JPH07282430A - Magnetic recording medium for transfer and transfer method - Google Patents

Abstract

PURPOSE:To lessen the degaussing of mother tapes and to obtain good transfer output by providing magnetic columns with magnetic films grown diagonally with the film plane. CONSTITUTION:The mother tape M and the blank, tape B are mounted in such a manner that the magnetic metallic film 9 of the tape M and the magnetic metallic film 6 of the tape B are so superposed on as to contact with each other. Bias magnetic fields are impressed on the tape M from its base side in a direction perpendicular to its base plane by a ring type magnetic head, by which the recording information signals of the tape M are transferred on the tape B. Transfer at a high speed is thus made possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer technique used for recording an information signal of a mother tape on a blank tape.

[0002]

BACKGROUND OF THE INVENTION Conventionally, an information signal of a first magnetic recording medium (also called a mother tape or a master tape) is recorded at a high speed on a second magnetic recording medium (also called a blank tape or a slave tape). A magnetic transfer technique has been proposed as a means for achieving this. For example, Japanese Patent Laid-Open No. 4-16
As disclosed in Japanese Patent No. 3722, an external bias magnetic field is applied to a mother tape of a metal vapor deposition thin film type mother tape and a metal vapor deposition thin film type blank tape in such a manner that their columns are tilted in opposite directions. In the magnetic transfer method of transferring the recording magnetization of No. 1 to the blank tape, the external bias magnetic field is 110 ° ± from the in-plane direction of the mother tape for which the easy axis of magnetization is selected to be 20 ° ± 15 ° from the in-plane direction. A magnetic transfer method has been proposed which is characterized by applying in the direction of 15 °.

According to such a magnetic transfer system, the magnetic transfer efficiency is improved, demagnetization is small, and
It is said that the mother tape does not require a large coercive force and a good transfer output can be obtained.

[0004]

DISCLOSURE OF THE INVENTION Incidentally, since the transfer is not performed while the mother tape or the blank tape is stationary, that is, because the transfer is performed while the mother tape or the blank tape is running. It has become clear that the above-mentioned proposed technology is not sufficient.

That is, in view of the fact that the transfer is carried out under the running condition of the tape, as a result of earnestly studying such a point, when the easy axis of magnetization of the mother tape or blank tape has a specific relationship, It has been found that there is little problem of demagnetization of the mother tape and that good transfer output can be obtained. The present invention has been achieved on the basis of such knowledge, and an object of the present invention is to provide a technique for copying an information signal in which the problem of demagnetization of a mother tape is small and good transfer output can be obtained. The purpose is to do.

An object of the present invention is a second magnetic recording medium to which an information signal recorded on the first magnetic recording medium is transferred, wherein the first magnetic recording medium has a plane of easy magnetization. A magnetic recording medium for transfer, characterized in that it has an inward magnetic film, and the second magnetic recording medium has a magnetic film in which a magnetic column grows obliquely with respect to the film surface. To be done.

A method of transferring the information signal recorded on the first magnetic recording medium to the second magnetic recording medium, wherein the first magnetic recording medium has a magnetic axis whose easy axis is in the in-plane direction. The second magnetic recording medium has a film, and the second magnetic recording medium has a magnetic film in which a magnetic column grows obliquely with respect to the film surface. The first magnetic recording medium and the second magnetic recording medium The magnetic recording layers are made to run so that the magnetic films are located inside each other, and a bias magnetic field is applied from the side of the first magnetic recording medium.

Then, the first magnetic recording medium and the second magnetic recording medium are superposed such that the magnetic films of the first magnetic recording medium and the second magnetic recording medium are located inside each other, and The bias magnetic field is applied from the side of the magnetic recording medium, but it is preferable that the bias magnetic field is applied in the direction perpendicular to the first magnetic recording medium. Even if the bias magnetic field is applied in the direction perpendicular to the surface of the first magnetic recording medium by the ring-type magnetic head, the second magnetic recording medium is running, so the applied bias magnetic field is It is along the direction of the easy axis of magnetization of the traveling second magnetic recording medium. That is, considering the column direction and the traveling direction in the magnetic film of the second magnetic recording medium, the second magnetic field in which the bias magnetic field applied in the vertical direction travels.
The magnetic recording medium is along the direction of the easy axis of magnetization.

The present invention will be described in more detail below. The support used in the magnetic recording medium (first magnetic recording medium and second magnetic recording medium) of the present invention is a non-magnetic one, and such a support may be polyester such as PET, polyamide, polyimide or poly. Olefin resins such as sulfone, polycarbonate and polypropylene, cellulose resins, organic materials such as vinyl chloride resins, ceramics such as glass, and other metal materials such as aluminum alloys are used. An undercoat layer for improving the adhesion of the magnetic layer (magnetic thin film) is provided on the surface of the support. That is, by appropriately roughening the surface roughness, for example, the adhesion of the magnetic thin film formed by the oblique deposition method is improved, and the surface roughness of the metal magnetic thin film surface is moderated to improve the running property. Therefore, for example, the thickness containing particles such as SiO ₂ is 0.005 to
The undercoat layer is formed by providing a 0.1 μm coating film.

Regarding the second magnetic recording medium (blank tape), a metal magnetic thin film is provided on one surface side of the support as described above by an oblique vapor deposition apparatus as shown in FIG.
In FIG. 1, 1 is a non-magnetic support, 2 is a cooling can roll, 3 is a crucible, 4 is a magnetic metal, and 5 is an electron gun. Examples of the material of the magnetic particles forming the metal magnetic thin film include metals such as Fe, Co and Ni, as well as Co—Ni alloys and C
o-Pt alloy, Co-Ni-Pt alloy, Fe-Co alloy, Fe-Ni alloy, Fe-Co-Ni alloy, Fe-C
An o-B alloy, a Co-Ni-Fe-B alloy, a Co-Cr alloy, or those containing a metal such as Al is used. Incidentally, it is preferable that an oxidizing gas is supplied when the metal magnetic thin film is formed, and a protective layer made of an oxide film is formed on the surface layer of the metal magnetic thin film.

The blank tape having the magnetic film obtained by the magnetic column thus obtained grown obliquely with respect to the film surface is, as shown in FIG. 2, an oblique axis in which the easy axis of magnetization is inclined with respect to the film surface. It is a thing. In FIG. 2, B is a blank tape, and 6 is a metal magnetic thin film made of a diagonal vapor deposition film. Regarding the first magnetic recording medium (mother tape), a metal magnet having an easy axis of magnetization in the in-plane direction (longitudinal direction) is used on one surface side of the support as described above using the sputtering apparatus as shown in FIG. A thin film is provided. In FIG. 3, 1 is a non-magnetic support, 7 ₁ and 7 ₂ are heating rolls, and 8 ₁ and 8 ₂ are targets. As the magnetic material (target) constituting the metal magnetic thin film, for example, in addition to metals such as Fe, Co and Ni, Co—Ni alloy, Co—Pt alloy, Co—Ni—P
t alloy, Fe-Co alloy, Fe-Ni alloy, Fe-Co
-Ni alloy, Fe-Co-B alloy, Co-Ni-Fe-
B alloy, Co-Cr alloy, Co-Cr-Pt alloy, Co-Cr-Ta alloy, or the like is used.

The mother tape having the metal magnetic thin film having the easy axis of magnetization in the in-plane direction is shown in FIG.
As shown in. In FIG. 4, M is a mother tape, 1 is a support, and 9 is a horizontal magnetized film. An information signal is recorded on this mother tape M by an ordinary means. Then, the recording information signal of the metal thin film type mother tape M having the horizontally magnetized film is copied by magnetic transfer to the blank tape B having the metal magnetic film in which the magnetic column grows obliquely with respect to the film surface.

This copying is performed as shown in FIGS. First, as shown in FIG. 5, the mother tape M
The metal magnetic film 9 and the metal magnetic film 6 of the blank tape B are superposed so as to be in contact with each other, and the mother tape M and the blank tape B are mounted on the magnetic transfer device of FIG. And
A bias magnetic field is applied from the support 1 side of the mother tape M in a direction perpendicular to the support 1 surface by the ring-type magnetic head 11 to transfer the recording information signal of the mother tape M to the blank tape B. In FIG. 6, 12a is a mother tape M
Supply reel, 12b is a take-up reel for the mother tape M, 13a is a supply reel for the blank tape B, 13b
Is a reel on the winding side of the blank tape B, 14 and 15 are guide rollers, and 16 is a transfer drum.

When the information signal is copied as described above, since it is a transfer, the transfer can be performed at a high speed.
Since the blank tape B is running at the time of this transfer, the bias magnetic field applied in the direction perpendicular to the support 1 surface of the mother tape M is applied to the blank tape B in the direction of the easy axis of magnetization (magnetic field). The magnetic field is applied along the column direction), and for the running mother tape M, the bias magnetic field is in the hard axis direction.

Therefore, demagnetization is unlikely to occur in the mother tape M, that is, the life of the mother tape M is extended, and the reproduction output of the information signal recorded on the blank tape B is high. Hereinafter, the present invention will be described with reference to specific examples.

[0016]

【Example】

Example 1 Using the oblique vapor deposition apparatus shown in FIG. 1, Co was deposited on one surface of a support (7 μm thick polyimide film).
A blank tape B was obtained by depositing —Ni (80-20) alloy particles to a thickness of 2000 Å (the supply amount of oxygen gas during film formation was 35 sccm).

The coercive force Hc ₂ of the blank tape B thus obtained as shown in FIG. ₂ is 1100 O.
e, saturation magnetic flux density Bs ₂ is 4000 G, residual magnetic flux density Br ₂
Was 3200G. In addition, a Cr undercoat film was deposited to a thickness of 500 Å by a sputtering means on one surface of a support (7 μm thick polyimide film, whose fiber direction is in the longitudinal direction) running on a heating roll heated to 200 ° C. And then Co / Cr / Pt (78: 1) on the Cr underlayer film on the support running on the heating roll heated to 250 ° C.
C: by sputtering means using a target of 0:12)
An o / Cr / Pt magnetic film was deposited to a thickness of 300Å to obtain a mother tape M having a horizontally magnetized film as shown in FIG.

The coercive force Hc ₁ of the mother tape M thus obtained is 3000 Oe, and the saturation magnetic flux density Bs ₁ is 7.
000 G and the residual magnetic flux density Br ₁ was 5900 G. Then, this mother tape M was set in a mirror mother making machine, and test signals of 1 MHz, 5 MHz and 10 MHz were written. Using the mother tape M and the blank tape B thus obtained, as shown in FIG. 5, the metal magnetic film of the mother tape M and the metal magnetic film of the blank tape B are superposed so as to be in contact with each other, and A mother tape M and a blank tape B are mounted on the magnetic transfer device shown in FIG. / S) mother tape M running at
Blank tape B running the recorded information signal of the same speed
Transferred to.

[Example 2] In Example 1, Co / C
A Co / Cr / Ta magnetic film was deposited to a thickness of 300Å on a Cr underlayer by a sputtering means using a target of r / Ta (85: 14: 1), and a mother having a horizontal magnetic film as shown in FIG. Tape M was obtained. The coercive force Hc ₁ of the mother tape M thus obtained is 2500 O
e, saturation magnetic flux density Bs ₁ is 7300G, residual magnetic flux density Br ₁
Was 5800G.

Using this mother tape M and the blank tape B of Example 1, the recording information signal of the mother tape M was transferred to the blank tape B in the same manner as in Example 1. [Comparative Example 1] In Example 1, the mother tape M is shown in FIG.
It was manufactured by using a 100% Co magnetic metal by an oblique vapor deposition apparatus as shown in FIG. The mother tape M has a coercive force Hc ₁ of 1800 Oe, a saturation magnetic flux density Bs ₁ of 5200 G,
The residual magnetic flux density Br ₁ was 4200G.

Then, this mother tape M is set in a mirror mother making machine, and 1 MHz, 5 MHz, 10 MHz
I wrote the test signal. Using the mother tape M thus obtained and the blank tape B of Example 1,
The recording information signal of the mother tape M was transferred to the blank tape B in the same manner as in Example 1.

[Characteristics] Blank tape B obtained in each of the above examples
The reproduction output was measured, and the results are shown in Table 1 below. Table-1 Reproduction output of blank tape B 1 MHz (dB) 5 MHz (dB) 10 MHz (dB) Example 1 0 1 2 Example 2 0 0.7 1.4 1.4 Comparative example 1 0 0 0 * The values of reproduction output are compared. Example 1 is displayed as 0 dB As can be seen from the above, the present invention enables copying on a blank tape having a high reproduction output and can copy at a high speed, so that mass production of software can be performed at a low cost. Like

Further, the recording information signal of the mother tape M is repeatedly transferred to the blank tape B, and the mother tape M is 3
When the number of times required until the dB is lowered is examined, there is no reduction of 3 dB even if it is repeated 12000 times in the case of Example 1, and 3d even if it is repeated 9000 times in the case of Example 2.
B did not decrease, but 6 in Comparative Example 1
It has already been reduced by 3 dB or more after repeating 000 times, which suggests that the present invention has high durability.

[0024]

According to the present invention, mass production of software with high reproduction output can be performed at low cost.

[Brief description of drawings]

FIG. 1 is a schematic view of an oblique deposition apparatus.

FIG. 2 is a schematic diagram of a blank tape.

FIG. 3 is a schematic diagram of a sputtering device.

FIG. 4 is a schematic diagram of a mother tape.

FIG. 5: Relationship diagram between mother tape and blank tape

FIG. 6 is a schematic view of a magnetic transfer device.

[Explanation of symbols]

 M mother tape (first magnetic recording medium) B blank tape (second magnetic recording medium)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Shigemi Wakabayashi Inventor Shigemi Wakabayashi 2606 Akabane, Kaiga-cho, Haga-gun, Tochigi Kao Co., Ltd.Institute of Information Science (72) Inventor Akira Shiga 2606 Akabane, Kaiga-cho, Haga-gun, Tochigi Kao Company Information Science Laboratory

Claims (4)

[Claims] 1. A second magnetic recording medium to which an information signal recorded on the first magnetic recording medium is transferred, wherein the first magnetic recording medium is a magnetic film having an easy axis of magnetization in an in-plane direction. The magnetic recording medium for transfer according to claim 2, wherein the second magnetic recording medium has a magnetic film in which a magnetic column grows obliquely with respect to a film surface. 2. A method for transferring an information signal recorded on a first magnetic recording medium to a second magnetic recording medium, wherein the first magnetic recording medium has a magnetic axis whose easy axis of magnetization is an in-plane direction. A second magnetic recording medium, wherein the second magnetic recording medium has a magnetic film in which a magnetic column grows obliquely with respect to the film surface, and the first magnetic recording medium and the second magnetic recording medium 2. The transfer method, wherein the magnetic films of the first magnetic recording medium and the first magnetic recording medium are made to run so that the magnetic films are positioned inside each other, and a bias magnetic field is applied from the side of the first magnetic recording medium. 3. The transfer method according to claim 2, wherein the bias magnetic field is applied in a direction perpendicular to the first magnetic recording medium. 4. The transfer method according to claim 2, wherein the bias magnetic field is applied by a ring head in a direction perpendicular to the surface of the first magnetic recording medium.