal such as iron, cobalt, or nickel by vacuum evaporation, ion blating, sputtering, or the like. In particular, the individual ferromagnetic metals 14 forming this ferromagnetic metal thin film 13 are
It has a structure in which 11 layers are separated from each other and attached to the base layer 12.

That is, according to the present invention, since the ferromagnetic metal 14 does not exist (it is attached to the underlying layer 12 made of a real substance), it is directly attached to the base layer 12.
Compared to the case where it is attached to No. 1, the attached strength is greater and the steel life characteristics are improved.

Further, FIG. 3 shows another embodiment of the present invention, and the same parts as in FIG. 2 are designated by the same numbers.

In this embodiment, in particular, a surfactant layer 15 is provided on the surface of each ferromagnetic metal 14. Examples of surfactants include higher fatty acids such as palmitic acid, stearic acid, araxic acid, and behenic acid, higher alcohols such as stearyl alcohol, aliphatic amines such as araxinamide, and aliphatic sulfones such as stearyl sulfonate. Use salts and esters such as Then, a solution in which this surfactant is dissolved in a solvent is applied, and it is soaked between the ferromagnetic metals 14 by heating or using ultrasonic waves, or it is immersed in a molten solution of the surfactant. Further, the surfactant layer 15 is formed by vapor deposition using ion bombardment, ion blating, or the like.

According to this invention, similar to the invention shown in FIG. 2, the adhesion strength of the ferromagnetic gold 1m14 is improved, and since the surfactant layer 15 is provided on the surface of each ferromagnetic metal 14, This improves lubricity and increases resistance when rubbed by magnetic heads, etc., further improving steel life characteristics. Further, unlike the case where a part of the surface of the ferromagnetic metal 16 is simply coated with a surfactant layer 17 as shown in FIG. 4, the moisture resistance is improved and the ferromagnetic metal thin film is less likely to rust.

For example, Example A of the present invention, in which a base layer is formed by vapor-depositing aluminum on a polyester film, and cobalt is vacuum-deposited diagonally on the surface of this base layer to form a ferromagnetic metal thin film with a 11-1 II structure; Steel life characteristics were determined for Example B of the present invention, in which a surfactant layer was formed by coating stearic acid on the surface of a ferromagnetic metal, and a conventional example, in which a ferromagnetic metal thin film made of cobalt was formed directly on a polyester film. Upon measurement, the results shown in the graph shown in FIG. 5 were obtained. As is clear from this graph,
The time it takes for the output to drop to 1/2 of the initial value is approximately 71 minutes for Example A of the present invention, approximately 61 minutes for Example B of the present invention, and approximately 2.6 minutes for Conventional Example C. It is clear that the invention improves steel life properties. Also,
Compared to conventional example C, the initial output of example A of the present invention is also about 1.
8 times, and Example B of the present invention is about 1.6 times.

As described above, according to the present invention, it is possible to obtain a magnetic recording medium with improved steel life characteristics.

[Brief explanation of drawings]

FIG. 1 is a front sectional view of a conventional magnetic recording medium, FIG. 2 is a front sectional view of an embodiment of the present invention, FIG. 3 is a front sectional view of another embodiment of the present invention, and FIG. 4 is a comparative example. IF plane sectional view of 5th
The figure shows a graph of steel life characteristics. 11...Substrate, 12...Underlayer, 13...Ferromagnetic metal thin film, 14.16...Ferromagnetic metal, 15.17...Surfactant layer. Patent applicant Hitachi Capacitor Co., Ltd. Figure 1 Figure 2 Figure 1 SIA 8 Figure 4 7

Claims (2)

[Claims] (1) A magnetic recording medium in which a thin film of ferromagnetic metal having a separated structure is provided on a substrate, characterized in that it has an underlayer made of an inorganic substance provided on the surface of the substrate. (2) In a magnetic recording medium in which a thin film of ferromagnetic metal with a separate structure is disposed on a substrate, an underlayer made of an inorganic substance is provided on the surface of the substrate, and an underlayer (
) A magnetic recording medium comprising a surfactant layer.