JP3396476B2 - Magnetic transfer device and method of manufacturing magnetic recording medium - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic transfer device which uses a master information carrier to pre-record a predetermined information signal on a magnetic recording medium used in a magnetic recording / reproducing device having a large capacity and a high recording density, and The present invention relates to a method for manufacturing a magnetic recording medium.

[0002]

2. Description of the Related Art At present, a magnetic recording / reproducing apparatus tends to have a high recording density in order to realize a small size and a large capacity. In the field of hard disk drives, which are typical magnetic disk devices, the areal recording density is already 10 Gb.
Devices exceeding it / sqin have been commercialized, and one year later, a rapid technological advance is recognized to the extent that a device having an areal recording density of 20 Gbit / sqin is expected to be put into practical use.

The technical background of enabling such a high recording density is a magnetoresistive element type which can reproduce a signal having a track width of only a few μm with a good SN characteristic while improving the linear recording density. It depends largely on the head.

Further, as the recording density has increased, it has been required to reduce the flying height of the floating magnetic slider with respect to the magnetic recording medium, and there is an increased possibility that the disk / slider contact may occur for some reason during the flying. There is. Under such circumstances, the recording medium is required to have a higher smoothness.

The head tracking servo technique plays an important role for the head to accurately scan a narrow track. In a current hard disk drive using such a tracking servo technique, a tracking servo signal, an address information signal, a reproduction clock signal, etc. are recorded on a magnetic recording medium at regular angular intervals. The drive device detects and corrects the position of the head based on these signals reproduced from the head at regular time intervals, thereby enabling the head to accurately scan the track.

Here, as described above, the servo signal, the address information signal, the reproduction clock signal, and the like serve as reference signals for the head to accurately scan the track, so that they are written (hereinafter referred to as formatting). (Note) requires high positioning accuracy. In the current hard disk drive, formatting is performed by positioning the recording head using a dedicated servo device (hereinafter referred to as a servo writer) incorporating a high-precision position detection device using optical interference.

[0007]

However, there are the following problems in the above-mentioned formatting by the servo writer.

First, the recording by the magnetic head is basically line recording based on the relative movement between the magnetic head and the magnetic recording medium, and since it is necessary to write a signal over many tracks, the method by the servo writer is not used. In addition, it takes a lot of time to perform preformat recording, and a plurality of expensive dedicated servo writers are required to improve productivity, and preformat recording is expensive.

Secondly, a large amount of cost is required to introduce and maintain many servo writers. These problems became more serious as the track density increased and the number of tracks increased. Therefore, the formatting is performed not by the servo writer, but by overlaying a disk called master in which all servo information is written in advance with a magnetic disk to be formatted, and applying an external magnetic field for transfer from the outside, the master information is magnetically transferred. A method of batch transfer onto a disc has been proposed.

As one example thereof, Japanese Patent Laid-Open No. 10-40544
The magnetic transfer method disclosed in Japanese Patent Publication is cited. In the publication, a magnetic portion made of a ferromagnetic material is formed on a surface of a base body in a pattern shape corresponding to an information signal to form a master information carrier, that is, a master for magnetic transfer, and the surface of this master information carrier is By contacting the surface of a sheet-shaped or disk-shaped magnetic recording medium on which a ferromagnetic thin film or a ferromagnetic powder coating layer is formed, and applying a predetermined external magnetic field,
A method of recording a magnetic pattern having a pattern shape corresponding to an information signal formed on a master information carrier on a magnetic recording medium is disclosed.

FIG. 32 shows an example of conventional steps of initial magnetization and transfer of a magnetic recording medium in such a magnetic transfer system. FIG. 33 shows the relationship between the rotation phase of the magnetic head for generating an external magnetic field, the distance between the magnetic head gap and the surface of the magnetic recording medium, and the magnetic head rotation speed. When the magnetic head approaches or separates from the magnetic recording medium,
The magnetic head is not rotationally driven, but is driven only in the approaching and separating directions. On the other hand, at the time of initial magnetization and transfer, the magnetic head rotates around a substantially central portion of the magnetic recording medium in order to apply a magnetic field to the magnetic recording medium. Therefore, in the conventional method, the approaching / separating operation of the magnetic head and the initial magnetizing / rotating operation for transfer are performed completely independently.

Such a magnetic transfer method is a method of collectively recording an array pattern corresponding to an information signal provided on a master information carrier as a magnetization pattern on a magnetic recording medium, but it is stable and stable over the entire magnetic recording medium. It is important that the density information signal is recorded.

In the conventional magnetic transfer system as described above, the magnetic head for transfer is kept stationary with respect to the contact body between the master information carrier and the magnetic recording medium, and then separated. Therefore, there is a problem that the recording signal is deteriorated (a large fluctuation of the reproduction peak level) at the portion corresponding to the transfer magnetic head (the phase position of 450 degrees in FIG. 33).

FIG. 34 shows the peak value of the reproduction signal voltage with respect to the magnetic recording medium rotation phase. The horizontal axis of this figure shows the vicinity of the magnetic head separation phase, and the numerical values are omitted. This also applies to FIG. 21 described below. FIG. 35 shows a reproduction signal waveform in the separation phase of the transfer magnetic head. The horizontal axis and the vertical axis respectively show the time and the reproduction signal voltage. In FIG. 34, a portion where the peak value of the reproduction signal is low is seen as shown by the arrow. FIG. 35 shows the reproduced signal waveform of this portion. As can be seen from FIG. 35, the voltage v2 is much lower than the voltage v1, and it can be seen that the reproduced signal is deteriorated. Therefore, in that portion, the signal-to-noise ratio (S / N) is lowered and the error rate is increased.

As described above, in the conventional system, the reproduction signal voltage is lowered in the separation phase of the transfer magnetic head.
Although the magnetic transfer recording is performed by an external magnetic field component horizontal to the master information carrier, an external magnetic field component vertical to the master information carrier is actually applied due to the structure of the magnetic head. The deterioration of the recording signal as described above occurs
This is because the influence of the vertical component is not canceled in the separated phase of the transfer magnetic head.

The deterioration of the recording signal in the transfer magnetic head separation phase tends to increase as the strength of the applied external magnetic field increases. On the other hand, the coercive force of the magnetic recording medium tends to increase with future improvement in recording density, and therefore it is necessary to naturally increase the strength of the external magnetic field applied. Therefore, it is considered that the degree of deterioration of the recording signal described above will increase more and more in the future, and the solution of this problem is indispensable in the future.

The present invention has been made in view of the above problems, and provides a highly reliable magnetic transfer device and a method of manufacturing a magnetic recording medium, which does not cause signal deterioration at the position where an external magnetic field is removed. The purpose is to provide.

[0018]

In order to achieve the above object, a magnetic transfer apparatus of the present invention comprises a master information carrier having a ferromagnetic material corresponding to an information signal formed on the surface of a substrate, and a ferromagnetic layer. In the close contact body that is in close contact with the existing magnetic recording medium,
In a magnetic transfer device for applying a magnetic field by a magnetic field generating means to transfer an information signal of the master information carrier to the magnetic recording medium, the magnetic field generating means while relatively rotating the magnetic field generating means and the contact body. a drive means for adjusting the distance between the contact member and, setting of the driving means
Is close to the magnetic field generating means and the surface of the contact body.
Move to the position and rotate the magnetic recording medium about the center.
Of the magnetic field generating means and the contact body,
By rotating at least one of the magnetic field generating means,
Rotate relative to the contact body to drive the rotation.
While continuing, the magnetic field generating means to the contact body
It is characterized in that it is set to be separated .

According to the magnetic transfer device as described above, the external magnetic field is applied to or removed from the transfer of the information signal of the master information carrier to the magnetic recording medium while rotating the magnetic field generating means with respect to the contact body. Therefore, it is possible to prevent deterioration of the reproduction signal of the magnetic recording medium.

Next, another magnetic transfer device according to the present invention is
Master with ferromagnetic material corresponding to information signal formed on the surface
-Adhesion between information carrier and magnetic recording medium with ferromagnetic layer
A magnetic field is applied to the adhered body by the magnetic field generation means before
The information signal of the master information carrier is transferred to the magnetic recording medium.
In the magnetic transfer device for copying, the magnetic field generation means and the
The magnetic field generating means while rotating the contact body relatively.
And a driving means for adjusting the distance between the contact body and the contact body. The setting of the driving means is performed by moving to a position where the magnetic field generating means and the surface of the contact body are close to each other, and a substantially central portion of the magnetic recording medium With at least one of the magnetic field generating means and the contact body as a rotation center, the magnetic field generating means is rotated relative to the contact body.
After at least by rotating the relative rotation, while continuing the rotation drive, characterized in that said magnetic field generating means is set to be away from the said contact body. According to the magnetic transfer device as described above, it is possible to prevent the deterioration of the transfer recording signal in the phase where the magnetic head is separated, and it is possible to perform uniform transfer recording on the entire surface of the magnetic recording medium.

Further, the movement to a position where the magnetic field generating means and the surface of the close contact body come close to each other is such that at least one of the magnetic field generating means and the close contact body is rotated about the center of the magnetic recording medium. It is preferable that the magnetic field generating means is rotationally driven to rotate the magnetic field generating means relative to the contact body. According to the magnetic transfer device as described above, it is possible to prevent the transfer recording signal from being deteriorated even when the magnetic head is approached, so that the uniform transfer recording on the entire surface of the magnetic recording medium becomes more reliable.

Next, still another magnetic transfer apparatus of the present invention brings a master information carrier having a ferromagnetic material corresponding to an information signal formed on the surface of a substrate and a magnetic recording medium having a ferromagnetic layer into close contact with each other. In a magnetic transfer device for applying a magnetic field to the contact body by magnetic field generation means to transfer the information signal of the master information carrier to the magnetic recording medium, the magnetic field generation means and the surface of the contact body are in close proximity to each other. Rotating at least one of the magnetic field generating means and the contact body around a substantially central portion of the magnetic recording medium to rotate the magnetic field generating means relative to the contact body. The magnetic field generating means has a magnetic core and a coil, a magnetic field is generated by energizing the coil by the current applying means, and the current applying means is set by the relative rotation. After allowed to at least one revolution, in a state where the rotation driving is continued, characterized in that it is a setting for decreasing the current value to be supplied to the coil. According to the magnetic transfer device as described above, it is possible to prevent deterioration of the transfer recording signal when the external magnetic field is removed by the magnetic head, and it is possible to perform uniform transfer recording on the entire surface of the magnetic recording medium.

Further, it is preferable that the current applying means gradually increases the current value of the coil for generating the magnetic field necessary for the transfer while performing the rotational driving. According to the magnetic transfer device as described above,
Even when starting to apply external magnetization by the magnetic head,
Since the deterioration of the transfer recording signal can be prevented, the uniform transfer recording on the entire surface of the magnetic recording medium becomes more reliable.

The magnetic field generating means preferably has a magnetic core of a ferromagnetic material and a permanent magnet.

The magnetic field generating means preferably has a magnetic core of a ferromagnetic material and a coil. According to the magnetic transfer device as described above, the external magnetic field can be applied and removed by controlling the current applied to the coil.

Next, in the method for manufacturing a magnetic recording medium of the present invention, a master information carrier having a ferromagnetic material corresponding to an information signal formed on the surface of a substrate is brought into close contact with a magnetic recording medium having a ferromagnetic layer. A method of manufacturing a magnetic recording medium, wherein a magnetic field is applied to a contact body by a magnetic field generating means to transfer an information signal of the master information carrier to the magnetic recording medium, the magnetic field generating means and the surface of the contact body. Are moved to a position close to each other, and at least one of the magnetic field generating means and the contact body is rotationally driven to relatively rotate the magnetic field generating means with respect to the contact body, thereby performing the relative rotation. After at least one rotation, the magnetic field generating means is separated from the contact body while continuing the rotation drive, and the transfer is finished. According to the method of manufacturing a magnetic recording medium as described above, it is possible to prevent the transfer recording signal from deteriorating in the separated phase of the magnetic head, and it is possible to perform uniform transfer recording on the entire surface of the magnetic recording medium.

In the method of manufacturing the magnetic recording medium,
The movement to the position where the magnetic field generating means and the surface of the contact body come close to each other is such that at least one of the magnetic field generating means and the contact body is rotationally driven with the substantially central portion of the magnetic recording medium as a rotation center. It is preferable that the magnetic field generating means is rotated while rotating relative to the contact body. According to the method for manufacturing a magnetic recording medium as described above,
Even when the magnetic head is approaching, the deterioration of the transfer recording signal can be prevented, so that the uniform transfer recording on the entire surface of the magnetic recording medium becomes more reliable.

Next, another method of manufacturing the magnetic recording medium of the present invention
In this method, a ferromagnetic material corresponding to the information signal is formed on the surface of the substrate.
Recording having a master information carrier and a ferromagnetic layer
The magnetic field generated by the magnetic field generation means
To apply the information signal of the master information carrier to the magnetic field.
A method for manufacturing a magnetic recording medium for transferring onto a recording medium, comprising:
Position where the magnetic field generating means and the surface of the contact body are close to each other
Of the magnetic field generating means and the contact body.
By rotating at least one of the magnetic field generating means,
It is relatively rotated with respect to the adhesion member, before Symbol magnetic field generating means has a magnetic core and a coil, a magnetic field is generated by energization of the coil, at least one rotation the relative rotation After that, in the state where the rotation drive is continued,
It is gradually decreased to a current value to be supplied to said coil, characterized in that finish the transcription. Of the magnetic recording medium as described above
According to the manufacturing method , it is possible to prevent the deterioration of the transfer recording signal when the external magnetic field is removed by the magnetic head,
Uniform transfer recording on the entire surface of the magnetic recording medium becomes possible.

Further, it is preferable that the current value of the coil for generating the magnetic field necessary for the transfer is applied while gradually increasing the current value while performing the rotational driving. According to the magnetic transfer device as described above, it is possible to prevent the transfer recording signal from deteriorating even when the application of the external magnetization is started by the magnetic head, so that the uniform transfer recording on the entire surface of the magnetic recording medium is more surely performed. Become.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 shows a magnetic transfer apparatus according to the present embodiment. 1 is a magnetic disk as a magnetic recording medium, 2 is a magnetic transfer master as a master information carrier, 2d is a contact surface with the magnetic disk 1 on the magnetic transfer master 2, and the contact surface 2d is shown in FIG. As shown in the drawing, grooves 2e radially provided from the center of the magnetic transfer master 2 are provided. 3 is a transfer magnetic head, 4 is a magnetic head arm, 5 is a magnetic head rotating shaft,
Reference numeral 17 is a magnetic head drive mechanism, and 18 is a control circuit.

Reference numeral 6 is a support base for supporting the magnetic disk 1, and a vent hole 7 for allowing gas to flow is provided in the center portion. 8 is a flow path for discharging and pressure-feeding the gas between the magnetic transfer master 2 and the magnetic disk 1, 9 is a gas discharge port for discharging the gas from the flow path 8, and 10 is connected to the gas discharge port. The suction pump 11 is an exhaust valve that controls the discharge of gas. Further, 12 is an air supply pump for pressure-feeding the gas to the flow path 8, and 13 is an air supply valve for controlling the air supply of the gas.

Here, the air supply pump 12 has 0.01 μm.
m air filter is provided so that foreign matter of 0.01 μm or more is not pumped into the passage 8. First, the drive mechanism of the transfer magnetic head 3 will be described. The transfer magnetic head 3 is attached to a magnetic head drive mechanism 17 via a magnetic head arm 4 and a magnetic head rotating shaft 5.

The magnetic head driving mechanism 17 raises and lowers the transfer magnetic head 3 relative to the magnetic disk 1 by rotating the transfer magnetic head 3 in parallel with the magnetic disk 1. And a retracting mechanism section including a linear stage and the like for retracting the transfer magnetic head 3 from the magnetic disk 1 (details not shown).

The magnetic head drive mechanism 17 includes a control circuit 18
And is freely driven and controlled by a command signal from the control circuit 18. The magnetic head drive mechanism is not limited to the above-mentioned configuration, and may have any configuration as long as the same operation can be performed.

Next, the steps of suction / pressure feeding of the magnetic transfer master will be described in detail with reference to FIGS.
First, the step of separating by pressure feeding will be described with reference to FIG. The magnetic head 3 and the magnetic head arm 4 shown in FIG.
The rotary shaft 5 and the magnetic transfer master 2 are driven by the magnetic head drive mechanism 17 in accordance with a signal from the control circuit 18.
After retreating from the upper part, the master transfer member 14 for magnetic transfer
Is closely attached to the magnetic transfer master 2. Thereafter, the suction flow path 15 provided in the magnetic transfer master transport member 14
The magnetic transfer master is adsorbed by discharging the gas from the.

Next, by operating the air supply pump 12 with the exhaust valve 11 closed and the air supply valve 13 open,
Gas is poured into the passage 8. Then, the air is pressure-fed upward to the ventilation hole 7 as shown by an arrow D in FIG. As a result, the air pressure-fed to the ventilation hole 7 is pressure-fed to the groove 2e. The air pressure-fed to the groove 2e spreads radially from the center of the magnetic transfer master 2 to the outer periphery through the groove 2e.

Then, it further escapes from the groove 2e to the atmosphere through the gap between the magnetic transfer master 2 and the magnetic disk 1. By this operation, the magnetic transfer master 2 that was in close contact with the magnetic disk 1 is slightly separated.

FIG. 4 shows the relationship between the elapsed time and the atmospheric pressure in the space between the magnetic transfer master 2 and the magnetic disk 1 (hereinafter referred to as space A). The air pressure in space A is 101.3 kpa from around 3 seconds
Then, the period in which the atmospheric pressure of about 130 kpa is maintained for about 1 second thereafter corresponds to the state in which the magnetic transfer master 2 and the magnetic disk 1 are separated from each other.

Next, the step of adhering by suction will be described with reference to FIG. Stop the air supply pump 12,
The air supply valve 13 is closed. Then, the exhaust valve 11 is opened and the suction pump 10 is operated. Then, as shown by the arrow E in FIG. 3, the gas in the vent hole 7 is discharged downward, so that the gas in the groove 2e, that is, the space A is also discharged.

As shown in FIG. 2, the groove 2e does not have a shape extending to the outermost circumference of the magnetic transfer master 2, so that the magnetic transfer master 2 and the magnetic disk 1 are formed at the outermost donut-shaped portion. Are in close contact with each other over the entire circumference, and the space A is in a sealed state. Its pressure will be lower than atmospheric pressure.

Therefore, the magnetic transfer master 2 is pressed against the magnetic disk 1 by the atmospheric pressure. Figure 4
The section where the atmospheric pressure of the space A is about 30 kpa corresponds to the above-mentioned close contact state.

Next, the magnetic transfer master 2 will be described in detail. FIG. 9 schematically shows a plane of an example of the magnetic transfer master 2. As shown in FIG. 9, one main surface of the magnetic transfer master 2, that is, the side that contacts the ferromagnetic thin film surface of the magnetic disk 1. A signal region 2a is formed substantially radially on the surface of the. 2 and 9 are schematic diagrams, and in reality, the signal region 2a in FIG.
Is formed on the contact surface in.

An enlarged view of a portion A surrounded by a dotted line in FIG. 9 is schematically shown in FIG. As shown in FIG. 10, the signal area 2
In a, a master information pattern is formed at a position corresponding to a digital information signal to be recorded on the magnetic disk 1, for example, preformat recording, by a magnetic portion made of a ferromagnetic thin film in a pattern shape corresponding to the information signal. .

In FIG. 10, the hatched portion is a magnetic portion made of a ferromagnetic thin film. The master information pattern shown in FIG. 10 is formed by sequentially arranging areas of the clock signal, the tracking servo signal, the address information signal, etc. in the track length direction. The master information pattern shown in FIG. 10 is an example,
Depending on the digital information signal recorded on the magnetic disk 1, the configuration, arrangement, etc. of the master information pattern will be appropriately determined.

For example, when a reference signal is first recorded on a magnetic film of a hard disk as in a hard disk drive and preformat recording such as a tracking servo signal is performed based on the reference signal, the master information medium according to the present invention. Pre-format recording such as tracking servo signals is performed on the magnetic head of the hard disk drive by pre-recording only the reference signal used for pre-format recording on the magnetic film of the hard disk by using the May be used.

A partial cross section of the region shown in FIGS. 9 and 10 is shown in FIG. As shown in FIG. 11, the magnetic transfer master 2 includes one main surface of a disk-shaped base 2b made of a non-magnetic material such as a Si substrate, a glass substrate, or a plastic substrate.
That is, on the surface on the side where the surface of the magnetic disk 1 contacts,
The recesses 2c are formed in a plurality of minute array pattern shapes corresponding to information signals, and the ferromagnetic film 16 serving as a magnetic part is embedded in the recesses 2c of the base 2b.

Here, as the ferromagnetic thin film 16, many kinds of magnetic materials can be used regardless of hard magnetic material, semi-hard magnetic material, and soft magnetic material, and a digital information signal is transferred to a magnetic recording medium. Anything that can be recorded is acceptable. For example, Fe, Co, an Fe-Co alloy, or the like can be used.

In order to generate a sufficient recording magnetic field regardless of the type of magnetic recording medium on which master information is recorded, it is generally better that the saturation magnetic flux density of the magnetic material is large. In particular, for a magnetic disk having a high coercive force exceeding 2000 Oersted or a flexible disk having a large magnetic layer thickness, sufficient recording may not be possible when the saturation magnetic flux density is 0.8 Tesla or less.
Generally, a magnetic material having a saturation magnetic flux density of 0.8 Tesla or more, preferably 1.0 Tesla or more is used.
The thickness of the ferromagnetic thin film 16 depends on the bit length, the saturation magnetization of the magnetic recording medium and the film thickness of the magnetic layer. For example, the bit length is about 1 μm and the saturation magnetization of the magnetic recording medium is about 500 emu / c.
c. When the thickness of the magnetic layer of the magnetic recording medium is about 20 nm, it may be about 50 nm to 500 nm.

In order to obtain a good recording signal quality in such a recording system, based on the arrangement pattern of the soft magnetic thin film or the semi-hard magnetic thin film as the ferromagnetic thin film provided in the magnetic transfer master, During preformat recording, it is desirable to excite this and uniformly magnetize it. Further, prior to signal recording using the magnetic transfer master 2, it is preferable to uniformly initially magnetize a magnetic recording medium such as a hard disk. desirable.

Next, the transfer magnetic head 3 will be described. FIG. 8 shows a sectional view in the circumferential direction of the magnetic disk 1 of the transfer magnetic head 3 and a distribution of magnetic force lines of the generated magnetic field. In the figure, 3a and 3b are a pair of magnetic cores, and a ferromagnetic material such as SS41 is used as the material.

Reference numeral 3c is a permanent magnet, which is made of a material having a high residual magnetic flux density such as a neodymium / iron / boron-based material.
3d is a gap and 3e is a magnetic force line of the generated magnetic field.
A portion of a region J surrounded by an ellipse with a dotted line in the figure is a horizontal magnetic field component used for transfer. On the other hand, the regions K and L are vertical magnetic field components that cause signal deterioration in the conventional example.

Next, a method of manufacturing the magnetic transfer master 2 will be described. That is, the magnetic transfer master used in the recording method of the present invention forms a resist film on the surface of a Si substrate, and exposes the resist film by a lithography technique using a laser beam or an electron beam such as a photolithography method. After development and patterning, etching is performed by dry etching or the like to form a fine concavo-convex shape corresponding to an information signal, and then a ferromagnetic thin film made of Co or the like is sputtered, vacuum deposited, ion plated, or CVD. It is possible to obtain a master for magnetic transfer having a magnetic portion corresponding to an information signal in a form in which the ferromagnetic thin film is embedded in the concave portion by a plating method, a plating method, or the like.

The method for forming the uneven shape on the surface of the magnetic transfer master is not limited to the above-mentioned method, and for example, a fine uneven shape is directly formed by using a laser, an electron beam or an ion beam. Alternatively, fine irregularities may be directly formed by machining.

Next, the procedure for transferring and recording the information signal corresponding to the pattern shape formed on the magnetic transfer master 2 on the magnetic disk 1 will be described in more detail. Figure 5
Shows the transfer process of the present embodiment. It demonstrates in order according to the process shown in the figure.

First, the initial magnetization of the magnetic disk 1 is performed.
The configurations of the magnetic head drive mechanism 17 and the control circuit 18 are similar to those of the transfer magnetic head 3. As shown in FIG. 6, in the present embodiment, the gap portion of the magnetic head 103 for initial magnetization (having the same configuration as the magnetic head for transfer described later, but the polarity of the permanent magnet is opposite) is set to 0. The state is close to a distance of 3 mm (proximity to magnetic head for initial magnetization).

Next, the magnetic head drive mechanism 17 is driven by a signal from the control circuit 18 in the direction of arrow A in FIG. By rotating the magnetic head 103 by 360 degrees or more, for example, 450 degrees, the magnetization direction of the magnetic disk 1 is preliminarily set to one direction as shown by the arrow in FIG. 12 (initial magnetization). When the initial magnetization is completed, the initial magnetization magnetic head 103 is separated from the magnetic disk 1 while maintaining the rotation (separation of the initial magnetization magnetic head).

Next, by the method described above, the magnetic transfer master 2 and the magnetic disk 1 are brought into close contact with each other in a state where the magnetic transfer master 2 is positioned and superposed on the magnetic disk 1. Further, the transfer magnetic head 3 is moved in the direction of arrow B in FIG. 1 by the magnetic head drive mechanism 17, and the gap 3d of the transfer magnetic head 3 is moved to the magnetic disk 1.
Close to a distance of 1.5 mm (proximity to the transfer magnetic head).

Then, the transfer magnetic head 3 is arranged in parallel with the magnetic disk 1 with the center of the magnetic disk 1 as the center.
Is rotated at a speed of 60 rotations / min by the magnetic head drive mechanism 17 in the direction of arrow A in FIG. By this operation, a magnetic field is applied in the direction opposite to the initial magnetization.

FIG. 14 shows the state of the magnetization process. As shown in FIG. 14, the magnetic transfer master 2 is in a state of being in close contact with the magnetic transfer master 2.
By applying a magnetic field from the outside to magnetize the magnetic portion 16, an information signal can be recorded in the ferromagnetic layer 1c of the magnetic disk 1. That is, by using the magnetic transfer master 2 configured by forming the magnetic portion 16 made of a ferromagnetic thin film on the non-magnetic substrate 2b in an array pattern shape corresponding to a predetermined information signal, the magnetization corresponding to the information signal is obtained. The pattern can be magnetically transferred and recorded on the magnetic disk 1. The arrow shown in FIG. 13 indicates the direction of the magnetic field of the magnetization pattern transferred and recorded on the magnetic disk 1 at this time (transfer).

Here, the operation at the time of transfer will be described in more detail. Rotational phase of the transfer magnetic head 3 during transfer, rotation speed of the transfer magnetic head 3, and transfer magnetic head 3
FIG. 7 shows the relationship between the distance between the gap 3d and the surface of the magnetic disk 1.

The transfer is completed when the transfer magnetic head 3 rotates 360 degrees or more, but the transfer magnetic head 3 continues to rotate at 60 rpm. In the example of this figure, when the rotational phase of the transfer magnetic head 3 reaches 450 degrees, it moves in the direction of arrow C in FIG. 1, the transfer magnetic head 3 starts to separate from the magnetic disk 1, and the rotational phase changes. When it reaches 540 degrees, the separation is completed. During this separating operation, the rotating operation of the transfer magnetic head 3 continues.

The separation distance at this time is 3 mm in the present embodiment. Regarding the operation during initial magnetization,
It is the same except that the distance of the magnetic head to the magnetic disk 1 is different.

After that, the transfer master 2 is separated by the method described above. According to the present embodiment, a signal recorded on the magnetic disk 1 is reproduced by using a floating magnetic head (having a magnetoresistive effect element) and a spin stand device used in an actual magnetic disk device. 21 and FIG.

FIG. 21 shows the rotational phase of the magnetic disk 1 and the peak value of the reproduction signal voltage. 22 corresponds to FIG.
The reproduced waveform in the separated phase of the transfer magnetic head 3 is shown. As can be seen from FIG. 22, in the reproduced waveform, the voltages v1 and v2 are substantially equal to each other.
No large reduction in peak level as seen in No. 5 has occurred. That is, it can be seen that the deterioration of the reproduction signal can be prevented by separating the transfer magnetic head 3 while maintaining the rotation operation. As a result, it is possible to suppress variations in the amplitude of the reproduced waveform over the entire rotation phase. That is, according to the present embodiment, it can be said that uniform transfer recording can be realized on the entire surface of the magnetic recording medium.

A schematic diagram showing a state of magnetization remaining in the magnetic layer of the magnetic disk 1 in this state and a schematic diagram of a reproduced signal waveform when a corresponding ring head is used,
16 (a) and 16 (b), respectively. Here, the direction of the arrow indicates the direction of the magnetic field, and the length indicates the strength of the magnetic field. A ring head (not shown) converts a change in magnetic flux intersecting the gap into an electric current. Therefore, FIG.
By scanning in proximity to the magnetic disk 1 magnetized as shown in (a), the leakage magnetic flux from the magnetic disk 1 is detected, and a reproduction signal waveform as shown in FIG. 16 (b) is obtained.

Here, the difference between the conventional example and the external magnetic field application state when the magnetic head 3 of this embodiment is separated is described, and the reason why the peak level of the reproduced signal waveform does not decrease in the embodiment of the present invention will be described. To do. In FIG. 15, the line segment FF indicates the approximate height of the contact surface between the transfer master 2 and the disc 1.

FIG. 18 shows the history of the magnetic field applied to the point G on the line segment FF when the magnetic head 3 moves rightward in the figure. The horizontal axis of FIG. 18 represents the magnetic field strength component horizontal to the transfer master 2, and the vertical axis represents the magnetic field strength component vertical to the transfer master 2.

The magnetic field strength in the horizontal direction is positive for the magnetic field directed to the right in the figure, and the magnetic field strength in the vertical direction is positive for the magnetic field directed in the upward direction in the figure. The curve shown by the solid line here is the history of the magnetic field at point G when the magnetic head 3 passes during transfer.

The history of the magnetic field at point G shown in FIG. 18 will be described in comparison with FIG. The point a in FIG. 18 corresponds to the case where the magnetic head 3 is at a position sufficiently separated from the point G. The vertical magnetic field increases as it goes from the point a to the point b, and becomes the maximum at the point b. The vertical magnetic field becomes smaller and the horizontal magnetic field becomes larger as it goes from the point b to the point c, and becomes maximum at the point c. This corresponds to passing through the point G in the order of the vertical magnetic field L and the horizontal magnetic field J. That is, as the vertical magnetic field L approaches the G point, the vertical magnetic field at the G point increases, and the vertical magnetic field L from the G point increases.
And the horizontal magnetic field J approaches the point G, the horizontal magnetic field increases.

Further, as proceeding from point c to point d,
As the horizontal magnetic field becomes smaller, the vertical magnetic field becomes larger in the negative direction and becomes maximum at point d. When reaching the point a through the point d, both the vertical magnetic field and the horizontal magnetic field become zero.
This corresponds to passing through the point G in the order of the horizontal magnetic field J and the vertical magnetic field K, and each magnetic field is zero at the point a where the magnetic head is sufficiently far from the point G. That is, as the horizontal magnetic field J moves away from the G point, the horizontal magnetic field at the G point decreases, and as the vertical magnetic field K approaches the G point, the vertical magnetic field at the G point increases.

The broken line in FIG. 18 is a comparative example showing the history of the magnetic fields applied to the points H and I when the magnetic head 3 is vertically separated in FIG. When the magnetic head 3 is separated in the vertical direction, points H and I are positions where the recording signal level drops significantly. Points b and d correspond to the magnetic fields at points I and H, respectively, when the magnetic head is at the starting point position. The horizontal magnetic field reaches its maximum value as the magnetic head 3 moves away from the transfer master 2, but this maximum value is smaller than the trajectory of the solid line. Further, in the solid line, the vertical magnetic field is zero at the point where the horizontal magnetic field has the maximum value, but in the trajectory of the broken line, a considerable amount of vertical magnetic field is applied.

In this way, when the magnetic head 3 passes and when it is separated vertically, the transfer master 2
The history of the magnetic field applied to the magnetic recording medium is significantly different, and this difference is the cause of the deterioration of the recording signal only in the separated phase of the magnetic head 3.

A schematic diagram of the magnetized state of the magnetic layer in the separated phase of the magnetic head 3 of the magnetic disk 1 in the conventional example, and a schematic diagram of the signal waveform reproduced by using the corresponding magnetic head mounted in the actual hard disk drive, Figure 20
20A and 20B, respectively. Similar to FIG. 16, the direction of the arrow indicates the direction of the magnetic field, and the length indicates the strength of the magnetic field. In this way, the strength of the magnetization is partially weakened, so that the reproduction signal voltage is reduced correspondingly.

In FIG. 19, the relative velocity between the magnetic head 3 and the transfer master 2 at the time of transfer, during the separation operation of the magnetic head 3 in the conventional example, and during the separation operation of the magnetic head 3 according to the embodiment of the present invention is represented by a velocity vector. Is shown as. S1 in the figure
Represents the velocity vector during transfer, S2 represents the velocity vector during the separating operation of the magnetic head 3 in the conventional example, and S3 represents the velocity vector during the separating operation of the magnetic head 3 in the embodiment of the present invention.

As described above, the relative speed between the magnetic head 3 and the transfer master 2 during the separating operation of the magnetic head 3 in the embodiment of the present invention is the rotating operation even during the separating operation of the magnetic head 3. It is closer to the velocity vector at the time of transfer as compared with the conventional example. Therefore, until the magnetic field applied from the magnetic head 3 to the transfer master becomes sufficiently small, the shape similar to the history of the magnetic field strength indicated by the solid line in FIG. 18 is maintained. As a result, the demagnetization of the recording signal generated at the time of separation in the conventional example is significantly alleviated.

As described above, according to the present embodiment, it is possible to obtain a great effect that good transfer can be realized over the entire surface of the magnetic disk 1 by replacing a part of the transfer process with respect to the conventional method.

Although the magnetic head 3 for transfer is rotationally driven in the present embodiment, the same effect can be obtained by rotationally driving the magnetic disk 1 side. That is, the transfer magnetic head 3 may rotate relative to the magnetic disk 1 side, and both the transfer magnetic head 3 and the magnetic disk 1 side may be rotationally driven.

Further, in the present embodiment, the transfer magnetic head 3 has been described as being composed of a magnetic core and a permanent magnet, but it is sufficient if an external magnetic field similar to that shown in FIG. You may use the electromagnet etc. which consist of a core and a coil. Although detailed description is omitted here, the same operation is performed for the operation at the initial magnetization. In the present embodiment, the case where the magnetic recording medium is an in-plane recording medium has been described as an example, but the same effect can be obtained when the present magnetic transfer device is used for transfer to a perpendicular recording medium.

(Second Embodiment) Next, another embodiment of the present invention will be described. The description of the same contents as those in the first embodiment will be omitted. In the first embodiment, the purpose is to solve the deterioration of the signal at the separated position of the transfer magnetic head 3. However, even when the transfer magnetic head 3 is close to the transfer condition, for example, the transfer magnetic head 3 is used. However, if the recording signal is not completely overwritten when passing through the proximity position again, the signal may be deteriorated even at the proximity position.

Therefore, in the first embodiment, the step of separating the transfer magnetic head 3 simultaneously with the rotating operation is performed only when the transfer magnetic head 3 is separated. According to the steps shown, even when the transfer magnetic head 3 performs the approaching operation, the approaching operation of the transfer magnetic head 3 is performed simultaneously with the rotating operation as in the separating operation.

FIG. 24 shows the relationship between the rotational phase of the transfer magnetic head 3 during transfer, the rotational speed of the transfer magnetic head 3 and the distance between the gap 3d of the transfer magnetic head 3 and the surface of the magnetic disk 1. There is. As shown in the figure, when the distance between the gap 3d of the transfer magnetic head 3 and the surface of the magnetic disk 1 approaches from 3 mm to 1.5 mm, and when the operation moves away from 1.5 mm to 3 mm. In both cases, the magnetic head is rotating at 60 rpm.

By adopting such a process, more reliable signal recording can be performed under a wide range of transfer conditions.

(Third Embodiment) Next, the third embodiment of the present invention will be described in detail. The description of the same contents as those in the first embodiment will be omitted. 25 and 26 show a magnetic transfer device according to the present embodiment. FIG. 29
3A shows a sectional view in the circumferential direction of the magnetic disk 1 of the magnetic head 203 in the present embodiment and a magnetic force line distribution of a generated magnetic field.

In the figure, 203a and 203b are magnetic cores made of a pair of ferromagnetic materials, 203c is a coil, 203d is a gap, and 203e is a magnetic force line. In the first and second embodiments, the external magnetic field is applied and removed by moving the magnetic heads close to and away from each other. On the other hand, in the present embodiment, the external magnetic field is applied and removed by controlling the current flowing through the coil 203c.

A procedure for transferring and recording the information signal corresponding to the pattern shape formed on the magnetic transfer master 2 on the magnetic disk will be described with reference to FIGS. 25 to 27. First, with the magnetic disk 1 mounted on the support 6 as shown in FIG.
Is brought close to the magnetic disk 1 to a distance of, for example, 0.3 mm (close to the magnetic head). In that state, the magnetic head 20
A current of 20 A, for example, is applied to the coil 203c of No. 3,
Generate a magnetic field.

Next, by rotating the rotary shaft 5 in the direction of arrow A in FIG. 26 about the center of the magnetic disk 1, the magnetic head 203 is rotated 360 degrees or more, for example 450 degrees. As shown by the arrow in FIG. 12, the magnetization direction of the magnetic disk 1 is previously set to one direction (initial magnetization).

Next, while the rotation of the magnetic head 203 is maintained, the value of the current passing through the coil 203c is gradually reduced. After that, the magnetic head 203 is once separated from the disk 1.

Next, as shown in FIG. 25, the magnetic transfer master 2 and the magnetic disk 1 are brought into close contact with each other with the magnetic transfer master 2 positioned and superposed on the magnetic disk 1. In this state, the gap 203d of the magnetic head 203 is brought close to the magnetic disk 1 to a distance of, for example, 1.5 mm (close to the magnetic head). After that, the coil 203c is again provided with, for example, 2 in the direction opposite to that in the initial magnetization.
A current of 0 A is passed through the magnetic head 203 in parallel with the magnetic disk 1 with the center of the magnetic disk 1 as the center.
By rotating in the direction of the middle arrow A, a magnetic field is applied in the direction opposite to the initial magnetization and transfer is performed (transfer).

Here, the operation at the time of transfer will be described in more detail. FIG. 28 is a diagram showing the relationship between the magnetic head rotation phase at the time of transfer, the magnetic head rotation speed, and the value of the current applied to the coil of the magnetic head in the third embodiment.
The transfer is completed by rotating the magnetic head 203 by 360 degrees or more, but the coil 20 is rotated at 450 degrees while the magnetic head 203 is still rotated.
The value of the current passing through 3c is gradually reduced.

More specifically, the coil current is reduced from 20 A to 0 A as the rotation phase changes from 450 degrees to 540 degrees. During this time, the magnetic head 203 continues to rotate at 60 rpm. In this embodiment, the magnetic head 2
Since the current value is gradually reduced while rotating 03, the transfer is completed without separating the magnetic head 203.

The operation at the time of initial magnetization is the same except that the distance of the magnetic head to the magnetic disk 1 is different. With such a process, the first embodiment
The same effect as can be obtained. By thus using the electromagnet as the magnetic head, the magnetic head for initial magnetization and the magnetic head for transfer can be shared, and the magnetic field can be applied and removed by controlling the current, so that the degree of freedom in designing the device is improved. There is an advantage.

In this embodiment, the case where the magnetic recording medium is an in-plane recording medium has been described as an example, but the same effect can be obtained when the present magnetic transfer device is used for transfer to a perpendicular recording medium. .

(Fourth Embodiment) Next, another embodiment of the present invention will be described. The description of the same contents as in the third embodiment will be omitted. In the third embodiment, the purpose is to solve the deterioration of the signal at the cutoff position of the magnetic head 203 to the coil 203c. However, even when the current is applied to the coil, the transfer condition, that is, the magnetic head 2 is used.
In No. 03, when the overwriting is not perfect when passing the current application position again, the signal may be deteriorated at the current application position. Therefore, in the third embodiment,
The purpose of the present invention is to prevent the deterioration of the signal at the current cutoff position by gradually reducing the current of the coil 203c of the magnetic head 203. When the current is cut off, the operation is performed simultaneously with the rotation operation. FIG. 31 shows the relationship between the rotational phase of the magnetic head 203 during transfer, the rotational speed of the magnetic head 203, and the value of the current applied to the coil 203e of the magnetic head 203.

As shown in the figure, when the current is applied, the coil current is gradually increased from 0 A to 20 A while the magnetic head is rotating at 60 rpm. When the current is cut off, the coil current is gradually reduced from 20 A to 0 A while the magnetic head continues to rotate at 60 rpm.
In this embodiment, while rotating the magnetic head 203,
Since the current value is applied and cut off, the position of the magnetic head 203 in the height direction is fixed from the start to the end of the transfer.

With such a process, more reliable signal recording can be performed under a wide range of transfer conditions. The initial magnetization is the same except that the position of the magnetic head with respect to the magnetic disk is different.

[0097]

As described above, according to the present invention, it is possible to prevent the deterioration of the transfer recording signal due to the influence of the vertical magnetic flux existing under the gap of the magnetic head used for generating the external magnetic field in the separation phase of the magnetic head. Therefore, uniform transfer recording can be performed on the entire surface of the magnetic recording medium.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a magnetic transfer device according to a first embodiment during transfer.

FIG. 2 is a diagram showing a contact surface 3 with a magnetic disk 1 in a magnetic transfer master 2 according to the first embodiment.

FIG. 3 is a cross-sectional view showing a state where the master carrier of the magnetic transfer device according to the first embodiment is suctioned / separated.

FIG. 4 is a diagram showing a relationship between time and pressure in space A according to the first embodiment.

FIG. 5 is a diagram showing a transfer process in the first embodiment.

FIG. 6 is a diagram showing a method of initial magnetization of a magnetic disk according to the first embodiment.

FIG. 7 is a diagram showing the relationship between the magnetic head rotation phase at the time of transfer, the magnetic head rotation speed, and the distance between the magnetic head gap and the magnetic disk surface in the first embodiment.

FIG. 8 is a sectional view of the magnetic head according to the first embodiment.

FIG. 9 is a diagram showing a signal area on a master information carrier according to the first embodiment.

FIG. 10 is a view of FIG. 9A in the first embodiment.
Figure showing the details

FIG. 11 is a detailed cross-sectional view of a signal area on the master information carrier according to the first embodiment.

FIG. 12 is a diagram showing an initial magnetization state of the magnetic disk according to the first embodiment.

FIG. 13 is a diagram showing a direction in which a transfer magnetic field is applied to the magnetic disk according to the first embodiment.

FIG. 14 is a diagram showing magnetization states of a master information carrier and a magnetic disk at the time of transfer in the first embodiment.

FIG. 15 is a sectional view of the magnetic head according to the first embodiment.

FIG. 16 is a schematic diagram of a magnetic disk cross section in a good recording state and a diagram showing a corresponding reproduction signal.

FIG. 17 is a sectional view of the magnetic head according to the first embodiment.

FIG. 18 is a diagram schematically showing a transfer magnetic field and a history of the magnetic field when the magnetic head is separated.

FIG. 19 shows a magnetic head 3 and a transfer master 2.
Diagram showing the relative velocity of each as a velocity vector

FIG. 20 is a schematic view of a cross section of a magnetic disk in which a part of a recording signal is demagnetized and a diagram showing a corresponding reproduction signal.

FIG. 21 is a diagram showing a relationship between a disk rotation phase and a reproduction signal peak value according to the first embodiment.

FIG. 22 is a diagram showing a reproduction signal waveform at the transfer magnetic head separation start position in the first embodiment.

FIG. 23 is a diagram showing a transfer process in the second embodiment.

FIG. 24 is a diagram showing the relationship between the magnetic head rotation phase at the time of transfer, the magnetic head rotation speed, and the distance between the magnetic head gap and the magnetic disk surface in the second embodiment.

FIG. 25 is a sectional view of the magnetic transfer device according to the third embodiment at the time of transfer.

FIG. 26 is a sectional view of the magnetic transfer device according to the third embodiment at the time of initial magnetization.

FIG. 27 is a diagram showing a transfer process in the third embodiment.

FIG. 28 is a diagram showing the relationship between the magnetic head rotation phase at the time of transfer, the magnetic head rotation speed, and the current value applied to the coil of the magnetic head in the third embodiment.

FIG. 29 is a sectional view of a magnetic head according to the third embodiment.

FIG. 30 is a diagram showing a transfer process according to the fourth embodiment.

FIG. 31 is a diagram showing the relationship between the magnetic head rotation phase at the time of transfer, the magnetic head rotation speed, and the current applied to the coil of the magnetic head in the fourth embodiment.

FIG. 32 is a diagram showing a transfer process in a conventional example.

FIG. 33 is a diagram showing the relationship between the magnetic head rotation phase during transfer, the magnetic head rotation speed, and the distance between the magnetic head gap and the magnetic disk surface in the conventional example.

FIG. 34 is a diagram showing a relationship between a disk rotation phase and a reproduction signal peak value in a conventional example.

FIG. 35 is a diagram showing a reproduction signal waveform at a transfer magnetic head separation start position in a conventional example.

[Explanation of symbols]

1 magnetic disk 2 Master information carrier 3 Magnetic head for transfer 4 Magnetic head arm 5 rotation axes 6 support 7 vents 8 channels 9 gas outlet 10 Suction pump 11 Exhaust valve 12 Air supply pump 13 Air supply valve 17 Magnetic head drive mechanism 18 Control circuit

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hideyuki Hashi, Inventor Hideyuki Hashi, 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. the inner (72) inventor Tatsuro Ishida Osaka Prefecture Kadoma Oaza Kadoma 1006 address Matsushita unit intra-industry Co., Ltd. (56) reference JP 2001-28124 (JP, a) (58 ) investigated the field (Int.Cl. ⁷ , DB name) G11B 5/62-5/86

Claims (11)

(57) [Claims] 1. A magnetic field is applied by magnetic field generating means to a close contact body in which a master information carrier having a ferromagnetic body corresponding to an information signal formed on the surface of a substrate and a magnetic recording medium having a ferromagnetic layer are in close contact with each other. In the magnetic transfer device for transferring the information signal of the master information carrier to the magnetic recording medium, the distance between the magnetic field generation means and the contact body while relatively rotating the magnetic field generation means and the contact body. a drive means for adjusting the setting of said driving means, said contact member and said magnetic field generating means
The magnetic recording by moving it to a position close to the surface of
With the substantial center of the medium as the center of rotation,
And rotating at least one of the contact members,
The magnetic field generating means is rotated relative to the contact body.
The magnetic field generating means while continuing the rotational drive.
A magnetic transfer device characterized in that the magnetic transfer device is set so as to be separated from the contact body . 2. A ferromagnet corresponding to an information signal on the surface of a substrate.
Has a master information carrier with a body formed and a ferromagnetic layer
As a magnetic field generating means for an adherent body in close contact with a magnetic recording medium
A magnetic field is applied to generate the information signal of the master information carrier.
In the magnetic transfer device for transferring onto the magnetic recording medium, the magnetic field generating means and the contact body are not rotated relative to each other.
However, the distance between the magnetic field generating means and the contact body is adjusted.
The driving means is set such that the driving means is moved to a position where the magnetic field generating means and the surface of the contact body come close to each other, and the magnetic field generating means is set with a substantially central portion of the magnetic recording medium as a rotation center. And rotationally driving at least one of the contact members,
The magnetic field generation means is rotated relative to the contact body, and after the relative rotation is rotated at least once, the magnetic field generation means is separated from the contact body while continuing the rotation drive. A magnetic transfer device characterized by being set. 3. The movement to a position where the magnetic field generating means and the surface of the close contact body come close to each other is such that at least one of the magnetic field generating means and the close contact body is rotated about a substantially central portion of the magnetic recording medium. 3. The magnetic transfer apparatus according to claim 1 or 2, wherein the magnetic field generating means is rotationally driven to rotate the magnetic field generating means relative to the contact body. 4. A ferromagnet corresponding to an information signal on the surface of a substrate.
Has a master information carrier with a body formed and a ferromagnetic layer
As a magnetic field generating means for an adherent body in close contact with a magnetic recording medium
A magnetic field is applied to generate the information signal of the master information carrier.
In the magnetic transfer device for transferring the magnetic recording medium, in a state where the front Symbol magnetic field generating means and the surface of the contact body is close, as the center of rotation substantially the center portion of said magnetic recording medium, the magnetic field generating means and the contact At least one of the bodies can be rotationally driven to rotate the magnetic field generating means relative to the contact body, the magnetic field generating means having a magnetic core and a coil, and A magnetic field is generated by the energization of the coil by the applying unit, and the current applying unit is set by rotating the relative rotation at least once, and then continuing the rotational driving,
This is a setting for decreasing the current value to be supplied to said coil
And a magnetic transfer device. 5. The current applying unit applies the current value of the coil for generating a magnetic field necessary for the transfer by gradually increasing the current value while performing the rotational driving. Magnetic transfer device. Wherein said magnetic field generating means, the magnetic transfer apparatus according to claim 1 or 2 has a magnetic core and a permanent magnet of ferromagnetic material. Wherein said magnetic field generating means, the magnetic transfer apparatus according to claim 1 or 2 has a magnetic core and a coil of ferromagnetic material. 8. A magnetic field is applied by a magnetic field generating means to a close contact body in which a master information carrier having a ferromagnetic material corresponding to an information signal formed on the surface of a substrate and a magnetic recording medium having a ferromagnetic layer are in close contact with each other. A method of manufacturing a magnetic recording medium for transferring an information signal of the master information carrier to the magnetic recording medium, the magnetic field generating means being moved to a position where the surface of the contact body is close to the magnetic field generating means. And rotating at least one of the contact bodies to rotate the magnetic field generating means relative to the contact body, and rotating the relative rotation at least once, and then continuing the rotation drive. However, the method of manufacturing a magnetic recording medium, characterized in that the magnetic field generating means is separated from the contact body to finish the transfer. 9. The movement to a position where the magnetic field generating means and the surface of the contact body come close to each other is such that at least one of the magnetic field generating means and the contact body is rotated about a substantially central portion of the magnetic recording medium. 9. The method of manufacturing a magnetic recording medium according to claim 8, wherein the magnetic field generating means is rotated while rotating the magnetic field generating means relative to the contact body. 10. A strong magnetic field corresponding to an information signal on the surface of a substrate.
It has a master information carrier on which a material is formed and a ferromagnetic layer.
The magnetic field generating means
By applying a magnetic field by the information signal of the master information carrier
Of manufacturing magnetic recording medium for transferring magnetic field to the magnetic recording medium
A is a position where said magnetic field generating means and the surface of the contact body comes close
Of the magnetic field generating means and the contact body.
By rotating at least one of the magnetic field generating means,
The magnetic field generating means has a magnetic core and a coil, and the magnetic field is generated by energizing the coil to rotate the relative rotation at least once. After that, the magnetic recording medium manufacturing method is characterized in that the current value applied to the coil is gradually reduced and the transfer is finished in a state where the rotational drive is continued. 11. The method of manufacturing a magnetic recording medium according to claim 10, wherein a current value of the coil for generating a magnetic field required for the transfer is applied while gradually increasing the current value while performing the rotational driving. .