JPS60171625A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To improve the adhesion between a non-magnetic substrate and thin gamma-Fe2O3 magnetic film and to prevent damage such as exfoliation of the magnetic film by providing an intermediate film laminated alternately with >=1 layers of the 1st Ti2O3 film and the 2nd Ti2O3 film by a specific method between the substrate and the magnetic film. CONSTITUTION:A TiO2 film 23 is deposited to 0.02mu thickness on an alumitetreated Al substrate 21 then a Ti film 24 is deposited to 0.1mu thickness on the film 23. A thin alpha-Fe2O3 magnetic film 25 is deposited to a prescribed thickness on the film 24 and thereafter the film is reduced and oxidized at about 300 deg.C by which a magnetic recording medium having the thin magnetic film 25a transformed to gamma-Fe2O3 is formed. The O in the film 23 is taken into the film 24 by such treatment and the film 23 is changed to the Ti2O3 film 23a and the Ti film 24 to the Ti2O3 film 24a by which an intermediate film 22 consisting of the 1st film 23a and the 2nd film 24a is formed. The adhesion strength between the substrate 21 and the magnetic layer 25a is thus improved, and the magnetic disc, etc. having excellent durability without exfoliation, chipping, etc. are obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to the improvement of a magnetic recording medium suitable for high-density recording, and particularly to a highly durable and reliable magnetic recording medium.

(bl Background of the Technology) In recent years, in magnetic disk drives, high-density recording has been achieved by thinning the magnetic recording medium, that is, the magnetic disk, and lowering the flying height of the magnetic head. In addition, for example, when the magnetic head is stopped, the magnetic head is in contact with the surface of the magnetic disk, and due to the airflow that occurs as the rotational speed of the magnetic disk increases,
The so-called C8, which allows the magnetic head to float slightly
The S (Contact 5tart 5top) method is adopted.

However, with this method, when the magnetic disk starts rotating,
Also, since the magnetic head comes into contact with and slides on the surface of the magnetic disk when the magnetic disk is stopped, there is an inconvenience that head crashes such as abrasion and damage to the surface of the magnetic disk are likely to occur. Therefore, in order to prevent such inconveniences, it is common practice to perform surface treatment such as applying or coating the magnetic disk surface with a lubricant made of higher fatty acids, higher fatty acid ester compounds, silicon compounds, etc. .

(C1 Prior Art and Problems By the way, conventional magnetic recording media, such as magnetic disks, are made by direct sputtering, reduction/oxidation treatment, etc. -Since the configuration is adopted in which a magnetic film made of Fe203 is formed, when a lubricant is applied to the surface of this magnetic disk as described above and the magnetic disk is rotated and stopped by the C8S method, the magnetic film is Particularly when the amount of lubricant applied is large, a phenomenon occurs in which the magnetic head is attracted to the surface of the magnetic disk due to the large amount of lubricant applied when the magnetic disk stops, and when the magnetic disk starts rotating. There is a problem that the magnetic film is easily peeled off by the attracted magnetic head, and when the magnetic film is tightly adhered to the non-magnetic substrate and the magnetic disk is rotated or stopped using the CSS method, the magnetic film is easily peeled off. There is a need for a magnetic disk that can sufficiently withstand peeling damage of the magnetic film due to head sliding.

+d) Purpose of the Invention In view of the above-mentioned conventional situation, the present invention has a structure in which a magnetic film is provided on a non-magnetic substrate with an intervening film of titanium or titanium oxide or the like that enhances adhesion, and magnetic film due to head crash etc. The object of the present invention is to provide a highly reliable magnetic recording medium that prevents film peeling and damage.

(la) Structure and object of the invention According to the present invention, γ-
In the magnetic recording medium provided with the Fe203 magnetic thin film, between the nonmagnetic substrate and the r-'Fe203 magnetic thin film,
A structure in which a first titanium sesquioxide film and a second titanium sesquioxide film are alternately laminated in at least one layer with an intermediate film interposed therebetween, and the film thickness of the first titanium sesquioxide film is 0.0.
2 to 0.1 μm, and the thickness of the second titanium sesquioxide film is 0.1 μm.
This is achieved by providing a novel magnetic recording medium characterized by a thickness of 0.05 to 0.2 μm.

(fl Embodiment of the Invention An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view of a main part showing such an embodiment.

In the figure, 1 is an alumite-treated AQ'3F-magnetic substrate, and on the AQ non-magnetic substrate 1, for example, a first titanium sesquioxide (Ti203) film 3 and a second titanium sesquioxide (Ti20a) film are formed. A structure is adopted in which a γ-Fe 2 O, 3 magnetic thin film 5 is provided with an intermediate film 2 consisting of a film 4 interposed therebetween.

Therefore, by configuring the magnetic recording medium as described above, the alumite-treated All nonmagnetic substrate 1
(Al!203) and the first titanium sesquioxide (Ti20
3) Membrane 3 and second titanium sesquioxide (Ti203)
The adhesion between the film 4 and the rFe2O3 magnetic thin film 5 is determined by Lewis acid (an acid defined based on the transfer of electrons, which accepts a pair of electrons and forms a covalent bond with the other party, and one which gives a pair of electrons and shares it with the other party). The strength of the rFe2O3 magnetic thin film 5 to the non-magnetic substrate 1 is significantly improved as can be explained by the theory of Lewis bases.

Furthermore, to further explain the reason why the adhesion of the γ~Fe203 magnetic thin film 5 to the non-magnetic substrate 1 described above is improved using the Lewis acid theory, it can be said that generally one surface of the non-magnetic substrate A (hOsc anodized) is improved. ), the relationship between the Lewis acidity strength of γ-Fe203 (magnetic thin film 5) and Ti203 (intermediate film 2) is A(ho3≧γ-Fe203>>Ti20
It is 8. As for the adhesion between objects with the same Lewis acidity strength, for example, AQ20s and γ-Pe203, since the surface polarities of both are the same, strong adhesion cannot be expected. The strength of is one strong 1tlAQ203 and the other weak T'i2
Regarding the adhesion with '03, it is thought that the surface polarities of both are in an inverse relationship to each other and the electrostatic force acts as a synergistic effect, so that the adhesion between the two becomes extremely strong. Therefore, γ-Fe203 is directly applied to one surface of the AP nonmagnetic substrate (A11203) which has been anodized as in the past.
Providing the magnetic thin film 5 proves that the surface polarity of the two is not compatible and the adhesion is poor.

Next, in order to obtain the magnetic recording medium of the present invention described above, first, as shown in FIG.
A titanium dioxide (Ti02) film 23 with a thickness of 0.02 μm is deposited on the nonmagnetic substrate 21 by sputtering or the like. Subsequently, a titanium (Ti) crotch 24 is deposited on the titanium dioxide (Ti02) film 23 to a thickness of 0.1 μm. Further, on the titanium (Ti) film 24, α-Fe20
3. A magnetic thin film 25 is deposited to a predetermined thickness. Next, the above α-
The Fe203 thin film 25 is reduced and oxidized at a temperature of about 300 DEG C. to form a magnetic recording medium having a magnetic thin film 25a transformed into .gamma.-Fe203 as shown in FIG. During this reduction/oxidation treatment, the titanium dioxide (Ti
Oxygen in the film 23 is taken away by the Ti film 24, and the titanium dioxide (TiO2) film 23 becomes the first titanium sesquioxide (Ti203) film 23a, and the titanium film (Tf
) film 24 is a second titanium sesquioxide (Ti20a) film 24a with an intermediate film 22 formed thereon, thereby obtaining the magnetic recording medium targeted by the present invention.

Incidentally, (11 anodized ΔQ nonmagnetic substrate (
A γ-Fe203 magnetic film is directly provided on the alumite substrate (hereinafter referred to as an alumite substrate), and a lubricant (Krytox) is applied to the surface of the γ-Fe203 magnetic film.
．． Conventional magnetic recording medium spin-coded with 01 diluent,
(2) A first film with a thickness of 0.02 μm is placed on the alumite substrate.
γ-Fe20 with an intermediate film consisting of a titanium sesquioxide film and a second titanium sesquioxide film with a film thickness of
3 A magnetic film is provided and a lubricant (Krytox) is applied to the surface.
(3) A first titanium sesquioxide film with a thickness of 0.02 μm and a second titanium sesquioxide film with a thickness of 0.1 μm on an alumite substrate. In the present invention, a γ-Fe203 magnetic film is provided with an interlayer film in which two titanium sesquioxide films are alternately laminated, and a 0.01 dilution of a lubricant (Krytosox) is spin-coded on the surface of the γ-Fe203 magnetic film. For magnetic recording medium B etc., 20g
As a result of comparing the durability using a C3S test using a magnetic head loaded with a load of
Although peeling damage occurred in the Fe203 magnetic film, (2) magnetic recording medium A and (3) magnetic recording medium B according to the present invention
γ-F for 20,000 C3S tests
No peeling damage was observed in the e203 magnetic film, but it showed excellent durability.

(g) Effects of the Invention As is clear from the above explanation, according to the structure of the magnetic recording medium according to the present invention, the magnetic recording medium between the magnetically retentive substrate made of an alumite-treated aluminum substrate, etc. and the γ-Fe203 magnetic film. By interposing an intermediate film made of titanium sesquioxide film, the adhesion between the nonmagnetic substrate and the γ-Fe203 magnetic film is significantly improved. Therefore, peeling and damage to the magnetic film due to hendokranosh etc. can be prevented, and a highly durable and reliable magnetic recording medium can be provided.
It is extremely advantageous to apply this method to a magnetic disk device that employs this method.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part showing an embodiment of a magnetic recording medium according to the present invention, and FIGS. 2 and 3 are essential parts explaining an embodiment of a method for manufacturing a magnetic recording medium according to the present invention in the order of steps. FIG.

Claims (1)

[Scope of Claims] (Li) A magnetic recording medium in which a γ-Fe20 g magnetic thin film is provided on a non-magnetic substrate, wherein the non-magnetic substrate and a γ-Fe2
03 A first titanium sesquioxide film and a second titanium sesquioxide film are placed between the magnetic thin film.
What is claimed is: 1. A magnetic recording medium comprising an intermediate film in which at least one titanium sesquioxide film and at least one titanium sesquioxide film are alternately laminated. (2) The thickness of the first titanium sesquioxide film is 0.02
~0.1 μm, the thickness of the second titanium sesquioxide film is 0.0
The magnetic recording medium according to claim 1, wherein the magnetic recording medium has a thickness of 5 to 0.2 μm.