JPS58222445A - Orienting method - Google Patents

Abstract

PURPOSE:To improve the degree of orientation and the reduce the orienting time, by installing numerous gaps to an orienting magnet. CONSTITUTION:Orienting magnets 9 are arranged at the top and bottom in plural pieces respectively, with a magnetic disk base plate 8 in between, and gaps 9a are installed between each magnet 9, and thus, magnetic fields of the same direction are formed. In the first place, the orienting magnets 9 are saved upward and downward, and the magnetic disk base plate 8 is spin-coated with a magnetic medium paint while the base plate 8 is rotated at a high speed. Then, the orienting magnets 9 are brought nearer to the magnetic disk base plate 8. At this time, the orienting magnets 9 are rotated at a speed slower than that of the base plate 8. The rotations of the base plate 8 and magnets 9 are continued until the paint is dried, and thus, the magnetic power of the paint is oriented.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a magnetic coating film applied to a magnetic disk, and particularly to a method for orienting magnetic powder contained in the magnetic coating film.

(2) Background of the Technology Magnetic disk drives have been used as storage devices for electronic computing devices and the like. The magnetic disk used as the storage medium is made of a substrate made of super-finished aluminum or the like and coated with paint containing magnetic powder by a spin code method. γ-Fe2O3 is often used as the magnetic powder. γ-Fe20° is produced by dehydrating and reducing acicular α-F@OOH in a hydrogen stream to obtain Fe,04, which is then oxidized at low temperature in air. When this magnetic powder is applied, the noise characteristics vary depending on the size of the crystal particles and the application process, and in order to improve the reproduction output, the magnetic powder is passed through a DC magnetic field to align the axis of easy magnetization before drying.

(3) Prior art and problems Figure 1 is a diagram for explaining the conventional orientation method for aligning the directions of easy magnetization axes of magnetic powder, in which a is a top view, b is a side view, and C is a front view. are shown respectively. In the figure, reference numeral 1 denotes a magnetic disk substrate, which is attached to a shaft 2 so that it can rotate at high speed.

3 to 6 are magnets, which are provided to sandwich the magnetic disk substrate, and have gaps f7. They are arranged so that a magnetic field as shown in Figure 0 is generated at γ. After spin-coding the paint containing magnetic powder while rotating the magnetic disk substrate 1 at high speed,
The magnetic powder is oriented by the magnets 3 to 6 at a low rotation speed until the paint dries. In this case, it is necessary to rotate the magnetic disk substrate at a low speed in order to sufficiently orient the magnetic powder.

However, in recent magnetic disks, the ability to make the magnetic coating film thinner is required to increase the recording density! requested. For this reason, there is a need to develop an orientation method that can process the magnetic paint by high-speed rotation after the spin code.

(4) Purpose of the Invention Based on the above-mentioned conventional requirements, the present invention aims to provide an orientation method capable of orienting magnetic powder coated on a magnetic disk at high speed rotation.

(5) Structure and object of the invention According to the present invention, there is provided a method for orienting a magnetic medium during coating and drying of a magnetic medium coating film on a magnetic disk, the method comprising: an orienting gear having one or more orienting magnets;
This is achieved by providing an orientation method characterized in that the orientation magnet is rotated in the rotation direction of the magnetic disk substrate and the relative speed with the magnetic disk substrate is reduced to orient the magnetic medium. .

(6) Examples of the invention Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a diagram for explaining the orientation method according to the present invention, in which a shows a side view of an apparatus capable of carrying out the method of the present invention, and b shows a view taken along the arrow 2 in FIG. In the figure, 8 is a magnetic disk substrate, 9 is a permanent magnet for orientation, and 10 is a magnetic disk substrate.
1 is a shaft for supporting and rotating the magnetic disk substrate;
1 is a motor for driving the magnetic disk substrate and the orientation magnet, 12 is a counter shaft for transmitting rotation to the orientation magnet, 13 is a shaft for the orientation magnet, 14.15 is a fixed bearing box, and 16 is a A rotatable bearing box for the orientation magnet that can slide on one shaft 10, 17-24 are pulleys, 25-2
8 indicates a belt.

The magnetic disk substrate 8 is supported by a shaft 10, and the sea IJ18
, a belt 25, and a pulley 17 to rotate the motor 11. The counter shaft 12 is made of Goo 920% belt 26. Rotation is applied by the shaft 10 via the sea 1J19. A plurality of orientation magnets 9 are arranged above and below the magnetic disk substrate 8, and a gap 9a is provided between each magnet to form a magnetic field in the same direction as shown in Figure b.

The upper orientation magnet 9 is attached to the shaft 13, is rotated by the counter shaft 12 via the pulley 23, belt 28, and pulley 22, and can be retracted upward as shown by the two-dot chain line. It is now possible to do so. The lower orientation magnet 9 is attached to the bearing box 16, and the pulley 24 and belt 2
7. It is rotatably driven by the counter shaft 12 via the pulley 21, and can be retracted downward on the shaft 10 as shown by the two-dot chain line. Note that the orientation magnet 9
The rotation direction of the magnetic disk substrate 8 is the same as that of the magnetic disk substrate 8, and the magnetic disk substrate 8 is rotated at a slightly slower speed.

In the orientation method of the present invention using the apparatus configured as described above, first, the orientation magnet 9 is retracted vertically, and the magnetic media paint is spin-coded while the magnetic disk substrate 8 is rotated at high speed. Next, the magnetic disk substrate continues to rotate at high speed, and the orientation magnets 9 are brought close to its upper and lower surfaces. Of course, at this time, the orientation magnet 9 is being rotated by the counter shaft 12 at a slightly slower speed than the magnetic disk substrate 8.
Its relative velocity is small. This rotation continues until the magnetic medium paint dries to orient the magnetic powder, which is the magnetic medium.

In the orientation method of the present invention performed as described above, by providing a large number of gaps in the orientation magnet 9, it is possible to improve the degree of orientation and shorten the orientation time. Furthermore, since the process can be performed at a high rotational speed, it becomes easy to thin the coating film. Furthermore, by filling the gear and nook parts with non-magnetic material to make the orientation magnet similar to a single disc, there are no edge parts and wind generation can be prevented, improving the accuracy of the coating surface and the film thickness. Uniformity is also possible.

(7) Effects of the Invention As explained in detail above, the orientation method of the present invention rotates the orientation magnet together with the magnetic disk substrate.
This has great effects such as improving the degree of orientation, shortening the orientation time, making the coating film thinner and more uniform, and improving the precision of the coating surface.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining a conventional orientation method, and FIG. 2 is a diagram for explaining an orientation method according to the present invention. In the drawings, 8 is a magnetic disk substrate, 9 is an orientation magnet, 10 is a shaft, 11 is a drive motor, and 12d is a counter shaft. Patent applicant Fujitsu Ltd. Patent application agent Akira Aoki Patent attorney Kazuyuki Nishidate Patent attorney Yukio Uchida Akira Yamaguchi Figure 1

Claims (1)

[Claims] 1. A method for orienting a magnetic medium during coating and drying of a magnetic medium coating film on a magnetic disk, wherein the orienting magnet has one or more orienting gaps, and the orienting magnet is rotated in the direction of rotation of the magnetic disk substrate. An orientation method characterized by orienting a magnetic medium by rotating the magnetic medium at a low relative speed to a magnetic disk substrate.