JPH07296382A - Method and apparatus for transfer - Google Patents

Abstract

PURPOSE:To realize a low cost mass-production of software by disposing means for cooling a first magnetic recording medium closely to a transfer head dis posed oppositely to a guide means. CONSTITUTION:A mother tape 1 fed from a feed reel is made to touch arround a transfer drum 2 made of a high permeability material (permalloy) and rolled around a rewinding side reel (not shown). The motor tape 1 and a blank tape 3 are made to touch around the transfer drum 2 cooled down to 80 deg.K, as shown in the figure, thus performing the magnetic field transfer in a vacuum chamber of 10<-8>Torr. The transfer is effected by applying a bias field from a ring type magnetic head 4 disposed oppositely to the transfer drum 2. The transfer operation can be repeated 16000 times before the output of the mother tape 1 drops below 3dB.

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). Magnetic field transfer has been proposed as a means for achieving this. For example, JP-A-3-21442
In an apparatus configured to transfer by superposing a mother tape and a blank tape under pressure on a transfer drum as shown in Japanese Patent Laid-Open No. 7, run, and by applying a bias magnetic field to this. A technique has been proposed in which the transfer drum is made of a high magnetic permeability material.

It is said that this makes it possible to improve transfer characteristics even when a weak bias magnetic field is used.
In other words, it is considered that the mother tape does not easily demagnetize because the bias magnetic field is small, and the mother tape has high durability. However, this is not enough and further technology is required.

[0004]

DISCLOSURE OF THE INVENTION It is an object of the present invention to provide a copying technique in which a mother tape has excellent durability and excellent transfer characteristics. An object of the present invention is a method for transferring an information signal recorded on a first magnetic recording medium to a second magnetic recording medium, the method comprising the steps of forming a first magnetic recording medium and a second magnetic recording medium. Steps of superposing, applying a bias magnetic field to the superposed first magnetic recording medium and second magnetic recording medium, and cooling the first magnetic recording medium in the vicinity where the bias magnetic field is applied. And a transfer method comprising:

In particular, a method of transferring an information signal recorded on a first magnetic recording medium to a second magnetic recording medium, the method comprising the step of running the first magnetic recording medium along a transfer drum, A step of causing a second magnetic recording medium to run over the first magnetic recording medium running along the transfer drum, a step of cooling the transfer drum, and a first step of running along the transfer drum in an overlapping manner. And applying a bias magnetic field to the second magnetic recording medium from the side of the second magnetic recording medium.

In the present invention, the first magnetic recording medium on which the information signal is already recorded is subjected to the positive cooling action, but the second magnetic recording medium is the first magnetic recording medium. It does not receive a positive cooling action other than the cooling action from the side of the magnetic recording medium. Then, when cooling is performed, a dew condensation phenomenon usually occurs, which adversely affects the magnetic recording medium. Therefore, it is preferable that the dew condensation is substantially prevented.
For example, in a vacuum atmosphere (for example, an atmosphere having a vacuum higher than 10 ⁻⁸ Torr), or in a dry H ₂ atmosphere, dry A
It is preferable to say that the transfer operation is performed in an r atmosphere or a dry He atmosphere.

Another object of the present invention is an apparatus for transferring an information signal recorded on a first magnetic recording medium to a second magnetic recording medium, wherein the first magnetic recording medium is Guide means arranged on the near side and guiding the polymer of the first magnetic recording medium and the second magnetic recording medium, a transfer head arranged opposite to the guide means, and the vicinity of the transfer head. And a cooling means for cooling the first magnetic recording medium at the position (1).

The cooling means in the present invention is the first
If the guide means (particularly the transfer drum) with which the magnetic recording medium is in contact is cooled, the overall structure can be simplified. Further, it is preferable that the guide means (particularly, the transfer drum) is made of a material having high magnetic permeability.

The basic principle of the present invention is based on the following facts. That is, it is based on the fact that the thermal fluctuation is small and the coercive force and the saturation magnetization are high when the ferromagnetic material is at a low temperature. By the way, even if a bias magnetic field is applied during transfer, if the demagnetization due to this is unlikely to occur, the applied bias magnetic field does not necessarily need to be made small, and transfer efficiency is improved. When the temperature is kept low, the thermal fluctuation is small, and the coercive force and the saturation magnetization are high. Therefore, by lowering the temperature of the mother tape on which the information signal is recorded, the problem of demagnetization of the mother tape is improved. Like If the idea is reversed, it is easier to record on the blank tape if the temperature of the blank tape is raised, and therefore the bias magnetic field applied can be reduced. It is hard to be demagnetized.

It has been already known that when the ferromagnetic material is at a low temperature, the thermal fluctuation becomes small, and the coercive force and the saturation magnetization become high. However, it was not considered by anyone to try to apply this phenomenon when transferring the information signal recorded on the mother tape to the blank tape. That is, there was no idea to apply the above phenomenon to the magnetic field transfer technique.

In the present invention, the mother tape is cooled in order to prevent demagnetization of the mother tape. Various methods are conceivable as this cooling method. By the way, in magnetic field transfer, a transfer drum that guides the running of a mother tape or a blank tape is usually used. Therefore,
If the transfer drum is cooled to, for example, 25 to 100 ° K and the mother tape is attached to the transfer drum, the mother tape is cooled efficiently. The idea of attaching this mother tape to the transfer drum also played a major role in achieving the present invention. This is because in the past, a blank tape was attached to the transfer drum, so even if the mother tape is cooled, the idea of cooling the mother tape is also changed unless the idea of tape attachment to the transfer drum is changed. It seems that it would not have happened.

The transfer drum can be easily cooled by using liquid nitrogen or the like. At this time, if the amount of water in the atmosphere is large, this causes dew condensation and has an adverse effect. Therefore, the amount of water is preferably small. For this reason, it is preferable that the portion where the polymer of the mother tape and the blank tape is guided by the guide means is at least located in the vacuum chamber or the drying chamber. For example, it is preferable that the main part or the entire part where the transfer is performed is installed in a vacuum chamber or a drying chamber.

The mother tape used in the present invention is a metal thin film type in which the columns of the magnetic film are grown obliquely, and the blank tape used in the present invention is
It is preferable that the column of the magnetic film is of a thin metal film type grown obliquely. In particular, it is preferable that the column inclination θ ₂ of the magnetic film of the blank tape is smaller than the column inclination θ ₁ of the magnetic film of the mother tape.

Note that θ ₁ is 20 to 80 ° and θ ₂ is 5
It is preferably -60 °. That is, θ ₁ > θ ₂
By satisfying the conditions that θ ₁ is 20 to 80 ° and θ ₂ is 5 to 60 °, demagnetization can be further reduced and good output can be obtained. Also, θ
By satisfying the condition of _1- θ ₂ of 15 to 75 °, demagnetization was further reduced and good output was obtained.

Then, the magnetic tapes of the mother tape are superposed so that the column growth direction of the magnetic film intersects with the column growth direction of the blank tape magnetic film, and the magnetic films are positioned inside. The tapes are superposed so as to be positioned on the side of the cooled transfer drum, and the bias magnetic field is applied from the side of the blank tape, whereby the transfer is efficiently performed.

The support used in the magnetic recording medium of the present invention is a non-magnetic support, and such a support includes polyester such as PET, polyamide, polyimide, polysulfone, polycarbonate, olefin resin such as polypropylene, Organic materials such as cellulosic resins and vinyl chloride resins, ceramics such as glass, and other metallic 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, the undercoat layer is formed by providing a coating film containing particles such as SiO ₂ and having a thickness of 0.05 to 0.5 μm.

A magnetic thin film is provided on one surface of such a support by, for example, oblique vapor deposition means. Examples of the material of the magnetic particles forming the metal magnetic thin film include Fe and C
In addition to metals such as o and Ni, Co-Ni alloys, Co-Pt
Alloy, Co-Ni-Pt alloy, Fe-Co alloy, Fe-
A Ni alloy, an Fe-Co-Ni alloy, an Fe-Co-B alloy, a Co-Ni-Fe-B alloy, a Co-Cr alloy, or those containing a metal such as Al is used. Also, Fe-N alloy, Fe-N-O alloy, Fe-C
Alloys, Fe-C-O alloys, etc. are also 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. Further, it is more preferable that diamond-like carbon, boron carbide, silicon nitride, or the like is further provided as the protective layer. Further, it is preferable to provide a fluorine-based or carbon-based lubricant on the upper layer of the protective layer.

When the information signal is copied as described above, demagnetization is unlikely to occur in the mother tape, and the information signal can be copied repeatedly and accurately. Hereinafter, the present invention will be described with reference to specific examples.

[0019]

【Example】

[Embodiment 1] FIG. 1 is a schematic view showing a first embodiment of a transfer device according to the present invention. In the figure, 1 is a mother tape for 8 mm VTR in which a predetermined information signal is recorded,
The mother tape 1 is attached to a transfer drum 2 made of a high-permeability material (permalloy) from a supply-side reel (not shown), and wound on a winding-side reel (not shown).

The mother tape 1 is made of PET having a thickness of 15 μm.
The magnetic metal Co is deposited on the film 240 by the oblique deposition means.
It has a thickness of 0Å and has a magnetic property of Hc of 16
80 Oe, Bs is 6700 G, Br / Bs is 0.84,
θ ₁ is 60 °. An oxidizing gas was supplied when the Co vapor deposition film was formed, and the Co vapor deposition film surface layer was oxidized. Further, a fluorine-based lubricant is applied to the surface, and a back coat layer containing carbon black is provided on the surface opposite to the Co vapor deposition film.

The information signal is recorded in a pattern opposite to the normal track pattern. 3 is a blank tape, which is attached to the transfer drum 2 from a supply-side reel (not shown) and then wound onto a winding-side reel (not shown). That is, the mother tape 1 and the blank tape 3 are attached to the transfer drum 2 in an overlapped state, and this relationship is maintained and they travel as shown by the arrow. In addition, the form of superposition of the mother tape 1 and the blank tape 3 is as follows:
Growth direction of column and blank tape 3 in magnetic film
So that the column growth direction in the magnetic film of
In addition, the magnetic films are superposed so that the magnetic films are located inside.

The blank tape 3 is made of PE having a thickness of 10 μm.
The magnetic metal Co-Ni (80:20) was provided on the T film by an oblique vapor deposition means to a thickness of 1800Å, and the magnetic characteristics were Hc of 1080 Oe and Bs of 5200.
G and Br / Bs are 0.77 and θ ₂ is 25 °. still,
Oxidizing gas is being supplied when the Co vapor deposition film is formed,
The surface layer of the Co-Ni deposited film is oxidized. Further, a fluorine-based lubricant is applied to the surface, and a back coat layer containing carbon black is provided on the surface opposite to the Co—Ni vapor deposition film.

Then, the mother tape 1 and the blank tape 3 were attached to the transfer drum 2 cooled to 80 ° K as shown in FIG. 1, and magnetic field transfer was performed in a vacuum chamber of 10 ^-8 Torr. The transfer is performed by applying a bias magnetic field from a ring-type magnetic head 4 provided opposite to the transfer drum 2. When the transfer was repeated in this way and the number of times until the output of the mother tape 1 was reduced by 3 dB was examined, it was found that the number was 16,000 times.

[Example 2] The same procedure as in Example 1 was carried out except that the transfer drum 2 was cooled to 100 ° K. When the transfer was repeated in this manner and the number of times until the output of the mother tape 1 was reduced by 3 dB was examined, it was found that the number was 15,000 times. [Third Embodiment] In the first embodiment, the transfer drum 2 is set to 50 °.
The same procedure was performed except that the temperature was cooled to K.

When the transfer was repeated in this way and the number of times until the output of the mother tape 1 was reduced by 3 dB was examined, it was found that the number was 18,000 times. Example 4 The transfer device shown in FIG. 2 was used instead of the transfer device shown in FIG. That is, in order to make it difficult for the blank tape 3 to be cooled, the guide roller 5 is provided in the running path of the blank tape 3, and the blank tape 3 is attached to the transfer drum 2 with the mother tape 1 sandwiched therebetween. The splicing length is shortened.

Others were the same as in Example 1. still,
The bias magnetic field was weakened by about 20%. When the transfer was repeated in this manner and the number of times until the output of the mother tape 1 was decreased by 3 dB was examined, it was found that the number was 18,000 times. [Comparative Example 1] In Example 1, the transfer drum 2 was replaced with 298.
The same procedure was performed except that the temperature was kept at ° K.

When the transfer was repeated in this way and the number of times until the output of the mother tape 1 was reduced by 3 dB was examined, it was only 12000. As can be seen, according to the present invention, copying onto a blank tape can be performed efficiently and at high speed, demagnetization of the mother tape is unlikely to occur, and mass production of software can be performed at low cost.

[0028]

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

[Brief description of drawings]

FIG. 1 is a schematic view of a transfer device according to a first embodiment of the present invention.

FIG. 2 is a schematic view of a transfer device according to a second embodiment of the present invention.

[Explanation of symbols]

 1 mother tape 2 transfer drum 3 blank tape 4 ring type magnetic head 5 guide roller

 ─────────────────────────────────────────────────── ─── 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 (6)

[Claims] 1. A method for transferring an information signal recorded on a first magnetic recording medium to a second magnetic recording medium, the method comprising: stacking the first magnetic recording medium and the second magnetic recording medium. And a step of applying a bias magnetic field to the first magnetic recording medium and the second magnetic recording medium which are stacked, and a step of cooling the first magnetic recording medium in the vicinity where the bias magnetic field is applied. A transfer method comprising: 2. A method for transferring an information signal recorded on a first magnetic recording medium to a second magnetic recording medium, the method comprising: running the first magnetic recording medium along a transfer drum. Running a second magnetic recording medium over the first magnetic recording medium running along the transfer drum;
Cooling the transfer drum, and applying a bias magnetic field from the side of the second magnetic recording medium to the first magnetic recording medium and the second magnetic recording medium that run along the transfer drum in an overlapping manner. A transfer method comprising the steps of: 3. The first magnetic recording medium according to claim 1, wherein the second magnetic recording medium is prevented from being actively cooled except for being cooled by the first magnetic recording medium. Item 2. The transfer method according to item 2. 4. The transfer method according to claim 1, wherein the cooling is performed so that dew condensation does not substantially occur on the magnetic recording medium. 5. An apparatus for transferring an information signal recorded on a first magnetic recording medium to a second magnetic recording medium, wherein the first magnetic recording medium is arranged on the near side, and Guide means for guiding the polymer of the first magnetic recording medium and the second magnetic recording medium, a transfer head arranged opposite to the guide means, and a first magnetic member at a position near the transfer head. A transfer device comprising: a cooling unit that cools a recording medium. 6. The transfer device according to claim 5, wherein the cooling means is configured to cool the guide means with which the first magnetic recording medium is in contact.