JPH033106A - Disk for polishing magnetic disk - Google Patents

Abstract

PURPOSE:To polish the magnetic recording medium sliding surface of a magnetic head in a condition in which the magnetic head is mounted on a magnetic disk driver by using a disk for polishing in which the outer circumferential part and inner circumferential part of a polishing sheet having a flexibility, whose flexural rigidity is <=0.5Nmm, are stretchingly fixed to a rigid substrate. CONSTITUTION:For a disk 36 for polishing a magnetic head, polishing sheets 34 and 35, whose flexural rigidity is <=0.5Nmm, are stretchingly fixed insead of magnetic sheets 10 and 11 on the surface of a rigid substrate 9 to the same one used for a magnetic disk 8. Consequently, the disk 36 for polishing is incorporated in the magnetic disk driver in the same way as the ordinary magnetic disk 8, a magnetic disk 22 of the magnetic disk driver is brought into contact with the polishing sheet 35 of one side, the polishing disk 36 is rotated, and then, a magnetic recording medium sliding surface 32 of the magnetic head 22 is polished. Consequently, the magnetic head 22 can be polished in a condition in which it is mounted on the magnetic disk driver, and the removing and incorporating works of the magnetic head 22 can be omitted.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention brings a magnetic head supported by parallel springs into contact with a magnetic disk formed by a flexible magnetic sheet stretched over a rigid base. The present invention relates to a magnetic bend polishing disk suitable for polishing the sliding surface of a magnetic recording medium of a magnetic head mounted on a magnetic disk drive iJ+ device that performs recording and/or reproduction.

[Prior Art] Magnetic disks, which are disk-shaped magnetic recording media, include so-called hard disks whose substrates are made of hard materials such as aluminum alloys, and flexible magnetic disks whose substrates are made of flexible resin films such as polyester. So-called floppy disks) are well known, and are widely used as external storage media for computers, word processing sensors, and the like.

By the way, these hard disks, floppy disks, etc. have advantages and disadvantages in terms of contact with the magnetic head, dimensional stability, etc.

Therefore, in recent years, as described in, for example, Japanese Patent Application Laid-open No. 151838/1983, magnetic disks that have the features of the above-mentioned hard disks and floppy disks, that is, flexible magnetic sheets on a disk-shaped rigid base, have been developed. 2. Description of the Related Art There have been proposals for a magnetic disk that is stretched by fixing an outer circumferential portion and an inner circumferential portion.

The above-mentioned magnetic disk has a magnetic sheet stretched over an annular recess provided on the surface of a rigid base in a so-called drum-stretched state, so that the magnetic head does not directly hit the hard base 1 against the base. It is superior to hard disks in that there is less load on the magnetic head. On the other hand, the above magnetic disk does not require a pressure pad,
It is superior to a floppy disk in that the recording surface has dimensional stability between the rigid substrate to which it is attached and the distance between the disks.

By the way, in order to perform recording and/or playback on this type of magnetic disk, a composite type magnetic disk in which a magnetic head is embedded in a non-magnetic member called a slider, which is usually used in hard disks, etc. is used. The head is spaced at a constant distance from the magnetic disk surface.

However, in the above-mentioned magnetic disk, since the magnetic sheet may cause surface runout during recording and reproduction, the distance between the head and the magnetic disk surface fluctuates, making it impossible to ensure stable flying of the head. Therefore, a problem arises in that the reproduction output is significantly reduced.

Therefore, the applicant of the present application has proposed a system that can perform recording and/or playback effectively on this type of 6N disc.

As shown in Figure 6, this system uses a magnetic disk (
Recording and/or reproduction is performed by bringing a magnetic head (4) supported by parallel wings (2) and (3) to the magnetic disk surface (la) into contact with the magnetic disk surface (la).

That is, the magnetic disk drive device here includes two temporary springs (2) disposed substantially parallel to the magnetic disk surface (1a).
) and (3), and a magnetic head (4) is attached and fixed to the tip of the temporary spring (2).
, (3), and a movable part elastically biased in a direction substantially perpendicular to the magnetic disk surface (1a).

The magnetic head support section includes two plate bars 2 (2),
(3), and a support frame (5) for fixing the leaf springs (2) and (3), with a slit groove machined in one side (5a) of the notch of the support frame (5). These two leaf springs (2) and (3) are arranged in parallel in the vertical direction at a predetermined interval. In addition, the above leaf spring (
2).

(3) When disposed on the support frame (5), the surfaces of the plate springs (2) and (3) in the 'Fi thickness direction are substantially parallel to the magnetic disk surface (1a). .

On the other hand, the movable part includes a magnetic head (4) that performs recording and reproduction by contacting the magnetic disk surface (1a), and the magnetic head (4).
The head mounting is made up of a plate (6) and an elastic member (7) that suppresses resonance, and the rectangular head mounting vi,
The magnetic head (4) is attached and fixed to one longitudinal edge of (6), and an elastic member is brought into contact with the other edge.

In order to mount the head, the plate (6) is supported by the two 1 anti-springs (2) and (3), and the magnetic head (
4) is elastically biased in a direction substantially orthogonal to the magnetic disk surface (la).

In the magnetic disk drive device configured in this way, the magnetic head (4) is configured to move up and down in a direction substantially perpendicular to the magnetic disk surface (la).
It is possible to follow the surface runout of the magnetic disk surface (1a), and a good contact state is always ensured. therefore,
If this device is used to perform recording and reproduction on the above-mentioned magnetic disk (1), the reduction in reproduction output due to spacing loss and the like can be minimized.

(Problems to be Solved by the Invention) In the above system, the radius of curvature of the magnetic recording medium sliding surface (4a) of the magnetic head (4) is important, and depending on the size of the radius of curvature, the playback output and the sliding surface Therefore, in this type of magnetic head (4), the radius of curvature of the magnetic recording medium sliding surface (4a) is required to be a predetermined size.

Therefore, it is necessary to polish the magnetic recording medium sliding surface (4a) of the magnetic head (4) from time to time. Head (4
), first remove the magnetic head (4) from the magnetic disk drive described above, and then use a dedicated polisher to polish the magnetic recording medium sliding surface (4a).
This is done by incorporating the magnetic head (4) into the magnetic disk drive device again.

In this way, the magnetic recording medium sliding surface (
The polishing operation 4a) requires removal and installation of the magnetic head (4), and requires positioning each time, which is troublesome. In addition, the removed magnetic head (
4) needs to be polished using a special polishing machine,
There are problems such as the need to manufacture the polishing machine.

The present invention has been proposed in view of the above-mentioned conventional circumstances, and allows polishing of the magnetic recording medium sliding surface of a magnetic head while it is mounted on a magnetic disk drive, with simple operation. It is an object of the present invention to provide a disk for a magnetic head gIQ that can maintain the reproduction output of the magnetic head and high durability.

[Means for Solving the Problems] The present invention has been proposed to achieve the above-mentioned object, and includes a flexible abrasive sheet that fixes the outer and inner peripheral portions of the rigid substrate. The polishing sheet has a bending rigidity of 0.5 mm or less.

[Effect]

The magnetic head polishing disk of the present invention has a flexible polishing sheet stretched around a rigid base by fixing the outer and inner peripheral portions to form a disk shape. Therefore, this magnetic head polishing disk is supported by parallel springs, similar to a magnetic disk in which a normal flexible magnetic sheet is stretched around a rigid base by fixing the outer and inner circumferences. By bringing the magnetic head into contact with the surface of the magnetic disk, the magnetic head can be attached to a magnetic disk drive device that performs recording and/or reproduction. Therefore, if a magnetic head mounted on a magnetic disk drive device is brought into contact with the polishing sheet and the magnetic head polishing disk is rotated in the same way as when recording and reproducing a normal magnetic disk, the magnetic head can be attached to the magnetic disk. The sliding surface of the magnetic recording medium can be polished while it is mounted on the drive device. At this time, since the bending rigidity of the polishing sheet of the magnetic head polishing disk is optimized, the sliding surface of the magnetic recording medium is polished to a radius of curvature that can maintain high reproduction output and high durability.

[Example] Hereinafter, specific examples to which the present invention is applied will be described.

First, a system to which a magnetic head polishing disk according to the present invention is applied will be described with reference to the drawings.

As shown in Fig. 1, the above system uses a parallel bar against a magnetic disk, which is made up of a flexible magnetic sheet stretched over a disk-shaped rigid base by fixing the outer and inner circumferential parts. This is a magnetic disk drive device having a magnetic head supported by a magnetic head, and recording and/or reproduction is performed by bringing the magnetic head into contact with the magnetic head.

As shown in FIG. 2, the magnetic disk (8) has a flexible magnetic 'i' on both sides of a disk-shaped rigid base (9).
-) (10), (11) It is constructed by fixing to the outer circumference and inner circumference with an adhesive or the like at a predetermined penetration stiffness.

The rigid base (9) includes a center core portion (12) for mounting the spindle shaft, and the magnetic sheet (10).
, (11), and annular annular convex portions (14) along the outermost and innermost peripheral edges of both sides of the supporting portion (13), respectively. (
15), (16), and (17) are provided. In other words, the supporting portion (13) has annular recesses (18) and (19) each having a wide and shallow groove formed on both sides thereof. The recessed portion (1B>, '(19)) is
The groove is formed as an escape groove to alleviate an accidental impact on the magnetic head, and its shape is not particularly limited.

The material for the rigid base (12) is preferably one with a low coefficient of thermal expansion, and any material conventionally used as a base material for this type of magnetic disk can be used, and is not particularly limited. Examples include aluminum, aluminum alloy, thermoplastic resin, and unsaturated polyester resin. Further, polyarylate resins having a coefficient of thermal expansion close to those of metal materials used as base materials for general hard disks, polyetherimide resins having excellent mechanical properties, heat resistance, processability, etc. can also be used.

Further, the annular convex portion (1) on the outermost peripheral edge of the support portion (13)
4) and the annular protrusion (16) on the innermost periphery, or between the annular protrusion (15) on the outermost periphery and the annular protrusion (16) on the innermost periphery.
17), the annular recesses (18) and (19)
Magnetic sheets (10) and (11) are attached in a so-called drum-stretched manner so as to cover them. Note that the magnetic sheets (10) and (11) are attached to the support portion (13) using an epoxy adhesive or an acrylic adhesive.
is fixed.

The magnetic sheets (10) and (11) have a magnetic layer formed on the surface of a flexible non-magnetic support 2 such as a polyethylene terephthalate film or a polyimide film. Such a magnetic layer may be of a coating type conventionally used in the field of magnetic recording, or a thin metal magnetic layer formed by vapor deposition or the like.

Three metal magnetic films (for example, Co-Cr, Co-Ni)
A perpendicularly magnetized film or the like is used, which is formed by depositing a strong 6n metal material such as an alloy by vacuum thin film forming techniques such as vapor deposition or sputtering.

Note that a protective film layer, a lubricant layer, etc. may be formed on the magnetic layer as necessary.

In particular, when a metal magnetic thin film is used as the magnetic layer, the magnetic sheets (10) and (11) are determined by setting the thickness of the non-magnetic support to δ (μm) and fixing the magnetic sheets (10) and (11). Veneration stiffness is 90・δ/Δr (a+g/μm) when the radius difference between the parts is Δr (m).
It is desirable to install it so that the following conditions are met. This value of penetration stiffness is determined by the magnetic sheet (10
), (11) is the upper limit at which no scratches are observed in the metal magnetic film formed on the non-magnetic support when stretched on the rigid substrate (12). Therefore, if the above-mentioned magnetic sheet (10), <11) is stretched on the above-mentioned rigid base (12) below this value, it becomes possible to provide a magnetic disk (1) having a metal magnetic thin film without cracking. .

On the other hand, the magnetic disk drive device includes the magnetic disk (8).
) two temporary springs (20) arranged so as to be substantially parallel to the magnetic disk surface (8a) which is the magnetic recording medium surface;
(21), and a magnetic head (22) is attached and fixed to the tip of the temporary spring (20).
, (21), and a movable part elastically biased in a direction substantially perpendicular to the magnetic disk surface (8a).

The magnetic head support section has two plate wings (20) and (21).
) and a support frame (23) that fixes these two leaf springs (20) and (21).

The temporary springs (20) and (21) are formed by photo-etching a thin plate of stainless steel or the like into a substantially triangular shape with notches (24) and (25) at one vertex. It is something that In addition, the above temporary spring (
20) The shapes of (21) are not particularly limited, and may be rectangular or the like.

What is important here is the blade constant in the plate thickness direction (movement direction). That is, in the temporary springs (20) and (21), the spring constant is set to 5.6xlO-5g/μm or more and 0.09g/μm or less.

This is the range in which the magnetic head (22) can follow this surface deflection even if the magnetic disk surface (8a) is deflected due to the rotation of the magnetic disk (8). Therefore, the magnetic head (22)
The magnetic disk surface (8a) is always in contact with a substantially uniform head load. Furthermore, this leaf spring (2
In addition to the magnitude of the spring constant in the J direction of 0) and (21), the stiffness of the leaf spring in the direction perpendicular to the direction of movement of 0'') and (21) is also important. When the spring constant of the magnetic head (2
2) Rigidity in the track direction [radial direction of the magnetic disk (8)] is ensured, and a decrease in reproduction output due to track misalignment is suppressed.

Further, even when recording and reproducing are performed by shifting the magnetic head (22) in the radial direction of the magnetic disk (8), the edge of the magnetic head (22) is located on the magnetic disk surface (8a).
) will not hurt.

The support frame (23) is made of a highly rigid material and has a fan shape with a notch (26) in the center. Note that the shape of the support frame (23) is not particularly limited, and the support frame (23) must be stably fixed so as not to hinder recording and reproduction of the magnetic head (22) on the magnetic disk (8). If possible, it is not limited to this example. Furthermore, slit grooves (27) and (2B) are formed in the outer circumference (23a) and inner circumference (23b) of the support frame (23), respectively. The slit grooves (27) and (28) are connected to the temporary springs (
20) and (21), the leaf springs (20) and (21) touch the magnetic disk surface (8a).
It is formed so that it is approximately parallel to. Therefore, the leaf springs (2
0) and (21) and fix it with adhesive etc., the leaf spring (20) will be formed.

(21) and the magnetic disk surface (8a) are approximately parallel to each other.

The movable part consists of a magnetic head (22) that performs recording and reproduction on the magnetic disk (8), and a head mounting plate (29) that mounts and fixes the magnetic head (22) at its tip.

As shown in FIG. 3, the magnetic head (22) has a pair of magnetic cores (30), (31) forming a closed magnetic path.
) are butted against each other, and a magnetic gap g is formed on the magnetic recording medium sliding surface (32).

The magnetic core half-holes (30) and (31) are made of a substrate made of, for example, an oxide magnetic material, similar to the magnetic core half-holes of a magnetic head installed in a magnetic recording/reproducing device such as an ordinary video tape recorder. The material is not limited in any way and any conventionally known material can be used. In addition, the above magnetic core half-break (30),
A ferromagnetic metal thin film made of sendust or the like may be formed on the abutting surface of (31). In this case, the magnetic core half-holes (30) and (31) are made of a non-magnetic material. It does not matter if it is a magnetic material. Note that the winding groove (33) for winding the coil may be formed in either one of the magnetic core halves (30).

In particular, in the magnetic head (22), the radius of curvature R of the magnetic recording medium sliding surface (32) is preferably 3 or more and 50[1 or less, more preferably 5IIn or more and 30 or less. This shows the relative playback output and sliding durability of the magnetic head when the applicant previously performed recording and playback on the above-mentioned magnetic disk (8) by changing the radius of curvature R of the magnetic head (22). This is based on the results of determining the dependence on the radius of curvature.

That is, as shown in FIG. 4, the relative reproduction output tends to decrease as the radius of curvature R becomes larger, and the sliding durability tends to deteriorate as the radius of curvature R becomes smaller. Therefore, in order to satisfy the relative reproduction output and the sliding durability at the same time, the relative reproduction output should be within a range that does not decrease by 3 dB or more, preferably 1.5 dB or more, compared to the maximum output. The radius of curvature R at this time is 5
9m [a, 3011! It is. Furthermore, the sliding durability should be within a range of 100,000 busses or less, preferably 1,000,000 busses or less, compared to the durability of 10 million busses or more. The radius of curvature R at this time is 3fi11.5M.

Therefore, in order to record and reproduce information on this type of magnetic disk, the magnetic recording medium sliding surface (3) of the magnetic head (22) must be
If the radius of curvature R of 2) is set to 3 m or more and 50 am or less, preferably 5 m or more and 30 am or less, high reproduction output and high durability can be expected.

In addition, the head mounting plate (29) for fixing the magnetic head (22) is made of a thin plate of non-magnetic stainless steel, for example, about 0.1 mm thick, by photo-etching in order to reduce the mass of the head part. It is formed into a rectangular shape using a method such as the following. The above-mentioned head mounting plate (29) fixes the magnetic head (22) at the leading end of the longitudinal direction, and furthermore, the above-mentioned plate spring (20) is attached to the middle part in the longitudinal direction.
, (21) are formed into slit grooves (not shown) for inserting and fixing them. Therefore, the previous leaf springs (20) and (21) are inserted here, and these heads are attached using adhesive or the like.
), (21) are fixed in one piece.

As a result, the magnetic head (32) is elastically biased in a direction substantially perpendicular to the magnetic disk surface (8a) by the plate springs (20) and (21) via the plate (29). Ru. That is, the leaf springs (8) and (9
), the magnetic head (22) can move up and down in a direction substantially perpendicular to the magnetic disk surface (8a) (direction of arrow Y in the figure).

In the magnetic disk drive device configured as described above, a temporary spring (2
0) and (21) so that the magnetic head (22) is elastically biased in a direction substantially perpendicular to the magnetic disk surface (8a).
8a) Even if there are irregularities on the surface, the magnetic head (22) can follow the bumps, and the head (22) and the magnetic disk surface (8a) are always in contact with a constant head load. It is possible to ensure good contact conditions.

Therefore, changes in the head load on the magnetic disk surface (8a) are suppressed, and damage to the magnetic disk surface (8a) due to loss of the envelope or high load is suppressed.

Next, a magnetic head polishing disk for polishing the magnetic recording medium sliding surface (32) of the magnetic head (22) mounted on the magnetic disk drive device in the above system will be described.

As shown in FIG.
In place of the magnetic sheets (10) and (11), polishing sheets (34) and (35) are stretched over the surface of the magnetic sheet. Therefore, the rigid base (8) is
Exactly the same magnetic disk (8) as described above can be used.

The abrasive sheets (34) and (35) are made of, for example, Cr which is an abrasive on a polyethylene terephthalate film.
, 03, etc. are formed. In particular, the polishing sheets (34) and (35) are attached so that the bending rigidity is 0.5N- or less. This means that if the bending rigidity of the abrasive sheets (34) and (35) is 0.5 mm or less, the magnetic recording medium sliding surface (32) can be polished for the magnetic head, which can simultaneously satisfy high reproduction output and high durability. This is because it can be formed by the disc (36).

A magnetic head polishing disk (36
) can be incorporated into the above-mentioned system in the same way as a normal magnetic disk (8). Then, in the same way as recording and reproducing the magnetic disk (8), the magnetic head (22) of the magnetic disk drive device is brought into contact with one polishing seat (35) of the magnetic head polishing disk (36). By rotating the magnetic head polishing disk (36), the magnetic recording medium sliding surface (32) of the magnetic head (22) is polished. Therefore, the magnetic head (22) can be polished while being mounted on the magnetic disk drive device, and the work of removing and assembling the magnetic head (22) can be omitted. Further, there is no need to manufacture a dedicated polishing machine for polishing the magnetic recording medium sliding surface (32).

Here, magnetic head polishing disks (36) with various bending rigidities of the polishing sheets (34) and (35) were prepared as follows, and this 6d air head polishing disk (36) was used as described above. A magnetic recording medium sliding surface (32) of a magnetic head (22) mounted on a magnetic disk drive device of
Polished.

First, CrzOz was applied to the surface of the disk-shaped rigid substrate (9) shown in FIG. 2, covering the recesses (18) and (19).
Polishing sheets (34) and (35) made of polyethylene terephthalate films formed with are attached so that the bending stiffness thereof is in the range of I x 10-'Nmc+ to 0.6 N+++a+, and magnetic heads having various bending stiffnesses are prepared. A polishing disk (36) was produced.

Next, the magnetic henodic polishing disk (36) is assembled into the magnetic disk drive device, and one polishing sheet (36) is assembled into the magnetic disk drive device.
5) was brought into contact with the magnetic head (22), and polishing was performed by rotating the magnetic head polishing disk (36).

At this time, the head protrusion amount of the magnetic head (22) was 50 μm, the rotation speed of the magnetic head polishing disk (36) was 20 Orpm, and the polishing time was 4 to 5 seconds. Further, the spring constant of the temporary springs (20) and (21) in the movable direction was 0.01 g/μm.

Then, the radius of curvature R of the magnetic recording medium sliding surface (32) of the obtained magnetic head (22) was measured. The result is the fifth
As shown in the figure, gland a in Figure 5 is the maximum value.

Lines indicate minimum values.

As can be seen from this result, the polishing sheets (34) (35
), when the bending stiffness value of
Accordingly, the radius of curvature R of the magnetic recording medium sliding surface (32) of the magnetic head (22) to be polished also gradually becomes smaller.

For example, when the bending rigidity of the polishing sheets 1-(34) and (35) is 0.5 Nan, the radius of curvature R of the magnetic recording medium sliding surface (32) is approximately 40 mm (minimum value), and the bending rigidity is I x 10 -N■ has approximately 5 cabinets (minimum value).

Next, magnetic heads (
22) was actually used to perform recording and reproduction on the magnetic disk (8) using the above system.

The above magnetic disk was coated with a Co-Cr perpendicular magnetization film with a thickness of 0.2 μm on a polyimide film with a thickness of 40 μm, a carbon protective film of 100 people, and a fluorine-based lubricant layer (product name: Phoneprin AM2001) of 30 to 50 people. The magnetic sheets (10) and (11) thus formed were stretched over a disk-shaped rigid substrate (9) shown in FIG. 2, and the magnetic sheets were used.

As a result, if the radius of curvature R of the magnetic recording medium sliding surface (32) of the magnetic head (22) is 40 μm or more, it becomes difficult to make contact between the gap portion and the magnetic disk surface (8a), resulting in a decrease in reproduction output. was seen. Of course, even if the radius of curvature R of the sliding magnetic recording medium (32) is about 50 m1, this does not pose a problem on a practical level as described above. On the other hand, when the radius of curvature R of the magnetic recording medium sliding surface (32) was less than 5 mm, the pressure at the tip of the head suddenly increased and the sliding durability deteriorated. The polishing sheet at this time (3
The bending stiffness of 5) is 0.5 Non, I, respectively.
X 10-"NWm. Therefore, in order to obtain a magnetic head (22) that can simultaneously satisfy high reproduction output and high durability, at least the magnetic head polishing disk (36)
The bending rigidity of the polishing sheet (35) may be 0.5 NffIl or less.

(Effects of the Invention) As is clear from the above description, in the magnetic head polishing disk of the present invention, the polishing sheet is stretched over a rigid base with the outer and inner peripheral portions fixed, thereby making it possible to use normal magnetic head polishing. Since it is shaped like a disk, it can be incorporated as is into a magnetic disk drive device that supports a magnetic head with parallel springs, and magnetic bed polishing can be performed in the same way as recording and reproducing on a normal magnetic disk. By rotating the magnetic disk and bringing the magnetic head into contact with the polishing sheet, the sliding surface of the magnetic recording medium can be polished while the magnetic head remains mounted on the magnetic disk drive device. Since the abrasive sheet has optimized bending rigidity, it is possible to provide a magnetic head having a magnetic recording medium sliding surface that can maintain high reproduction output and high durability.

Therefore, by using the magnetic head polishing disk of the present invention, it is possible to omit the work of removing and assembling the magnetic head during repolishing, and it is possible to improve work efficiency. Furthermore, there is no need to manufacture a dedicated polishing machine for polishing the sliding surface of the magnetic recording medium.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view of a main part showing an example of a magnetic disk drive device to which a magnetic head polishing disk of the present invention is applied;
FIG. 2 is a sectional view showing an example of the configuration of a magnetic disk and a magnetic head polishing disk mounted on a magnetic disk drive, and FIG. 3 is a side view showing an example of a magnetic head mounted on a magnetic disk drive. Figure 4 is a characteristic diagram showing the dependence of the relative reproduction output and sliding durability on the radius of curvature of the magnetic head, Figure 5 is a characteristic diagram showing the dependence of the bending rigidity of the polishing sheet on the radius of curvature of the magnetic head, and Figure 6 is the conventional 1 is a schematic perspective view of main parts showing an example of a magnetic disk drive device of FIG. 36 ・ 9 ・ ・ 4 22 ・ 0 ・・Magnetic head polishing disk・rigid substrate 35 ・・polishing sheet ・・magnetic head 21 ・・plate spring

Claims (1)

[Claims] For magnetic head polishing, characterized in that a flexible polishing sheet is stretched over a rigid base by fixing the outer and inner peripheral parts, and the bending rigidity of the polishing sheet is 0.5 mm or less. disk.