JPS60121520A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To obtain a high-performance magnetic recording medium which has a small coefft. of friction, less sliding noise and is free from clogging and drop-out in the stage of recording and reproducing by providing two protective films consisting of a thin film-like fluoroorg. material layer and a thin film-like org. material layer contg. carbon and hydrogen as an element on the surface of a thin film-like magnetic metallic layer. CONSTITUTION:A thin film-like magnetic metallic layer 5 consisting of Co, Cr, Ni, etc. is provided on a base plate 4 of polyester, etc. and a thin film-like fluoroorg. material layer 6 and a thin film-like org. material layer contg. carbon and hydrogen as an element (for example, ethylene polymer) 7 are formed by a plasma polymn. method on the surface 5 of said layer. The adhesion strength of the layer 7 and the layer 6 is not large and therefore when the magnetic recording medium slides with a magnetic head, post, etc., the org. material 7 contg. carbon and hydrogen as an element slides on the layer 6 and the dirt sticking to the surface of the magnetic recording medium owing to electrification of the layers 6, 7 is simultaneously removed. Clogging and drop-out are thus eliminated in the stage of recording and reproducing.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a magnetic recording medium in which a thin metal magnetic layer is provided on a polyester substrate.Conventional structure and problems thereof In recent years, magnetic recording and reproducing devices have been As devices become smaller, lighter, and have higher density recording, perpendicular recording methods that aim for even higher density are being considered. In response to this, metal evaporated tapes and metal tapes, in which a thin metal magnetic layer is provided on a polyester substrate, are being studied and put into practical use as magnetic recording media.

A conventional magnetic recording medium will be explained below.

FIG. 1 shows a cross-sectional view of a conventional magnetic recording medium, in which 1 is a substrate made of polyester or the like, and 2 is a thin metal magnetic layer. 3 is a protective film that protects the metal magnetic layer from sliding with the magnetic head, post, etc.

Regarding the conventional magnetic recording medium configured as described above,
The operation will be explained below.

The thin metal magnetic layer 2 is formed on the substrate 1 made of polyester or the like by paper deposition of a magnetic metal such as Co, Cr, or Ni by evaporation, ion blasting, or sputtering. It is impossible to use the produced thin-film metal magnetic layer 2 as it is as a magnetic recording medium, and since the thin-film metal magnetic layer 2 directly slides on the magnetic head or guide post, the magnetic head/post cannot be used as it is. Many problems occur, such as abrasion of the thin metal magnetic layer 2, scratches on the thin metal magnetic layer 2, and chirps and squeals caused by stick-slip. For this reason, a protective film 3 is provided on the thin metal magnetic layer 2. Organic materials are commonly used as protective films, and various materials such as stearic acid and lignoceric acid have been studied, but when considering friction coefficient, sliding noise, etc., fluorine-containing organic materials are the best. Attempts have been made to coat perfluorocarboxylic acids of 8 or more by dissolving them in a solvent. As for the coating method, in addition to the above-mentioned wet method in which an organic polymer is dissolved in a solvent and coated, dry methods such as an organic vapor deposition method and a plasma polymerization method are being considered, and the dry method allows for uniform coating. In particular, the protective film produced by plasma polymerization is a uniform film without pinholes and has strong adhesion to the thin metal magnetic layer 2.

However, with the above configuration, the protective film formed of a fluorine-containing organic substance becomes charged due to sliding, etc., and is free from dust in the air, chips generated when slit into tape shapes, and transferred dust from the back surface when rolled up. This has the problem of causing clogging and dropout of the magnetic head during magnetic recording and reproduction.

Purpose of the Invention The present invention solves the above-mentioned conventional problems. It takes advantage of the fluorine-containing organic protective film, which has a small coefficient of friction and little sliding noise, while achieving high performance without clogging or dropouts during recording and playback. The purpose is to provide magnetic recording media.

Structure of the Invention The present invention provides a method for depositing Co-Cr/Ni on a substrate such as polyester.
A magnetic material in which a thin film-like metal magnetic layer is provided, and a thin film-like fluorine-containing organic material layer and a thin film-like organic material layer containing carbon and hydrogen as elements (e.g. ethylene polymer) are formed on the surface of this thin film-like metal magnetic layer by plasma polymerization. It is a recording medium, and by providing an organic layer containing carbon and hydrogen as elements on the fluorine-containing organic layer, when the magnetic recording medium slides on a magnetic head, guide post, etc., carbon and The organic matter made of hydrogen slides and removes dirt adhering to the surface at the same time, which eliminates clogging and dropouts during recording and playback.

DESCRIPTION OF EMBODIMENTS FIG. 2 shows a sectional view of a magnetic recording medium in an embodiment of the present invention. In FIG. 2, 4 is a substrate made of polyester or the like, and 6 is a thin metal magnetic layer. 6 is a thin film-like fluorine-containing organic material layer, and 7 is an organic material layer containing carbon and hydrogen as elements, both of which are protective films.

The operation of the magnetic recording medium of this embodiment configured as described above will be explained below.

Since the thin organic layer 7 containing carbon and hydrogen as elements is provided on the thin fluorine-containing organic layer 6, its adhesion strength is not large. Therefore, when the magnetic recording medium slides against a magnetic head, post, etc., the organic material containing carbon and hydrogen as elements slides on the thin film-like fluorine-containing organic material layer 6. For this reason, dust in the air that adheres to the magnetic recording medium due to the charging of the protective film, chips generated when rinsing the tape, and dust transferred from the back surface when the tape is wound, etc. It is removed as organic substances containing carbon and hydrogen slide.

Therefore, it is possible to improve the smearing and drop-out caused by dirt adhering to the magnetic recording medium. The table below shows the results of repeatedly running a tape-shaped magnetic recording medium with a single layer of fluorine-containing organic material and a tape-shaped magnetic recording medium with a two-layer protective film of a fluorine-containing organic layer and an organic layer containing carbon and hydrogen as elements. Regarding clogging, the total number was taken when the tape-shaped magnetic recording medium was repeatedly run 10 times for 1 pass of 10 minutes, and dropout was taken as the average value per minute when measured under the above conditions.0 Fluorine-containing organic layer and A coating method is generally used to form a carbon/hydrogen organic layer, but a protective layer formed using a plasma polymerization method was more effective. This is thought to be because the coating method causes uneven coating, and when microscopically observed, some areas are not coated at all.The plasma polymerization method can overcome this drawback. Therefore, if a fluorine-containing organic layer and an organic layer containing carbon and hydrogen as elements are formed by plasma polymerization, a uniform protective film with no unevenness can be obtained, resulting in a high-performance magnetic recording medium with less clogging of the magnetic head and less dropout. I can do it.

Effects of the Invention As described above, the magnetic recording medium of the present invention has CO.Cr-N.
A two-layer protective film, a thin fluorine-containing organic layer and a thin organic layer containing carbon and hydrogen as elements, is formed on the surface of a thin metal magnetic layer such as i by plasma polymerization, resulting in a low friction coefficient and low sliding noise. While taking advantage of the advantage of the fluorine-containing organic protective film that there is little fluorine, it is possible to provide a high-performance magnetic recording medium that does not cause clogging or dropout during recording and reproduction, and has great practical effects.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a conventional magnetic recording medium, and FIG. 2 is a cross-sectional view of a magnetic recording medium according to an embodiment of the present invention. 6...Fluorine-containing organic layer, 7... Organic layer containing carbon and hydrogen as elements. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
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Claims (2)

[Claims] (1) A thin metal magnetic layer of Co, Cr, Ni, etc. is provided on a substrate such as polyester, and the surface of the thin metal magnetic layer is coated with a thin fluorine-containing organic layer, and the surface of the thin metal magnetic layer is coated with a thin fluorine-containing organic layer. A magnetic recording medium characterized by having an organic layer containing carbon and hydrogen as elements. (2) The magnetic recording medium according to claim 1, wherein the thin film-like fluorine-containing organic material layer and the organic material layer containing carbon and hydrogen as elements are formed by a plasma polymerization method.