JP4128859B2 - Magnetic recording medium, method for manufacturing the same, and magnetic recording apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a magnetic recording medium , a method of manufacturing the same, and a magnetic recording apparatus, and in particular, a lubricant for preventing occurrence of damage during loading in a magnetic recording apparatus employing a ramp loading / unloading mechanism of a magnetic head. The present invention relates to a magnetic recording medium having a characteristic structure, a manufacturing method thereof, and a magnetic recording apparatus.
[0002]
[Prior art]
The mechanism for retracting / returning the magnetic head for recording / reproducing information from the information recording medium, that is, the magnetic head loading / unloading mechanism improves the shock resistance during non-operation, does not cause magnetic head adsorption, etc. In this respect, it is advantageous to a CSS (contact start / stop) type apparatus in which a magnetic head is always present on an information recording medium.
[0003]
Such a magnetic head loading / unloading mechanism has been known for a long time. However, in recent years, with the demand for improvement in recording density and impact resistance of magnetic recording devices, the magnetic head has been reduced in flying height. For the purpose of improving the impact resistance, it is particularly adopted in HDD devices and the like mounted on portable notebook personal computers.
[0004]
Here, the ramp load / unload mechanism will be described with reference to FIG.
FIG. 7 is an explanatory diagram of the loading operation of the magnetic head by the ramp loading / unloading mechanism. The ramp 61 is a locus in the radial direction of the magnetic head 65 that is moved by a rotary actuator (not shown) of the HDD device. It is provided on the outer side, and is composed of an inclined path 62, a horizontal path 63, and a stop portion 64 that stops and holds the magnetic head 65.
[0005]
The magnetic head 65 stops at a position pressed against the outer side of the stop portion 64 in the stop state. However, when receiving a command from the host and positioning the magnetic disk 71, the magnetic head 65 is moved from the stop portion 64 to the magnetic disk. The movement starts to the side 71, and loads from the horizontal path 63 through the inclined path 62 to the landing area 72 provided in the peripheral portion of the magnetic disk 71.
[0006]
At this time, the moving speed of the magnetic head 65 is moved at a slow speed of 1/10 or less, which is sufficiently slower than the seek speed on the magnetic disk 71, so that the landing area 72 is smooth without colliding with the disk surface during loading. The magnetic head 65 is controlled so as to be positioned in a floating state.
[0007]
Next, the configuration of a conventional magnetic disk will be described with reference to FIG.
In the figure, only one main surface side of the glass substrate is shown, but the actual one is formed symmetrically on both main surface sides.
Refer to FIG. 8. First, a CrMo underlayer 75 having a thickness of, for example, 3 nm and a thickness of, for example, 20 nm on both surfaces of a 2.5-inch (≈6.5 cm) glass substrate 73 with a NiP layer 74 interposed therebetween. The CoCrPt magnetic recording layers 76 are sequentially stacked.
[0008]
Next, a DLC (diamond-like carbon) protective film 77 having a thickness of about 10 nm is provided on the CoCrPt magnetic recording layer 76 by various methods such as a PVD method and a CVD method, and the entire surface thereof is a lubricant having a thickness of about 1 to 2 nm. By covering with 78, durability and corrosion resistance are improved.
[0009]
In addition, as the lubricant 78 applied on the DLC protective film 77, a perfluoropolyether lubricant, which is a fluorine-based lubricant having various polar groups at its ends, is used, a dipping method, a spin coat method, or a spray. It is applied and adhered onto the DLC protective film 77 by a method or the like.
[0010]
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-338478
[Problems to be solved by the invention]
However, the ramp load / unload mechanism described above also has a problem that damage occurs on the medium when the magnetic head is loaded / unloaded.
[0012]
Therefore, an object of the present invention is to solve the occurrence of damage on the magnetic recording medium when the magnetic head is loaded / unloaded on the magnetic recording medium side.
[0013]
[Means for Solving the Problems]
FIG. 1 is an explanatory diagram of the principle configuration of the present invention. Means for solving the problems in the present invention will be described with reference to FIG.
Referring to FIG. 1, in order to achieve the above-described object, the present invention provides a boundary between an inner peripheral portion 2 and an outer peripheral portion 3 in a magnetic recording medium 1 including an inner peripheral portion 2 that performs recording and an outer peripheral portion 3 that loads a magnetic head. Are provided with relief grooves for the lubricants 4 and 5, and the lubricant 5 covering the outer peripheral portion 3 is superior in impact resistance to the lubricant 4 covering the inner peripheral portion 2 .
[0014]
As described above, the lubricant 5 covering the outer peripheral portion 3 of the magnetic recording medium 1 is made to have a higher impact resistance than the lubricant 4 covering the inner peripheral portion 2, so that the outer periphery for loading the magnetic head is used. The impact resistance of only the portion 3 can be improved, and the inner peripheral portion 2 can use the lubricant 4 suitable for the flying characteristics of the slider.
Further, since the relief grooves 6 for the lubricants 4 and 5 are provided at the boundary between the outer peripheral portion 3 and the inner peripheral portion 2, the lubricant 5 that covers the outer peripheral portion 3 and the lubricant 4 that covers the inner peripheral portion 2 are provided. , 5 can be prevented.
[0015]
Further, it is desirable to make the thickness of the lubricant 5 covering the outer peripheral portion 3 larger than the thickness of the lubricant 4 covering the inner peripheral portion 2, so that the shock resistance at the outer peripheral portion 3 where the magnetic head is loaded. Can be further improved.
[0017]
As the lubricant 5 for covering the outer peripheral portion 3, it is desirable to use a lubricant containing a phosphorus-containing fluorine compound, for example, a fluorine compound having a phosphazene ring.
[0018]
In addition, as the lubricant 4 that covers the inner peripheral portion 2, it is desirable to use a synthetic oil containing fluorine, for example, PFPE (Perfluoroalkyl Polyether).
[0019]
Further, when the magnetic recording medium 1 having such a configuration is manufactured, the first lubricant 5 is applied to the outer peripheral portion 3 by either the dipping method or the spray coating method with the inner peripheral portion 2 covered with a mask. After the coating, the outer peripheral portion 3 is covered with a mask, and the second lubricant 4 having a lower impact resistance than the first lubricant 5 is applied to the inner peripheral portion 2 by either the dipping method or the spray coating method. What is necessary is just to coat.
The covering order may be reversed.
[0020]
Alternatively, relief grooves 6 for the lubricants 4 and 5 are provided at the boundary between the inner peripheral portion 2 and the outer peripheral portion 3, and the first lubricant 4 is dropped on the inner peripheral portion 2 and the first lubrication is applied to the outer peripheral portion 3. The second lubricant 5 having better impact resistance than the agent 4 may be dropped and applied by spin coating.
[0021]
By mounting the magnetic recording medium 1 having the above-described configuration, it is possible to realize a magnetic recording apparatus with excellent impact resistance, and it is particularly suitable as a magnetic recording apparatus mounted in a portable information processing apparatus.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Here, with reference to FIGS. 2 to 3, a method of manufacturing the magnetic disk according to the first embodiment of the present invention will be described.
2A. First, a lubricant relief groove 22 having a width of 0.8 mm and a depth of 1 μm, for example, is formed near the outermost periphery of both surfaces of a 2.5-inch (≈65 mm) glass substrate 21. Then, it is divided into an inner peripheral part 11 which becomes a data zone for recording and an outer peripheral part 12 for landing the magnetic head.
The center position of the escape groove 22 is 30 mm from the center of the glass substrate 21, and the landing position of the magnetic head is about 30.5 mm.
[0023]
Next, referring to FIG. 2B, a CrMo underlayer 24 having a thickness of, for example, 3 nm and a CoCrPt magnetic recording layer 25 having a thickness of, for example, 20 nm are sequentially formed on both surfaces of the glass substrate 21 via the NiP layer 23. After the lamination, a DLC protective film 26 of about 5 nm is provided.
[0024]
Next, referring to FIG. 3C, a lubricant 27 having the following structural formula (1), for example, perfluoropolyether as a fluorine-based lubricant, is dropped near the center of the inner peripheral portion 11 of the magnetic disk 10, and Lubricant 28 having improved impact resistance by adding 5 to 10%, for example, 10%, of a phosphorous-containing fluorine compound, for example, a fluorine compound having a phosphazene ring, to perfluoropolyether near the escape groove 22 of the outer peripheral portion 12. Apply spin while dropping.
[0025]
FIG. 3D is an enlarged view of the vicinity of the escape groove 22, and the lubricant 27 dropped on the inner peripheral portion 11 is pushed to the outer peripheral portion 2 side by centrifugal force caused by spin coating. However, the lubricant is accommodated in the escape groove 22, reaches the outer peripheral portion 12 beyond the escape groove 22, and is not mixed with the lubricant 28 dropped on the outer peripheral portion 12.
In this case, the thicknesses of the lubricants 27 and 28 are both 1 nm, for example.
[0026]
As described above, in the first embodiment of the present invention, the lubricant 28 having higher impact resistance than the lubricant 27 applied to the inner peripheral portion 11 is applied to the outer peripheral portion 12 on which the magnetic head is landing. Therefore, it is possible to effectively prevent the magnetic disk 10 from being damaged due to an impact when the magnetic head is loaded / unloaded.
[0027]
Further, since the relief groove 22 is provided between the inner peripheral portion 11 and the outer peripheral portion 12, lubricants having different characteristics are simultaneously applied to the inner peripheral portion 11 and the outer peripheral portion 12 in a single spin application process. And the coating process can be simplified.
[0033]
Next, with reference to FIG. 4 , a second embodiment relating to a magnetic disk device equipped with the magnetic disk of the first embodiment of the present invention will be described.
FIGS. 4 (a) see Figure 4 (a) is a schematic plan view of a second embodiment of a magnetic disk apparatus of the present invention, the magnetic disk 10 is mounted on a spindle motor 42 fixed to the housing 41 Therefore, the spindle motor 42 is rotated at a predetermined rotational speed.
A magnetic head 45 that reads and writes magnetic information recorded on the magnetic disk 10 is supported by a suspension 44 and floats by an airflow generated as the magnetic disk 10 rotates.
[0034]
The suspension 44 is held by a carriage 46 attached to the hub, and the carriage 46 is driven by an actuator 47 in a head retracting direction or a head returning direction indicated by an arrow in the drawing.
A lift tab 43 is attached to the tip of the suspension 44, and a ramp 48 for holding the lift tab 43 when the magnetic head 45 is retracted is provided.
[0035]
See FIG. 4 (b) FIG. 4 (b) is a schematic cross-sectional view taken along one-dot chain line connecting A-A 'in FIG. 4 (a), when retraction of the magnetic head 45, ramps 49 of the ramp 48 The lift tab 43 is slid using the cam curved surface formed of the horizontal path 50 as a guide, and is stopped at the parking position of the stop portion 51 provided outside the horizontal path 50.
[0036]
In FIG. 4 , the lift tab 43 at the tip of the magnetic head 45 is slid with the ramp 48, but even if a part of the suspension 44 on the rear end side of the magnetic head 45 is slid with the ramp 48, The retracting / returning operation of the head 45 is possible.
[0037]
As mentioned above, although each embodiment of the present invention has been described, the present invention is not limited to the configuration described in each embodiment, and various modifications can be made.
For example, in the description of the first embodiment, the thickness of the lubricant applied to the inner peripheral portion 11 and the thickness of the lubricant applied to the outer peripheral portion 12 are the same, but need not be the same. In order to further improve the impact resistance, the thickness of the lubricant 28 provided on the outer peripheral portion 12 may be made larger than the thickness of the lubricant 27 provided on the inner peripheral portion 11.
For example, when the thickness of the lubricant 27 provided on the inner peripheral portion 11 is 1 nm, the thickness of the lubricant 28 provided on the outer peripheral portion 12 is, for example, 2 nm.
[0038]
In the description of the first embodiment, PFPE is used as the lubricant to be applied to the inner peripheral portion 11, and lubrication is performed by adding a fluorine compound having a phosphazene ring to PFPE as the lubricant to be applied to the outer peripheral portion 12. Although the agent is used, it is not limited to such a combination.
[0039]
For example, as the lubricant provided in the inner peripheral portion 11, synthetic oil containing fluorine other than PFPE may be used.
[0040]
Further, as the lubricant provided on the outer peripheral portion 12, a fluorine compound containing phosphorus other than the fluorine compound having a phosphazene ring may be used.
[0041]
In the first embodiment, the lubricant 27 provided on the inner peripheral portion 11 and the lubricant 28 provided on the outer peripheral portion 12 are the same lubricant, but a combination of PFPE lubricants having different end groups is used. As long as the impact resistance of the lubricant 28 applied to at least the outer peripheral portion 12 is superior to that of the lubricant 27 provided on the inner peripheral portion 11, it is sufficient.
[0044]
The layer structure and material construction of the magnetic disk in the first embodiment described above is merely an example, it goes without saying that also apply to a magnetic disk having a layer structure and material construction of the various known.
[0045]
Here, referring again to FIG. 1, the detailed features of the present invention will be described.
1 (Appendix 1) In a magnetic recording medium 1 comprising an inner periphery 2 for recording and an outer periphery 3 for loading a magnetic head, an escape groove for a mixed lubricant is formed at the boundary between the inner periphery 2 and the outer periphery 3. together provided a magnetic recording medium body, characterized in that is excellent in impact resistance than the lubricant 4 covering the inner peripheral portion 2 lubricant 5 covering the outer peripheral portion 3.
(Supplementary Note 2) The thickness of the outer peripheral portion 3 lubricant 5 which covers the, Appendix 1 Symbol placement of the magnetic recording medium characterized by being thicker than the thickness of the lubricant 4 which covers the inner peripheral portion 2.
(Supplementary note 3 ) The magnetic recording medium according to Supplementary note 1 or 2 , wherein a lubricant containing a phosphorus-containing fluorine compound is used as the lubricant 5 covering the outer peripheral portion 2.
(Additional remark 4 ) In the manufacturing method of the magnetic recording medium 1 which consists of the inner peripheral part 2 which performs recording, and the outer peripheral part 3 which loads a magnetic head, in the state which coat | covered the said inner peripheral part 3 with the mask, the said outer peripheral part 3 1 in which the lubricant 5 is coated by either a dipping method or a spray coating method, and the outer peripheral portion 3 is covered with a mask, and the inner peripheral portion 2 is more shock resistant than the first lubricant 5. And a step of coating the inferior second lubricant 4 by either a dipping method or a spray coating method.
(Supplementary Note 5 ) A magnetic field comprising an inner peripheral portion 2 for recording and an outer peripheral portion 3 for loading a magnetic head, and a relief groove 6 for the lubricants 4 and 5 is provided at the boundary between the inner peripheral portion 2 and the outer peripheral portion 3. In the manufacturing method of the recording medium 1, the first lubricant 4 is dropped on the inner peripheral portion 2, and the second lubricant 5 having higher impact resistance than the first lubricant 4 is applied to the outer peripheral portion 3. A method for producing a magnetic recording medium, characterized by dripping and spin coating.
(Supplementary Note 6 ) A magnetic recording apparatus including the magnetic recording medium 1 according to any one of Supplementary notes 1 to 3 .
[0046]
【The invention's effect】
As described above, according to the present invention, since the lubricant provided on the outer peripheral portion of the magnetic disk is a lubricant having higher impact resistance than the lubricant provided on the inner peripheral portion, the ramp loading / unloading mechanism is provided. In the magnetic disk device, it is possible to prevent the occurrence of damage due to an impact when the magnetic head is loaded. As a result, the high recording density magnetic disk device greatly contributes to extending the life and improving the reliability.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a basic configuration of the present invention.
FIG. 2 is an explanatory diagram of the manufacturing process up to the middle of the magnetic disk according to the first embodiment of this invention;
FIG. 3 is an explanatory diagram of the manufacturing process after FIG. 2 for the magnetic disk according to the first embodiment of the invention;
FIG. 4 is a configuration explanatory diagram of a magnetic disk device according to a second embodiment of this invention.
FIG. 5 is an explanatory diagram of a loading operation of a magnetic head by a ramp loading / unloading mechanism.
FIG. 6 is a schematic sectional view of a conventional magnetic disk.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Magnetic recording medium 2 Inner peripheral part 3 Outer peripheral part 4 Lubricant 5 Lubricant 6 Escape groove 10 Magnetic disk 11 Inner peripheral part 12 Outer peripheral part 21 Glass substrate 22 Escape groove 23 NiP layer 24 CrMo underlayer 25 CoCrPt magnetic recording layer 26 DLC protective film 27 lubricant 28 lubricant
41 Housing 42 Spindle motor 43 Lift tab 44 Suspension 45 Magnetic head 46 Carriage 47 Actuator 48 Ramp 49 Ramp 50 Horizontal path 51 Stop part 61 Ramp 62 Ramp 63 Horizontal path 64 Stop part 65 Magnetic head 71 Magnetic disk 72 Landing area 73 Glass substrate 74 NiP layer 75 CrMo underlayer 76 CoCrPt magnetic recording layer 77 DLC protective film 78 Lubricant

Claims (5)

In a magnetic recording medium comprising an inner periphery for recording and an outer periphery for loading a magnetic head , a lubricant relief groove is provided at the boundary between the inner periphery and the outer periphery, and a lubricant covering the outer periphery is provided. A magnetic recording medium characterized by being superior in impact resistance to a lubricant covering the inner peripheral portion . The thickness of the lubricant covering the outer peripheral portion, the magnetic recording medium of claim 1 Symbol mounting characterized by being thicker than the thickness of the lubricant covering the inner peripheral portion. As a lubricant for coating the outer peripheral portion, the magnetic recording medium according to claim 1 or 2, characterized in that a lubricant containing a phosphorus-containing fluorine compound. In the method for manufacturing a magnetic recording medium, which comprises an inner peripheral part for recording and an outer peripheral part for loading a magnetic head, and a relief groove for a lubricant is provided at the boundary between the inner peripheral part and the outer peripheral part. A method for producing a magnetic recording medium, wherein a first lubricant is dropped, and a second lubricant having higher impact resistance than the first lubricant is dropped onto the outer peripheral portion and spin-coated. . The magnetic recording apparatus characterized by mounting the magnetic recording medium according to any one of claims 1 to 3.

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