JPS63209028A - Apparatus for producing magnetic recording medium - Google Patents

Abstract

PURPOSE:To obtain a magnetic recording medium which has less ruggedness on a surface and has excellent magnetic characteristics and film strength by forming a roll surface to the smoothness lower than the smoothness of a specular surface to create a space between a tape and the roll surface. CONSTITUTION:The space is partially provided between the film and the roll. While the long-sized base film 3 is continuously taken up, a magnetic metallic film is deposited on the surface thereof. Heating and vapor deposition of the base film 3 are executed on a main roll 4. The roller 4 surface of a vacuum deposition device is worked to the accuracy of some 'rough state' or a method of covering the roll surface with a net consisting of material such as metal or glass wool is adopted. The adequate degree of the adhesion between the film and the roll is thereby obtd. and the gas generated from the film at the time of degassing and vapor deposition is smoothly diffused. The film having no ruggedness is prepd. and the heat conductivity between the base film and the roll decreases; therefore, the diffusion rate of the heat which the film receives at the time of vapor deposition is lowered and the attainment of a quickly cooled state is prevented. The formation of the magnetic recording medium having the excellent magnetic characteristics and film strength at the low substrate temp. is thereby permitted.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for manufacturing a magnetic recording medium in which a magnetic material such as a magnetic metal thin film or a metal oxide thin film is deposited on the surface of a long film.

[Conventional technology]

As a conventional magnetic recording medium manufacturing apparatus, an apparatus as described in "Vacuum Deposition" published by Nikkan Kogyo Shimbun, pages 310 to 311 is known. This device is equipped with a means in a vacuum device to run a plastic film wound on a roll over an evaporation source while unwinding it from the roll, and can continuously vapor deposit a metal film.

[Problem that the invention seeks to solve]

In the above-mentioned conventional technology, it is common to improve the processing accuracy of the surface of the main roll that feeds the film at the film deposition position as much as possible to give it a clean surface finish. The purpose of this is to prevent the film from being damaged and to improve the adhesion between the base film and the main roll to improve heat conduction. polyester terephthalate) (PET
) When a base film with poor heat resistance is used, the latent heat of the metal particles is quickly absorbed by the roll during sputtering and vapor deposition, which has a great effect in reducing the heat load applied to the base film.

However, on the other hand, when the main roll is heated and a base film having heat resistance such as polyimide is used, there are problems described below. One is that the surface finish of the roll is poor, which makes it difficult for gas generated between the base film and the roll to escape during vapor deposition, resulting in unevenness on the base film. Because of the cooling, the effective substrate temperature drops, making it impossible to obtain desired physical properties such as magnetic properties and film strength.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to provide an apparatus for manufacturing a magnetic recording medium with less surface irregularities and excellent magnetic properties and film strength.

[Means for solving problems]

The above purpose is to make the roll surface lower than a mirror surface, and
The solution is to create a space between the tape and the roll surface.

For example, in the present invention, the processing accuracy of the roller surface is set in the range of JISBO 6-9 12-8 to 50O8, contrary to the conventional method.
More preferably, the roll is processed into a "rough state" having a particle size in the range of 50-8 to 100S, or the surface of the roll is covered with a mesh made of metal, glass wool, or the like. As a result, the degree of adhesion between the film and the roll is appropriate, the gas generated from the film during degassing and vapor deposition can be smoothly diffused, a film with no unevenness can be produced, and the thermal conductivity between the base film and the roll can be improved. This reduces the rate of diffusion of heat received by the base film during vapor deposition, preventing rapid cooling, making it possible to form magnetic recording media with excellent magnetic properties and film strength at low substrate temperatures. Stainless steel, phosphor bronze, glass wool, etc. are used as the material for the MEC&.

〔Example〕

Hereinafter, the details of the present invention will be explained with reference to examples.

Example 1 FIG. 1 is a conceptual diagram of a vacuum evaporation apparatus that coats a metal magnetic film on the surface of a long base film 3 while continuously winding it up. Heating and vapor deposition of the base film 3 is performed on the main roll 4. This main roll 4 is JI8BO6
Processed to the surface roughness standard of 59-508. Using this roll, Co--Cr and B protective films were deposited on a long polyimide tape (manufactured by Dapon Co., Ltd., trade name: Kapton H type). The deposition conditions were a roll surface temperature of 250°C and a Co-Cr deposition rate! 2,000λ/S,
The winding speed was 2 m/min, and the Cr concentration was 21w.
A Co--Cr film having a thickness of 0.3 μm and a thickness of 0.3 μm was deposited.

Further, on the surface of this Co-Cr film, the roll surface temperature 2
50°C, deposition rate 130λ/S, winding speed 2m/min
Then, a B protective film having a thickness of 200λ was formed to form Sample 1.

This sample was punched out to a size of 3 mm, and its magnetic properties were measured using a sample vibrating magnetometer. The magnetic field was applied in both directions and in a direction perpendicular to the surface, and the saturation magnetization in degrees, squareness ratio, and coercive force were determined from the M-H curve.

The results are shown in Table 1.

Further, after punching out a sample in the shape of a flexible disk from a long film and applying a liquid lubricant, a sliding test was conducted using a magnetic head with a spherical tip having a radius of curvature of 30 mm. At that time, the pressing load was 18 g, the peripheral speed of the medium was 2 m/8, and the total number of rotations until the initial reproduction output decreased to a level of 80% was defined as the sliding strength of the membrane.

Example 2゜Surface roughness was JISBO659-50O8 and 1, respectively.
Two types of main rolls with a finish of No. 28 were produced, and two types of elongated samples each consisting of a Co-Cr film and a B protective film were produced under the same conditions as in Example 1.

Sample 2.5 was prepared using a main roll with a surface roughness of 128.
A sample prepared using a 00S main roll was designated as Sample 3, and the magnetic properties of each were measured and a sliding test was conducted under the same conditions as in Example 1. The results are shown in Table 1 above.

Example 3 A main roll with a surface roughness of JI8B0659-1008 was manufactured, and Co-Cr film and B
A long sample consisting of a protective film was prepared. This sample was designated as Sample 4, and magnetic properties and sliding tests were conducted under the same conditions as Example 1. Comparative Example Conventional surface finish accuracy: 0. Using the main roll of IS, a long sample consisting of a Co--Cr film and a B protective film was prepared under the same conditions as in Example 1, and designated as Sample 5.

The magnetic properties and sliding strength of this sample were prepared under the same conditions as in Example 1.

Table 1 shows the measurement results of each Keyaki characteristic for the above Examples and Comparative Examples.0 Comparing the magnetic properties of Samples 1 to 4 produced according to the present invention and Comparative Example, it is found that in Samples 1 to 4, the magnetic properties are It can be seen that the zero coercive force and squareness ratio measured by applying an @ field are improved, and that the medium exhibits excellent characteristics as a perpendicular magnetic recording medium. Furthermore, when comparing the surface properties of the samples, it was found that in the sample prepared according to the present invention, the rough surface of the roll quickly diffused the gas generated during film heating, and the gas was trapped between the roll and the back surface of the tape. It can be seen that the pock-like irregularities on the surface caused by scratches have been reduced or completely eliminated.However, in sample 3, the roll surface was made too rough, so the shape of the roll surface was slightly transferred. Comparing the number of movements, the comparative example with the best roll surface accuracy has the weakest film strength, and as the roll surface becomes rougher, the sliding strength increases, and the roll surface roughness ranges from 50S (sample 1) to 5008 (sample 1). 3)
A similar effect can be obtained even if the surface of the roll is covered with a net. Examples thereof are shown below.

Example 4 The surface finishing accuracy of the main roll was 0 and IS, the same as in the comparative example, and stainless steel 3 (10 mesh, so
Alternatively, a 50 mesh wire mesh was tightly fixed. B under exactly the same conditions as Example 1 except that this roll was used.
A Co-Cr elongated sample with a protective film was prepared. 3
A sample made using a 00 mesh wire mesh was designated as 6. A sample prepared using a 50 mesh wire mesh was designated as 7, and magnetic custom measurements and sliding tests were conducted under the same conditions as in Example 1.

Example 5 The surface finish accuracy of the main roll was 0 and IS as in the comparative example.
The surface of this roll was covered with glass wool of 500 mesh, and a long sample was prepared under the same conditions as in Example 1, and its magnetic properties were measured and a sliding test was conducted.

Table 2 shows the measurement results of various characteristics for the above Example 4.5 and the above-mentioned Comparative Example.

As shown in Table 2, even with the method of covering the roll surface with a mesh, the coercive force in the direction perpendicular to the sample surface and the squareness ratio were improved compared to the comparative example, and the magnetic strength was also improved. I understand that. It can also be seen that the pock-like irregularities on the surface of the sample are reduced, and the same effect as in the example in which the surface of the roll is roughened is achieved.

〔Effect of the invention〕

As is clear from the above examples, in the method of continuously winding and vapor depositing while heating the main roll, the surface finish of the main roll is made as smooth as possible compared to the conventional method and equipment. Better results can be obtained by making it moderately rough. As a method for roughening the surface, it is preferable to process the surface of the roll itself to make it rough, or to cover the surface of the roll with a net. At this time, when performing surface processing, good magnetic properties and film strength can be obtained with a surface roughness in the range of 128 to 5008, but if the film properties after vapor deposition are taken into consideration, it is more preferable. Degree t from 508 to 100S
It is desirable to set ζ. Also, when using a net,
If you use a net that is about 50 mesh to 500 mesh,
The same effect as when the surface of the roll is made rough can be obtained. In this example, vacuum evaporation of Co-Cr and B was taken as an example, but the present invention also applies to sputtering method. Needless to say, it is effective when implemented.

[Brief explanation of the drawing]

FIG. 1 is a schematic side sectional view of a continuous winding vacuum deposition apparatus. 1...Film unwinder-12...Fill winder+, 3...Base film, 4...Main roll, 5...E/B electron gun, 6...Shutter, 7...
・First country of vapor deposition source

Claims (1)

[Scope of Claims] 1. A means for continuously winding a long film in a vacuum apparatus, a means for applying a magnetic recording medium to the surface of the film by a physical thin film forming method, and a means for controlling the temperature of the film. 1. A magnetic recording medium manufacturing apparatus comprising a roll for adjusting the magnetic recording medium, wherein a space is partially provided between the film and the roll. 2. The magnetic recording medium manufacturing apparatus according to claim 1, wherein the partial space is formed by roughening the surface of the roll. 3. The apparatus for manufacturing a magnetic recording medium according to claim 1, wherein the partial space covers the surface of the roll with a mesh.