JPH11353650A - Apparatus for producing magnetic recording medium and production of magnetic recording medium using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the generation of splashes and to improve a working rate and productivity by constituting the contamination member existing in an upper part of contamination members of a travelable belt-like contamination member and parting the end of the contamination member existing in the lower part in a central direction of a cooling can roll from right above the melting part of a crucible. SOLUTION: Deposits are respectively deposited by ineffective vapor on the belt-like contamination member 24 and the contamination plate 13 simultaneously as vapor deposition starts. Since the belt-like contamination member 24 travels at a prescribed speed at all times, the deposits are melted and are transported in a direction parting from right above a magnetic material 8 and the stagnation of the deposits at one point and the growth thereof are prevented. The deposits grow even at the end 13a of the contamination plate 13 but even if these deposits fall, the end 13a exists in the position parting from right above the molten magnetic material 8 and, therefore, the deposits fall to the outside of the crucible 9 and the generation of the splashes of the melt is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for manufacturing a magnetic recording medium by oblique vapor deposition and a method for manufacturing a magnetic recording medium using the apparatus.

[0002]

2. Description of the Related Art In recent years, thin-film magnetic tapes manufactured by using an oblique deposition method have been widely used mainly for audio devices and video camera devices. Conventionally, as shown in FIG. 2, an apparatus for manufacturing a magnetic tape by the oblique deposition method has been generally used. That is, in FIG. 2, a cooling can roll 2, an unwind roll 3, a take-up roll 4, and guide rolls 5 and 6 are arranged in a vacuum chamber 1, and a base film 7 is wound between these rolls. The base film 7 travels in the direction of the arrow in the figure as the cooling can roll 2 rotates. On the other hand, a crucible 9 containing an evaporating material, that is, a magnetic material 8, is provided below the cooling can roll 2, and an electron gun, for example, a pierce-type electron gun 10 installed on the wall of the vacuum chamber 1 emits an electron beam. By irradiating the magnetic material 8 with 11, the magnetic material 8 is melted and evaporated, and the vapor flow is adhered to and deposited on the surface of the base film 7 to form a magnetic layer.

In order to form an opening for controlling the angle of incidence of the vapor flow of the magnetic material 8 with respect to the base film 7,
Deposition members Here, deposition plates 12 and 13 are provided.
Specifically, the maximum incident angle θmax is determined by the lower end 12a of the deposition-preventing plate 12 located at a position farther from the upper part, that is, the crucible 9.
However, when viewed from the lower part, that is, from the crucible 9, the minimum incident angle θmi
n is regulated respectively. Generally, θmax = 90
It is known that magnetic characteristics and productivity are improved when ° and θmin = 40 ° to 50 °.

[0004]

However, the conventional magnetic recording medium manufacturing apparatus as described above has the following problems. That is, in the course of the evaporation, the deposits 14 due to the invalid vapor are deposited on the ends 12a and 13a of the deposition-preventing plates 12 and 13, and when the amount of the deposits 14 increases, the deposits 14 fall in an extreme case. Would. Deposition plate 1
Since both ends 12a and 13a of 2 and 13 are located immediately above the magnetic material 8 melted in the crucible 9, when the attached matter 14 falls, a splash occurs and the base film 7
There is a possibility that a defect may occur on the deposition surface of.

For this reason, measures have been taken to improve the adhesion by roughening the surfaces of the deposition-preventing plates 12 and 13, but when the weight of the deposit exceeds the adhesion of the deposition-preventing plates. Is difficult to prevent falling. Therefore, during the deposition process,
It is necessary to perform the operation of removing the deposit every predetermined period. For this operation, the vacuum in the vacuum chamber must be broken, and the heating of the crucible must be interrupted.
This resulted in a significant decrease in production efficiency.

[0006]

In order to solve the above-mentioned problems, the present inventor has conducted various studies. First, the present inventors have found that by preventing growth of a deposit at one location, the fall of the deposit is prevented. Secondly, instead of preventing the attachment itself from dropping on the deposition-preventing plate itself, if the attachment falls, it is allowed to fall out of the molten evaporative material, thereby preventing splash. The present invention has been completed from a viewpoint.

That is, according to the present invention, a magnetic material is evaporated from a crucible in a vacuum chamber, and the vapor flow is adhered and deposited on a substrate running on the outer peripheral surface of a cooling can roll by oblique evaporation. At a position close to the cooling can roll at the top of the crucible, a magnetic recording medium manufacturing apparatus having a deposition-preventing member that regulates an opening for controlling the incident angle of the vapor flow, The upper deposition-preventing member is constituted by a movable strip-shaped deposition-preventing member, and the end of the lower deposition-preventing member is separated from the melting portion of the crucible toward the center of the cooling can roll. Is provided. In the above configuration, it is preferable that the belt-shaped deposition-preventing member is formed of a metal ribbon. Further, according to the present invention, there is provided a method for manufacturing a magnetic recording medium using the above-described manufacturing apparatus.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an apparatus for manufacturing a magnetic recording medium according to the present invention will be described with reference to FIG. In the drawing, the same components as those in FIG. 2 are denoted by the same reference numerals. In the manufacturing apparatus of the present invention,
Instead of the upper deposition-inhibiting member, that is, the conventional deposition-preventing plate 12,
A runnable belt-shaped deposition-inhibiting member 24 is provided. In particular,
Unwind roll 21, take-up roll 22, guide roll 2
3, a belt-shaped deposition-inhibiting member 24 is wound and is run in the direction of the arrow in the figure. The constituent material of the belt-shaped deposition-inhibiting member 24 is not particularly limited. However, in consideration of being exposed to a high-temperature vapor flow, for example, a thin strip formed of a metal material such as SUS or W (tungsten) is used. It is preferred to use The thickness of this metal strip is
It is desirable to appropriately determine the magnitude of the heat applied to the ribbon. Further, the ribbon may be cooled if necessary.

On the other hand, a protection plate 13 close to the crucible 9 has the same construction as the conventional protection plate 13 shown in FIG. 2, but the left end 13a is located at the position of the molten magnetic material in the crucible 9. It is necessary to install the cooling can roll 2 at a position more distant from the center side of the cooling can roll 2 than immediately above. In the above configuration, the guide roll 23 that guides the belt-shaped deposition-preventing member 24 is used.
, The maximum incident angle θmax of the vapor flow,
3, the minimum incident angle θmin is regulated by the left end 13a.

In such a manufacturing apparatus, deposits are deposited on the belt-shaped deposition-preventing member 24 and the deposition-preventing plate 13 by means of invalid steam at the start of vapor deposition. However, since the belt-shaped attachment member 24 is always running at a predetermined speed, the attached matter is melted and transported in a direction away from immediately above the magnetic material 8, and the attached matter stays at one place and grows. To prevent At the end 13a of the attachment-preventing plate 13, the attached matter also grows.
Since “a” is located at a position separated from immediately above the molten magnetic material 8, the attached matter falls to the outside of the crucible 9, and splash of the molten material is prevented. Therefore, continuous vapor deposition on the base film 7 can be performed for a long time, and the operation rate and production efficiency of the apparatus are greatly improved.

<Example> A magnetic tape was manufactured using the apparatus shown in FIG. That is, a PET (polyethylene terephthalate) film having a thickness of 6 μm and a total length of 10,000 m was used as the base film 7, and Co was used as the magnetic material. The diameter of the cooling can roll is 1000m
m and the traveling speed of the base film 7 is 50 m / min.
And On the other hand, the thickness of the belt-shaped deposition-inhibiting member 24 is 100 μm.
The SUS was used to run at a speed of 0.5 m / min to perform vapor deposition. In the vapor deposition step, the magnetic material made of CoO was melted and evaporated by an electron beam while the oxygen of the pierce-type electron gun was set to 100 kW and oxygen was introduced into the vacuum chamber.
Was formed to a thickness of In this step, the maximum incident angle θmax = 90 ° of the steam flow and the minimum incident angle θmin = 40 in this step.
°.

In the above-described process, there is no drop of the deposit from the band-shaped deposition preventing member 24 over the entire length of the base film 7, and the deposition of the deposit from the deposition prevention plate 13 occurs several times. In each case, no splash was generated due to dropping to the outside of the crucible 9, and a magnetic tape having no defect could be manufactured.

For comparison, vapor deposition was performed using the conventional apparatus shown in FIG. 2 under the same conditions as in the above embodiment. The attachments fall from the crucible 9, and the attachments fall from the deposition-preventing plate 13, starting from the 800 m film length.
Of the magnetic tape 8, a splash occurred, and a defect occurred on the surface of the magnetic tape. As is clear from the above results, if a magnetic tape is manufactured using the manufacturing apparatus of the present invention, continuous vapor deposition can be performed for a much longer time than in the case where a conventional apparatus is used. It was confirmed that the operation rate and production efficiency were significantly improved.

[0014]

As described in detail above, according to the present invention,
In the vapor deposition process, the occurrence of splash due to the deposits due to the ineffective vapor falling into the molten magnetic material is prevented, enabling continuous vapor deposition for a long time, greatly improving the operation rate and production efficiency of the equipment. Can be improved.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an example of a configuration of a main part of a manufacturing apparatus of the present invention.

FIG. 2 is a conceptual diagram showing an example of a configuration of a main part of a conventional manufacturing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vacuum tank 2 Cooling can roll 3, 21 Unwind roll 4, 22 Take-up roll 5, 6, 23 Guide roll 7 Base film 8 Magnetic material 9 Crucible 10 Pierce type electron gun 11 Electron beam 12, 13 Deposition plate 24 Strip shape Deposition material

Claims (3)

[Claims] 1. A magnetic material is evaporated from a crucible in a vacuum chamber, and the vapor flow is adhered and deposited on a base material running on the outer peripheral surface of a cooling can roll by an oblique evaporation method. An apparatus for manufacturing a magnetic recording medium, comprising: a deposition prevention member that regulates an opening for controlling an incident angle of the vapor flow at a position close to a roll; Magnetic recording wherein the member is constituted by a strip-shaped arresting member capable of traveling, and an end of the arresting member located at a lower portion is separated from a position directly above a melting portion of the crucible toward a center of a cooling can roll. Media manufacturing equipment. 2. The apparatus for manufacturing a magnetic recording medium according to claim 1, wherein the belt-shaped deposition-preventing member is formed of a metal ribbon. 3. A method for manufacturing a magnetic recording medium using the manufacturing apparatus according to claim 1.