JPH04366418A - Magnetic recording device and its manufacture - Google Patents

Abstract

PURPOSE:To enable a rolling friction to be generated and friction due to contact or sliding to be reduced for improved wear resistance by providing a protruding portion on a contact surface by using a uniform, spherical, and hard particulates and then forming a uniform surface roughness. CONSTITUTION:A magnetic recording device has a rolling surface on a magnetic layer 3 which is located on an aluminum substrate 4 and the rolling surface is constituted by allowing a particulates 1 to be buried into a protection layer 2 on the magnetic layer 3. Then, since there is a slight space between a hole and the particulates 1, the particulates 1 can freely rotate within a hole. Also, a film thickness of the protection film 2 is smaller than a grain diameter of the particulates 1 and one portion of the particulates 1 protrudes from a surface but does not deviate from the protection film 2. Then, when a protruding portion of the particulates 1 contacts a magnetic head slider, the particulates 1 rotates and friction becomes small. Further, when this rolling surface is covered with a lubricant 5, the particulates can rotate easily, a low friction can be achieved, and a friction resistance can be improved.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a magnetic recording device and its magnetic recording device which require wear resistance necessary for continuous sliding or to reduce the size of a magnetic recording medium and a magnetic head slider for the purpose of increasing recording capacity. Regarding the manufacturing method.

0002

[Background Art] With the recent increase in the density of magnetic recording devices,
The distance between the magnetic recording medium and the magnetic head slider (generally referred to as the flying height) tends to become smaller.

On the other hand, as the flying height continues to become narrower, the magnetic head slider comes into contact with the surface roughness (protrusions, etc.) of the magnetic recording medium, destroying the magnetic layer or sometimes damaging the slider itself, which is called a head crash. The probability of occurrence increases. In order to avoid this, efforts have been made to reduce the surface roughness of the magnetic recording medium and the magnetic head slider to improve their smoothness.

Most recent magnetic recording devices are of the CSS (contact start/stop) type, in which the slider is in contact with the magnetic recording medium when the device is at rest. For this reason, if the smoothness is improved, a problem arises in that when the magnetic recording medium and the magnetic head slider come into contact, they are attracted to each other. When this attraction occurs, if the attraction force is stronger than the rotational force, the magnetic recording medium may not be able to rotate, or if it is forcibly rotated, the magnetic head slider may not be able to fly, or the magnetic recording medium or magnetic head slider may not be able to fly. may be damaged. In order to avoid these problems, uniform irregularities of a certain size are formed on the surface.

For example, as described in Japanese Patent Laid-Open No. 1-273219, a hard carbon protective film is formed on an island using a vapor phase growth method to form irregularities, and as described in Japanese Patent Application Laid-Open No. 1-319121, There is a method of dispersing fine particles under the layer to make the surface roughness of the magnetic recording medium uniform.

[0006]

However, the prior art is based on the premise of floating, and aims to make head slashing and adhesion between the magnetic recording medium and the magnetic head slider less likely to occur. However, in response to the increasing density of magnetic recording media year by year, the flying height tends to become smaller than ever. Therefore, during CSS, that is, when the magnetic head slider flies or lands, the sliding distance increases significantly. Furthermore, considering that during this sliding, the magnetic recording medium and the magnetic head slider work through sliding friction, wear becomes more of a problem than before. Furthermore, in the near future, it will be necessary to realize a contact recording method in which the magnetic recording medium and the magnetic head slider are brought into active contact. As the flying height becomes smaller in this way, a solution to the attraction and wear between the magnetic recording medium and the magnetic head slider becomes an urgent issue. However, conventional techniques cannot address these problems.

The object of the present invention is not only to solve the above-mentioned problems, but also to
The purpose is to solve the problems of friction and wear caused by contact or sliding, and to make contact recording possible.

[0008]

[Means for Solving the Problem] The above object is achieved by a magnetic recording device in which freely rotating spherical fine particles form a rolling surface on either the surface of the magnetic recording medium or the magnetic head slider. Ru.

[0009]

[Operation] In the present invention, uniform, spherical, and hard fine particles are used to provide convex portions on the contact surface to form a uniform surface roughness. This solves the adsorption problem. In addition, in contact during levitation, sliding during CSS, and future contact recording, conventional technology uses sliding friction, but in the present invention, these fine particles form a rolling mechanism, resulting in rolling friction, and the friction coefficient In addition to being small, wear resistance is also improved.

0010

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 to 10.

Embodiment 1 of the present invention is shown in FIG. FIG. 1 is a schematic cross-sectional view of a magnetic recording medium having a rolling surface on a magnetic layer 3 on an aluminum substrate 4. As shown in FIG. The rolling surface is composed of fine particles 1 embedded in a protective film 2 on a magnetic layer 3. A spherical hole is provided in the protective film 2, and the fine particles 1 are placed inside it, and there is a small space between the hole and the fine particle 1.
The microparticles 1 can freely rotate within the holes. It is assumed that the thickness of the protective film 2 is smaller than the particle size of the fine particles 1. Further, it is assumed that a part of the fine particles 1 protrudes from the surface. However, it is assumed that the fine particles 1 do not come off the protective film 2. When the protruding portion of the particle 1 comes into contact with the magnetic head slider, the particle 1 rotates and the friction is reduced. Furthermore, by covering the rolling surface with the lubricant 5, the fine particles 1 rotate more easily, and low friction and improved wear resistance are promoted. As a result, even if the magnetic head slider and the magnetic recording medium come into contact with each other, contact damage will not occur between the two. Therefore, a magnetic recording device capable of recording and reproducing without malfunction can be provided.

Example 2 is shown in FIG. FIG. 2 is a schematic cross-sectional view of a magnetic recording medium having a rolling surface in the magnetic layer 3. As shown in FIG. In the case of Example 2, the fine particles 1 are embedded in the magnetic layer 3 and form a rolling surface, so the magnetic layer 3 itself also plays the role of a protective film. This eliminates the need for a protective film, leading to a shorter production process for magnetic recording media and further to lower costs. Further, as in Example 1, low friction and improved wear resistance are achieved, and the reliability of the device is improved. In this case, the total cross-sectional area of the particles 1 within the minimum recording area (1 bit) must be smaller than 1 bit so as not to interfere with electromagnetic conversion.

Example 3 is shown in FIG. FIG. 3 is a schematic cross-sectional view of a magnetic recording medium in which the rolling surface is constructed with both a magnetic layer 3 and a protective film 2 interposed therebetween. This method is characterized in that it is not affected by the size of the fine particles 1. The fine particles 1 are embedded in the magnetic layer 3 to the extent that they do not interfere with electromagnetic conversion, and the missing part is compensated for by the protective film 2.

Furthermore, in Examples 1 to 3, by providing the lubricant 5 only around the particles 1 in the holes as shown in FIG. 4, the particles 1 can be easily rotated.
However, the attraction between the lubricant 5 on the magnetic recording medium and the magnetic head slider can be eliminated.

Example 4 is shown in FIG. FIG. 5 is a schematic cross-sectional view of a magnetic head slider having a rolling surface. In the case of current floating type magnetic recording devices, the slider has a floating rail 10 as shown in FIG.
Form a rolling surface on the surface. This prevents adsorption during starting and stopping. Furthermore, the same effects as in Example 1 can be expected.

Example 5 is shown in FIG. FIG. 7 shows a structure in which a mechanism for supplying lubricant 5 to the magnetic head slider of FIG. 5 is provided. A porous layer 8 is provided on the rolling surface, and the lubricant 5 is supplied from above. Note that the lubricant 5 is in the lubricant tank 11.
Supplied from. As a result, a constant amount of lubricant 5 is always supplied to the contact surface between the magnetic recording medium and the magnetic head slider through the rolling surface.

Example 6 is shown in FIG. FIG. 8 is a schematic cross-sectional view of a magnetic head slider when performing contact recording. For contact recording, the slider does not need to have a rail like the conventional one. Since it has a rolling surface, it can also handle seek operations, and it is made into a partial sphere so that the load is evenly applied. Moreover, by holding the head 7 at the center of the partial sphere, accurate positioning can be achieved. Further, the supply of lubricant 5 is also achieved using the same mechanism as in the fifth embodiment.

Furthermore, in the fifth and sixth embodiments described above, the entire slider 6 may be made of porous material to further facilitate the supply of lubricant.

The magnetic recording device of the present invention has a rolling surface formed on the surface of the magnetic recording medium, the magnetic head slider, or both.

The fine particles forming the rolling surface are uniform, spherical, and hard. For example, carbide (WMoC
, SiC, TiC, WC), nitrides (ZrNbN, Cr
TaN, AlN, Si3N4), oxides (Ta2O5,
Al2O3, ZrO2), boride, and diamond are used. Alternatively, fine particles of metal may be used.

Example 7 is shown in FIG. FIG. 9 shows a method of forming rolling surfaces.

First, the fine particles are coated with a solvent-soluble plastic having a low degree of crosslinking, such as polyethylene, polystyrene, polyvinyl chloride, or acrylic resin. Alternatively, ultrafine particles of these plastics are attached around the fine particles. The thickness of the plastic film adhering to the surface is 1/10 or less of the diameter of the core particles.

Next, a mixed solution of the surface-treated fine particles and a binder is prepared and applied by dipping or spin coating. It is assumed that the fine particles are uniformly dispersed in the solution. After that, heat treatment completes the crosslinking of the binder and strengthens it. An example of such a binder is a solution of ethyl arsenate and transition metal nitrate in alcohol and water. Incidentally, the embedding rate of the fine particles can be controlled by the viscosity of the binder (which changes depending on the temperature) and the pulling rate of dipping.

Finally, toluene and dimethylformamide (
When the plastic around the fine particles is eluted in a solvent such as DMF) or tetrahydrofuran (THF), a gap is created between the fine particles and the binder, forming a rolling surface. At this time, elution can be promoted by heating.

Furthermore, instead of plastic, the surfaces of the fine particles are coated with ultrafine particles of a solid lubricant, such as molybdenum disulfide. There is also a method of applying these fine particles in the same way.

Example 8 is shown in FIG. FIG. 10 also shows a method of forming rolling surfaces. This rolling surface forming method utilizes the difference in coefficient of thermal expansion between the fine particles and the binder. The fine particles used are made of a material with a larger coefficient of linear expansion than the binder.

First, a mixed solution of fine particles and a binder is prepared and applied at high temperature. The coating method is the same as in Example 7.

When cooled, the fine particles contract due to the difference in coefficient of thermal expansion, creating gaps between the fine particles and the binder to form rolling surfaces.

[0029]

According to the present invention, it is possible to reduce the coefficient of friction between the magnetic recording medium and the magnetic head slider, as well as the wear, so that magnetic recording with excellent wear resistance can be achieved even in the case of low-flying sliders and contact recording. equipment can be provided.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a magnetic recording medium of Example 1.

FIG. 2 is a cross-sectional view of a magnetic recording medium of Example 2.

FIG. 3 is a cross-sectional view of a magnetic recording medium of Example 3.

FIG. 4 is a cross-sectional view of a magnetic recording medium.

FIG. 5 is a longitudinal cross-sectional view of a magnetic head slider according to a fourth embodiment.

FIG. 6 is a cross-sectional view of the magnetic head slider of Example 4.

FIG. 7 is a cross-sectional view of a magnetic head slider of Example 5.

FIG. 8 is a cross-sectional view and a plan view of a magnetic head slider of Example 6.

FIG. 9 is a diagram showing a method for forming a rolling surface in Example 7.

FIG. 10 is a diagram showing a method for forming a rolling surface in Example 8.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1... Fine particles, 2... Protective film, 3... Magnetic layer, 4... Aluminum substrate, 5... Lubricant, 6... Slider, 7... Head, 8...
porous, 9... lubricant supply port, 10... levitation rail, 11
…Lubricant tank.

Claims (9)

[Claims] 1. A magnetic recording device comprising a rotating disc-shaped magnetic recording medium, a magnetic head for recording and reproducing information on the magnetic recording medium, and a slider mounted with the magnetic head, wherein a surface of the magnetic recording medium, Alternatively, a partially open spherical hole is provided in the surface of the magnetic head slider facing the magnetic recording medium, and substantially spherical fine particles having a diameter smaller than the diameter of the spherical hole are placed in the hole so that a portion of the fine particles extends from the surface. A magnetic recording device characterized in that it is formed in a protruding manner, and the protruding surface forms a rolling surface. 2. The magnetic recording device according to claim 1, wherein the diameter of the opening of the hole is smaller than the particle size of the fine particles. 3. The magnetic recording device according to claim 1, wherein a lubricant is provided around the fine particles and the holes for holding the fine particles. 4. The magnetic recording medium or the magnetic head slider is provided with a lubricant supply means for supplying lubricant to the particulates and the holes for holding the particulates. 1. The magnetic recording device according to 1. 5. A thin film magnetic recording medium (sputter disk) comprising an aluminum substrate, an underlayer such as Cr or Ni-P, a magnetic layer made of Co, Cr, Ta, etc., and a protective layer provided on the magnetic layer. Claim 1 characterized in that the protective film is provided with holes for holding the fine particles and the fine particles.
5. The magnetic recording device according to claim 4. 6. Magnetism of a thin film magnetic recording medium (sputter disk) consisting of an aluminum substrate, an underlayer such as Cr or Ni-P, a magnetic layer made of Co, Cr, Ta, etc., and a protective layer provided on the magnetic layer. 5. The magnetic recording device according to claim 1, further comprising holes for holding the fine particles and the fine particles in the layer or in both the magnetic layer and the protective layer. Claim 7: An aluminum substrate and an aluminum substrate coated on the aluminum substrate.
2. A magnetic recording medium (coated disk) comprising a magnetic layer made of iron oxide, resin, and alumina, wherein holes for holding the fine particles and fine particles are provided in the magnetic layer. The magnetic recording device according to claim 4. 8. The rolling surface is formed by coating the surface of the fine particles with plastic, applying the fine particles together with a binder, and then eluting the plastic with a solvent. A method of manufacturing the magnetic recording device described above. 9. Manufacturing a magnetic recording device according to claim 1, wherein the fine particles are coated together with a binder at a high temperature, and then cooled to form a rolling surface due to a difference in coefficient of thermal expansion. Method.