JPH0785472A - Magnetic recording medium manufacturing equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] Providing a technology that can quickly cool the magnetic metal inside the crucible, does not waste the magnetic metal, and has high production efficiency of the metal thin film magnetic recording medium. It is to be. [Structure] Evaporate the metal magnetic material contained in the container,
A magnetic recording medium manufacturing apparatus for forming a metal magnetic film by depositing on a support, the magnetic recording medium manufacturing apparatus comprising a mechanism for bringing a cooled metal magnetic material into contact with the metal magnetic material in the container. .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording medium manufacturing apparatus.

[0002]

BACKGROUND OF THE INVENTION In a magnetic recording medium such as a magnetic tape, due to a demand for high density recording, a binder resin is not used as a magnetic layer provided on a non-magnetic support, instead of a coating type using a binder resin. A metal thin film type that is not used has been proposed. That is, it is well known that a magnetic recording medium having a magnetic layer formed by a dry plating means such as vacuum deposition, sputtering or ion plating has been proposed. Since the magnetic recording medium of this type has a high packing density of magnetic material, it is suitable for high-density recording.

An apparatus for manufacturing a magnetic recording medium by such dry plating means is generally constructed as shown in FIG. In FIG. 2, reference numeral 21 denotes a cooling can, 22a
Is polyethylene terephthalate (PET) film 23
Of the PET film 23, a roll on the winding side of the PET film 23, a crucible 24, a magnetic metal 25, and a vacuum container 26. Then, after evacuating the inside of the vacuum chamber 26 to a predetermined vacuum degree, the electron gun is operated to evaporate the magnetic metal 25 in the crucible 24, and the evaporated particles of the magnetic metal 25 are deposited on the PET film 23 ( A magnetic recording medium is manufactured by vapor deposition.

However, there is a demand for further improvement in the industrial production efficiency of magnetic recording media using such a vapor deposition apparatus.

[0005]

DISCLOSURE OF THE INVENTION While the above-mentioned demands have been earnestly pursued, the production efficiency of a magnetic recording medium is low. Although it is designed to be cooled by a water cooling mechanism, it has been found that it takes more time to cool the magnetic metal inside than to cool the crucible 24, and therefore it takes longer than necessary to pause. .

If the degree of vacuum in the vacuum vessel 26 is lowered (opened to the atmosphere) without sufficiently cooling the magnetic metal in the crucible 24, the magnetic metal will be oxidized,
It becomes useless and wasteful. The present invention has been made from such a viewpoint, and an object of the present invention is to cool the magnetic metal inside the crucible quickly, without wasting the magnetic metal, and of the metal thin film type. It is an object of the present invention to provide a technique with high production efficiency of a magnetic recording medium.

An object of the present invention is a magnetic recording medium manufacturing apparatus for forming a metal magnetic film by evaporating a metal magnetic material contained in a container and depositing the metal magnetic material on a support. The present invention is achieved by an apparatus for manufacturing a magnetic recording medium, which comprises a mechanism for bringing a cooled metallic magnetic material into contact with the magnetic material. The cooled metallic magnetic material preferably has the same composition as the metallic magnetic material in the container.

[0008]

1 is a schematic view showing an embodiment of an apparatus for manufacturing a magnetic recording medium according to the present invention. In the figure, 1 is a cooling can, 2a is a supply-side roll, 2b is a winding-side roll, and polyester such as PET, polyamide, polyimide, polysulfone, polycarbonate, olefin resin such as polypropylene, cellulose resin A non-magnetic support 3 made of a polymer material such as vinyl chloride resin, an inorganic material such as glass or ceramics, or a metal material such as an aluminum alloy is fed from the supply side roll 2a and wound along the cooling can 1. It is adapted to be wound and then wound up on the winding side roll 2b.

An undercoat layer for improving the adhesion of the magnetic layer (magnetic thin film) is provided on the surface of the non-magnetic support 3. That is, by appropriately roughening the surface roughness, for example, the adhesion of the magnetic thin film formed by the oblique vapor deposition method is improved, and the surface roughness of the magnetic recording medium surface is moderated to improve the running property. Therefore, for example, the thickness containing particles such as SiO ₂ is 0.005 to 0.
The undercoat layer is formed by providing a coating film of 1 μm.

Reference numeral 4 denotes a crucible, and in this crucible 4,
For example, in addition to metals such as Fe, Co and Ni, Co-Ni alloys, Co-Pt alloys, Co-Ni-Pt alloys, Fe-C
o alloy, Fe-Ni alloy, Fe-Co-Ni alloy, Fe
-Co-B alloy, Co-Ni-Fe-B alloy, Co-C
r alloy, or these are filled with magnetic metal 5 such as Al or Ta.

As a constituent material of the crucible 4, for example,
MgO, ZrO, BeO, Al₂O ₃, Si₃N_Four, B
N, ThO₂, CaO, SiO₂, B_FourCeramic such as C
Weaving like a cous or plain weave or a weave
Examples include ceramics with intervening carbon fibers.
It Among them, the preferred one is B_FourC crucible
Is a crucible made of ceramics with a carbon fiber interposed.
It

Reference numeral 6 denotes a vacuum container, 7 denotes liquid nitrogen filled in a container provided outside the vacuum container 6, and 8 denotes a metal having a high heat conductivity, which is cooled by being immersed in the liquid nitrogen, for example, It is a copper ingot, and this copper ingot 8 is a part of the wall forming the vacuum container 6. That is, as shown in FIG. 1, the copper ingot 8 is disposed so as to be fitted to the bottom surface of the vacuum container 6, and the upper end portion 8a thereof is located below the crucible 4, which hinders the vapor deposition work. I'm made to not get up.
Further, the lower end portion 8b of the copper ingot 8 is cooled by the liquid nitrogen 7 so that the entire copper ingot 8 is cooled.
An O-ring 9 is provided between the copper ingot 8 and the vacuum container 6 in order to maintain the vacuum state of the vacuum container 6.

A cooling member 10 is made of a magnetic metal having the same composition as the magnetic metal 5 in the crucible 4. Cooling member 10
Is the crucible 4 by the linear motor 11 and the motor 12.
And the upper end portion 8a of the copper ingot 8 can be moved. The interior of the linear motor 11 is constructed as shown in the figure, and each coil enables smooth vertical movement. Then, during the vapor deposition work, the cooling member 10 is in contact with the upper end 8a and is cooled. When the vapor deposition work is stopped, the cooled cooling member 10 first rises vertically by the linear motor in FIG. Next, the cooling member is rotated together with the linear motor by the motor 12, stopped immediately above the crucible, and vertically lowered by the linear motor to contact the molten magnetic metal 5 and rapidly cool the molten magnetic metal 5. However, the surface is configured to be rapidly cooled and solidified.

In the apparatus constructed as described above, the inside of the vacuum container 6 is evacuated to a vacuum degree of about 10 ^-4 to 10 ^-6 Torr, and then the crucible 4 is heated by resistance heating, high frequency heating, electron beam heating or the like. The magnetic metal 5 in the inside is melted and evaporated to form 0.04 to 1 with respect to the support 3 such as a PET film.
A metal thin film type magnetic recording medium is manufactured by depositing the magnetic metal 5 having a thickness of μm. At the time of forming the magnetic thin film, it is preferable that oxygen is supplied to the vapor deposition portion and the surface layer portion of the magnetic thin film is oxidized by forced oxidation to form a protective layer of an oxide film. The thickness of the protective layer composed of this oxide film is about several tens of liters, and an oxide film of this thickness may be composed of natural oxidation. In some cases, no action is required.

In this way, the take-up roll 2b on which the support 3 having the magnetic thin film is wound is taken out, and is made of carbon black having an average particle diameter of 20 nm, vinyl chloride resin and urethane prepolymer. A coating material for a back coat in which the binder resin is dispersed is applied to the surface of the support 3 on the side opposite to the magnetic layer by a direct gravure method to provide a back coat layer having a dry thickness of 0.5 μm.

Fluorine perfluoropolyether (grade: FOMBLIN ZDIAC carboxyl group modified, manufactured by Nippon Montedison Co., Ltd.) was diluted to 0.1% in a fluorine inactive liquid (Fluorinert, FC-84, Sumitomo 3M).・ Apply the dispersed coating material on the magnetic surface side by a die coating method so that the thickness after drying is about 20Å, and dry at 70 ° C.

After that, a magnetic tape or the like is obtained by slitting to a predetermined width. By the way, when the above vapor deposition work is stopped for some reason, the crucible 4
In order to stop the melting and evaporation of the magnetic metal 5 inside,
At this time, if the cooled cooling member 10 is immediately brought into contact with the molten magnetic metal 5, the surface of the molten magnetic metal 5 is rapidly cooled and solidified.

In this way, even if the vacuum container 6 is opened to the atmosphere, the magnetic metal in the crucible 4 is unlikely to be oxidized,
In addition, the vacuum container 6 can be opened quickly. In other words, the magnetic metal inside the crucible is not wasted, and the production efficiency of the metal thin film type magnetic recording medium is high.

[0019]

According to the present invention, a metal thin film type magnetic recording medium can be efficiently produced without wasting magnetic metal.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of an embodiment of an apparatus for manufacturing a magnetic recording medium according to the present invention.

FIG. 2 is a schematic explanatory diagram of a conventional magnetic recording medium manufacturing apparatus.

[Explanation of symbols]

 1 Cooling Can 2a Supply Side Roll 2b Winding Side Roll 3 Support 4 Crucible 5 Magnetic Metal 6 Vacuum Container 7 Liquid Nitrogen 8 Copper Ingot 10 Cooling Member

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Shiga 2606 Akabane, Kai-cho, Haga-gun, Tochigi Prefecture Kao Co., Ltd.

Claims (2)

[Claims] 1. An apparatus for producing a magnetic recording medium, which comprises forming a metal magnetic film by evaporating a metal magnetic material placed in a container and depositing it on a support, wherein the metal magnetic material is cooled by the metal magnetic material in the container. An apparatus for manufacturing a magnetic recording medium, which is provided with a mechanism for contacting the metallic magnetic material. 2. The apparatus for manufacturing a magnetic recording medium according to claim 1, wherein the cooled metallic magnetic material has the same composition as the metallic magnetic material in the container.