JPH0833990B2 - Method for forming lubricating layer of magnetic recording medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] A method of forming a lubricating layer on a surface of a recording medium such as a magnetic disk, which comprises: By rotating and sliding the head on the coated surface, a uniform lubricating layer can be obtained.

[Industrial use range]

The present invention relates to a method for forming a lubricating layer formed on a surface of, for example, a magnetic disk, and more particularly to a method for forming a lubricating layer which can make a lubricating layer made of a solid lubricant uniform and have a long life.

2. Description of the Related Art Recently, various magnetic devices have been developed and put into practical use as peripheral terminals of computers and their auxiliary devices. In the magnetic device, a magnetic disk, a magnetic drum, or the like is used as a magnetic recording medium, and writing / reading of data is performed by a magnetic head.

In such a magnetic recording medium, a lubricating layer is formed in order to improve durability when the magnetic head comes into contact, but a method for forming a lubricating layer having a uniform friction coefficient is desired in order to prolong the life of the magnetic recording medium. It is rare.

[Conventional technology]

Recording media, such as magnetic disks, are required to have larger capacities, and in order to meet this demand, the flying height of the magnetic head during operation tends to be reduced.

However, as the flying height of the magnetic head decreases, the contact failure between the magnetic head and the magnetic disk damages the magnetic recording layer of the magnetic disk. Head Crash
Since the possibility of occurrence of the above phenomenon increases, a method of providing a lubricating layer on the surface of the magnetic disk to reduce the frictional resistance at the time of contact has been attempted as one means for dealing with this. For example, a perfluoroalkylpolyether-based liquid, or an ester-based or higher fatty acid (having 12 to 14 or more carbon atoms) solid or semi-solid solid lubricant at room temperature is diluted with a solvent, and the magnetic fluid is added to the liquid lubricant tank. Immersion method of dipping the disk and applying it to the entire surface Spray method of spraying lubricant onto the recording surface of the rotating magnetic disk in a mist form The lubrication layer is formed by coating by a coating method or the like.

As described above, there are liquid lubricants at room temperature and solid or semi-solid lubricants as described above. However, liquid lubricants at normal temperature are adsorbed when the magnetic head and magnetic disk are left in contact with each other. From the viewpoint of adsorption, it is preferable to use a solid lubricant that does not cause adsorption.

[Problems to be solved by the invention]

According to the above-mentioned conventional method, when a solid lubricant is used, it becomes a solid state after the solvent is volatilized, but the lubricant layer deposited on the disk surface during the solidification process does not always have uniformity. Not not. That is, the lubricant becomes islands during the solidification process, and there are portions with and without the lubricant. For example, as shown in the measured values of three samples in FIG. Coefficient becomes non-uniform. Therefore, in the contact between the magnetic head and the magnetic disk during operation, when the magnetic head passes through a portion having a large friction coefficient, a failure such as a head crash occurs, resulting in destruction of recorded data or error in writing / reading data. There is a problem that the life of the magnetic disk may be shortened.

[Means for solving problems]

 FIG. 1 is a block diagram of the principle of the present invention.

In the figure, 1 is a magnetic recording medium, 2 is a recording surface, 3 is a solid lubricant applied to the recording surface 2, and 4 is a pressing head for pressing the recording surface 2 through the solid lubricant 3 with a predetermined pressure.

In the present invention, after applying the solid lubricant to the recording surface 3, the pressing head 4 is slid on the application surface while rotating the magnetic recording medium 1.

[Action]

The solid lubricant 3 is applied to the recording surface 2 of the magnetic recording medium 1,
By pressing the pressing head 4 from above the applied solid lubricant 3 with a predetermined pressure and sliding the pressing head 4 on the application surface while rotating the magnetic recording medium 1, the solid lubricant 3 is leveled. It is possible to form the lubricating layer uniformly, prevent occurrence of obstacles, and extend the life of the magnetic disk.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. The same reference numerals denote the same objects throughout the drawings.

In the side half sectional view of FIG. 2 (a), the magnetic disk 1a
The magnetic recording layer 1c is formed on the surface of the substrate 1b made of, for example, an aluminum disc.

The solid lubricant 3a is, for example, a solid lubricant of ester or higher fatty acid (having 12 to 14 or more carbon atoms) that is solid or semi-solid at room temperature, and is applied by dissolving it in a halogen-based organic solvent, for example. After a short time (for example, within 1 minute), the solid lubricant 3a is solidified and solidifies.

After applying the solid lubricant 3a, the pressing head 4a is urged by the pressing spring 4b, and the recording surface 2a of the magnetic disk 1a at a predetermined pressure P.
Is pressed through the solid lubricant 3a. Further, it can be moved in the directions of arrows A and B over all the tracks on the recording surface 2a in the pressed state.

The spindle 5 is connected to the motor M, and the magnetic disk 1a attached to the upper end of the spindle 5 rotates at a predetermined rotation speed N when the motor M is driven.

Here, the predetermined pressure P and the predetermined rotation speed N are the pressing force and the rotation speed for uniformly forming the lubricating layer with a desired thickness,
The third shows the optimum range of the experimental results by hatching in the figure, for example, the pressing force P is set to ^{1g / mm 2 ~50g / mm 2} , also the rotational speed N is set to 1000rpm or less.

Therefore, the method of forming the lubricating layer will be described with reference to the flowchart of FIG. 4. First, the magnetic disk 1a is attached to the upper end of the spindle 5.

A solid lubricant 3a dissolved in a solvent is applied on the recording surface 2a of the magnetic disk 1a.

The pressing head 4a is set on the recording surface 2a where the solid lubricant 3a is slightly solidified. (See FIG. 2 (b)) The motor M is driven to rotate the magnetic disk 1a at a predetermined rotation speed N.

The pressing head 4a is moved in the directions of arrows A and B over the entire track to even out the lubricating layer. (See FIG. 2 (c)) In this way, the lubricating layer was uniformly formed to a desired thickness, and as shown in FIG. 5 showing the measurement results of three samples according to the example, the maximum friction coefficient was It becomes as low as the minimum friction coefficient of the conventional example, and the friction coefficient can be made extremely uniform,
Further, since the adhesion of the lubricant is increased and the durability is also improved, it is possible to prevent troubles such as head crush due to contact between the magnetic head and the magnetic disk, and it is possible to extend the life of the magnetic disk.

〔The invention's effect〕

As described above, according to the present invention, since the lubricating layer can be formed uniformly and the adhesion between the disk surface and the lubricant can be improved, obstacles such as head crash can be prevented and the life of the magnetic recording medium can be prevented. There is an effect that can be extended.

[Brief description of drawings]

FIG. 1 is a block diagram of the principle of the present invention, FIG. 2 is a side sectional view showing an embodiment of the present invention, FIG. 3 is an explanatory view of the embodiment, FIG. 4 is a flowchart of the embodiment, and FIG. FIG. 6 is a graph showing the friction coefficient of the lubricating surface of the example, and FIG. 6 is a graph showing the friction coefficient of the lubricating surface of the conventional example. In the figure, 1 is a magnetic recording medium, 1a is a magnetic disk, 2 and 2a are recording surfaces,
3, 3a are solid lubricants, 4, 4a are pressing heads, and 4b are pressing springs.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Terada 162 Shirahane, Shirahoji, Tokai-mura, Naka-gun, Ibaraki Prefecture Nippon Telegraph and Telephone Corporation Ibaraki Telecommunications Research Institute (72) Inventor Yumu Sato Musashino City, Tokyo 3-9-11 Midoricho, Nippon Telegraph and Telephone Corporation, Research Institute for Electronic Mechanism (56) References Japanese Patent Laid-Open No. 59-1163 (JP, A)

Claims (1)

[Claims] 1. A method of applying a lubricant to a recording surface (2) of a magnetic recording medium (1) to form a lubricating layer, wherein a solid lubricant (3) is applied to the recording surface (2). After that, the pressing head (4) is pressed against the recording surface (2) through the solid lubricant (3) with a predetermined pressure, and the magnetic recording medium (1) is rotated to record the pressing head (4). A method for forming a lubricating layer of a magnetic recording medium, which comprises sliding on a surface (2).