JPS63102025A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To improve a preserving characteristic by using a Co-Cr alloy contg. 3-10wt% Pr to form a perpendicularly magnetized film formed on a high- polymer film. CONSTITUTION:The perpendicularly magnetized film 3 formed on the high- polymer film 1 is constituted of the Co-Cr alloy contg. 3-10at% Pr. Then, Pr contributes to an improvement in the crystallinity and to the formation of an oxide film denser the film of Cr and, therefore, magnetic sepn., the noise at the time of high density recording and reproduction and an error rate are improved. The high density of the oxide film leads to an improvement in the preserving characteristic and the satisfactory characteristic is maintained even before and after the preservation.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording medium for perpendicular magnetic recording suitable for high-density magnetic recording.

Conventional technology A new perpendicular magnetic recording method is attracting attention as a magnetic recording technology that will lead to higher density in the next generation [Foreign journal: IEE Transactions on Magnetics, <
(IEEE TRANSACTIONS MAG
NET I C3) To l, MAG-13, //
a5, I), p.

1272-1277 (1977)).

In perpendicular recording, an antiparallel magnetization transition perpendicular to the medium surface is formed, so the magnetization transition becomes extremely narrow and extremely high density recording is possible. Therefore, it is important to establish mass production technology for media that satisfies both durability and signal-to-noise ratio (hereinafter referred to as C/N) [Applied Magnetics Seminar, Perpendicular Magnetic Recording Methods 2]. (December 1960)].

The perpendicular magnetization film is formed by sputtering method [Japan Society of Applied Magnetics, 39th Research Meeting Materials P, 31 (1985)]
1 Electron beam evaporation method [Journal of the Institute of Electronics and Communication Engineers, Je6-1
．． This method can be carried out using methods such as J. 1, P. 65 (1983), and Qo-Cr films are mainly being studied.

T1 is added as a third element to Co-Cr for the purpose of improving magnetic properties or to obtain magnetic properties at low temperatures (Japanese Unexamined Patent Publication No. 5G-14617)t Pt
(Japanese Unexamined Patent Publication No. 59-11605), P
(Japanese Unexamined Patent Publication No. 59-17215) and Mn (Japanese Unexamined Patent Publication No. 59-61012) have been proposed.

Problems to be Solved by the Invention However, although the above configuration can initially satisfy the improvement in characteristics, the characteristics deteriorate after being stored in various temperature and humidity environments, and further improvement is desired. It was. The present invention was made in view of the above-mentioned circumstances, and provides a magnetic recording medium with improved storage characteristics and a good error rate.

Means for Solving the Problems In order to solve the above-mentioned problems, the magnetic recording medium of the present invention has a perpendicular magnetization film formed on a polymer film of 3% to
It is composed of a Qo-Or gold alloy containing 10 at% Pr.

The magnetic recording medium of the present invention has the above-described structure, and since Pr improves crystallinity and forms a denser oxide film than Cr, 1 magnetic separation is improved, and noise during high-density recording and reproduction is improved. and improve the error rate. In addition, the above-mentioned dense oxide film has the power to improve storage characteristics, and good characteristics are maintained both before and after storage.

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The figure is an enlarged sectional view of the magnetic recording medium of the present invention. In the figure, 1 is a polymer film made of polyethylene terephthalate, polyphenylene sulfide, and polyether sulfonate. It can be selected from polycarbonate, polyamideimide, polyethylene naphthalate, polyimide, etc. 2 is an undercoat layer, which can be considered as a polymer film including this, but not all applications require this component, so if necessary, a fine particle coating layer or a worm-like raised layer may be applied. You can select from among them and optimize it.

3 is a Co-Cr-Pr perpendicular magnetization film, and Pr is preferably in the range of 3aj% to 10at%. Cr may be distributed after determining Pr in order to dilute the magnetism of CO to enable perpendicular magnetization. If pr is less than 31Lt%, the improvement effect of addition, especially the improvement of storage properties, will not be sufficient, so 3a
t% or more is required, but since a system containing IQ&t% or more will have a lower magnetic property, this range is appropriate. Although it is easy to obtain a perpendicularly magnetized film using a sputtering method, it is also possible to obtain a perpendicularly magnetized film with good reproducibility by using an electron beam evaporation method using multiple evaporation sources if the conditions are sufficiently set; however, there are no particular limitations on the characteristics depending on the manufacturing method. There isn't.

4 is a protective lubricating film, which is a coating or vapor deposition film of fatty acid, fatty acid amide, fluorine compound, etc., or a plasma polymerized film.

The film may be appropriately selected from a carbon film, an oxide film, a nitride film, etc. alone or in combination.

Of course, it may be in the shape of a magnetic tape or in the form of a 9-disk.

An example of more specific comparison data is shown below.

12 pieces/(μm) of CrO2 particles with a particle size of 12Q were placed on a polyethylene terephthalate film with a thickness of 12 μm.
) 13 fine particle coating layer fixed with 2 polyester resin
．． After performing oxygen glow discharge treatment at 56 (MHz) and 2 (KW) for 1.6 (seconds), a Co-cr-pr gold alloy target was used as a Co-cr-pr gold alloy target and 0.16 μm was formed by high-frequency sputtering at 13.56 (MHz). A perpendicularly magnetized film was formed on the film, zinc stearate was vacuum-deposited at 6° on the film, and a magnetic film with a width of 8 mm was formed after the film was flattened.

It was flat.

Using a ferrite head with a gap length of 0.15 μm,
Recording and reproduction were performed with a bit length of 0.26 μm, and characteristics were compared. The error rate and C/N were compared. Storage environment is 60°C 90%
RH and Toshida.

The characteristics and manufacturing conditions are shown below.

(Hereinafter, blank space) 7/E-7 Special opening UG3-102025 (3) Effects of the invention As described above, according to the present invention, the storage characteristics are good and the C/E-7
N, there is an excellent effect that a magnetic recording medium for perpendicular magnetic recording with an excellent error rate can be obtained.

[Brief explanation of the drawing]

The figure is an enlarged sectional view of a main part of an embodiment of the magnetic recording medium of the present invention. 1... Polymer film, 3... Co-Or-
Pr perpendicular magnetization film.

Claims (1)

[Claims] A magnetic recording medium characterized in that a perpendicularly magnetized film formed on a polymer film is made of a Co-Cr alloy containing Pr in an amount of 10 at% or less and 3% or more.