JPH06111312A - Magnetic recording medium producing device - Google Patents

Abstract

PURPOSE:To produce a magnetic recording medium producing device capable of surely collecting liq. droplets. CONSTITUTION:This magnetic recording medium producing device consists of a vacuum vessel 1, a device 2, arranged in the vessel 1 and used to travel a series of materials to be vapor-deposited, a crucible 3 furnished below the material and an electron beam generator to irradiate a magnetic material in the crucible 3 with an electron beam. The crucible 3 is produced with a net means 13 arranged above a melting tank 9 and an exciting means 19 for vibrating the net means 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for producing a vapor deposition type magnetic recording medium in which vapor of a magnetic material is vapor deposited to form a magnetic layer, and more particularly to a crucible constituting an evaporation source thereof.

[0002]

2. Description of the Related Art As a conventional vapor deposition type magnetic recording medium manufacturing apparatus, a vacuum container, a traveling device for traveling a series of materials to be vapor-deposited in the vacuum container, and a device disposed below the material to be vapor deposited. Some include a crucible having a melting tank for magnetic material, and an electron beam generator for irradiating the magnetic material of the crucible with an electron beam. Then, the magnetic material in the melting tank of the crucible was irradiated with an electron beam, whereby the magnetic material was irradiated with the electron beam to be melted and continued to evaporate, and the vapor was deposited on the deposition target material.

[0003]

Impurities and oxides from magnetic materials float on the liquid surface of the melting tank of the crucible. When this is irradiated with an electron beam, these impurities and oxides do not melt easily because they have a high melting point, and they are heated to a very high temperature. When the liquid surface comes into contact therewith, evaporation rapidly occurs at the contacted portion, which induces scattering of droplets. This droplet is called a splash and adheres to the material to be vapor-deposited to become a projection foreign matter. If there is such a protruding foreign substance, the magnetic head rides on this during recording / reproduction, and the distance between the magnetic head and the material to be vapor-deposited becomes too wide, and normal recording / reproduction cannot be performed.

The present invention has been made in view of the above problems, and an object thereof is to form a proper vapor deposition film on a material to be vapor-deposited so that the splash does not adhere to the material to be vapor-deposited. The present invention intends to provide a novel magnetic recording medium manufacturing apparatus configured as described above.

[0005]

A magnetic recording medium manufacturing apparatus according to the present invention comprises a vacuum container, a traveling device for traveling a series of materials to be vapor-deposited disposed in the vacuum container, and a device below the material to be vapor-deposited. In a manufacturing apparatus for a magnetic recording medium, which comprises a crucible having a melting tank for magnetic material and an electron beam generator for irradiating the magnetic material of the crucible with an electron beam, the crucible is located above the melting tank. It is characterized in that it is provided with a net means provided and an exciting means for vibrating the net means.

In the present invention, the crucible is provided with a net means and an exciting means. The mesh means is arranged above the melting tank of the crucible and catches droplets (splash) scattered from the liquid surface of the melting tank by the mesh, thereby preventing the droplets from reaching the material to be vapor-deposited. It is intended to prevent adhesion. The mesh size may be, for example, 100 to 500 mesh. Further, as the material of the mesh means, a metal material having a high melting point, for example, tungsten, heat resistant alloy, heat resistant steel or the like can be used. The mesh means is at least large enough to cover the liquid level of the melting tank.

The vibrating means vibrates the mesh means to prevent the droplets from passing through the mesh, and also to shake off the droplets clogging the mesh.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an apparatus for manufacturing a magnetic recording medium according to the present invention. The present apparatus includes a vacuum container 1, a traveling device 2, a crucible 3, and an electron beam generator 4. A discharge port 9 of the vacuum container 1 is connected to a vacuum pump (not shown), and a traveling device 2 for running a series of materials to be vapor-deposited, that is, a synthetic resin tape 5, is arranged in the vacuum container. The traveling device 2 includes a feed roll 6 and
It comprises a winding roll 7 and a cooling can 8. The crucible 3 is arranged at a position closer to the right side of the drawing than directly below the cooling can 8. The crucible 3 is made of MgO and can withstand a high temperature of 1400 ° C to 1500 ° C. Further, the crucible 3 includes a melting tank 9, and the magnetic metal 10 is housed in the melting tank 9. The electron beam generator 4 includes an electron gun 11, and the electron gun 1
1 emits an electron beam, and the electron beam is emitted from the melting tank 9
The magnetic metal 10 inside is irradiated.

A shielding plate 12 is arranged below the cooling can 8 and close to the cooling can, and its tip is located slightly above the lowermost end of the cooling can.

The crucible 3 includes a mesh means 13 and an exciting means 14.
It has and. The mesh means 13 has a dome shape,
It is provided above the melting tank 9 so as to cover the entire crucible 3. The mesh means 13 is made of tungsten,
It has a mesh that is large enough to catch droplets scattered from the liquid surface of the melting tank 9. The excitation means 14 is mainly composed of an ultrasonic wave generator and a vibrator. Then, the electric vibration (for example, the frequency of 50 to 10) generated by this ultrasonic generator is generated.
0 KHz) is converted into mechanical vibration of the vibrator, and ultrasonic vibration of this vibrator is applied to the net means 13.

In the apparatus of the present invention thus constructed, when the electron beam is directed toward the magnetic metal 10 by the electron gun 11, the magnetic metal 10 is irradiated with the electron beam to melt and continue to evaporate. The tape 5 fed out from the feed roll 6 and entering the evaporation region rotates in the circumferential direction on the cooling can while receiving the oblique deposition of the magnetic metal vapor, and the oblique magnetic film is formed on the tape in the meantime. And is wound by the winding roll 7.

The mesh means 13 reliably catches the droplets scattered from the liquid surface of the melting tank 9 by the mesh, and prevents the droplets from reaching the tape 5. The excitation means 14 is the net means 1
Ultrasonic vibration is applied to 3 so that small droplets that try to pass through the mesh are reliably captured, and droplets clogging the mesh are shaken off. This ensures that the droplets are captured, thus preventing them from reaching the tape 5,
As a result, a proper vapor deposition film is formed on the tape 5.

(Experimental Example) Using the apparatus of the present invention having the above-described structure, a polyethylene terephthalate tape having a thickness of 9.5 μm and a vapor deposited film of a magnetic material of Co—Ni (80-20%) of 1500 angstroms was formed. Formed to a thickness of.

On the other hand, as a comparative example, a vapor-deposited tape was prepared under the same conditions as in the experimental example, with the mesh means and the exciting means removed.

Both of them were mounted on an 8-mm reproducing apparatus and their dropouts were compared, and the following results were obtained.

[0017]

[Table 1]

(Note) For the measurement of dropout, a dropout counter is used, and one drop in -16 dB output within 10 μs is counted, and the number of drops per minute is counted.

According to the device of the present invention equipped with the net means and the excitation means, the defects (the number of dropouts) were reduced by about 60% as compared with the case where the net means and the excitation means were not provided.

[0020]

Since the apparatus of the present invention is provided with the mesh means arranged above the melting tank and the exciting means for vibrating the mesh means, the liquid droplet (splash on the liquid surface of the melting tank is splashed. ) Can be reliably captured, so that the droplets are prevented from reaching the material to be vapor-deposited, and as a result, a high-quality magnetic recording medium can be obtained.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an apparatus for manufacturing a magnetic recording medium according to the present invention.

[Explanation of symbols]

 1 Vacuum Container 2 Traveling Device 3 Crucible 4 Electron Beam Generator 5 Tape (Material to be Evaporated) 8 Cooling Can 9 Melting Tank 10 Magnetic Metal 13 Net Means 14 Excitation Means

Claims (1)

[Claims] 1. A vacuum container, a traveling device for traveling a series of materials to be vapor-deposited arranged in the vacuum container, a crucible having a melting tank of a magnetic material arranged below the material to be vapor-deposited, and the crucible. An apparatus for producing a magnetic recording medium including an electron beam generator for irradiating the magnetic material with an electron beam, wherein the crucible is for vibrating the mesh means disposed above the melting tank. A magnetic recording medium manufacturing apparatus.