JPH0687306B2 - Method of manufacturing magnetic recording medium - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a magnetic recording medium for high density magnetic recording, which can be magnetized in a direction perpendicular to a substrate surface.

2. Description of the Related Art In recent years, the practical application of a ferromagnetic metal thin film magnetic recording layer has been studied from the conventional coating type magnetic recording layer as a magnetic recording medium.

Along with this, the manufacturing method has been studied mainly on the vacuum deposition method suitable for forming the ferromagnetic metal thin film.

FIG. 2 is a schematic diagram of the internal configuration of a vacuum deposition apparatus used for manufacturing a magnetic recording medium using a conventional Co—O-based or Co—Ni—O-based perpendicular magnetization film as a magnetic recording layer.

In FIG. 2, 1 is a substrate such as a polymer film, 2 is a delivery shaft, 3 is a winding shaft, 4 is a rotary support, 5 is an evaporation source, 6 is a vacuum container, 7 is a shield plate, 8 is a slit, Reference numeral 9 is a gas introduction nozzle, and 10 is a vacuum pump.

Using the apparatus of FIG. 2, while introducing oxygen gas from the gas introduction nozzle 9, Co or CoNi (Ni is 5% to 30% from the evaporation source 5).
%) Is evaporated, and a part of the evaporation source is evaporated by a component which is vertically incident on the substrate 1 through the slit 8. Thus, the perpendicularly magnetized film made of Co-O or Co-Ni-O is enhanced. It can be continuously formed on a molecular film.

In terms of mass productivity, this method is superior to the sputtered perpendicular magnetization film such as Co-Cr and the Co-Cr electron beam evaporation film in which the rotary support is kept at a high temperature. Is promising as a manufacturing method.

Problems to be Solved by the Invention However, in the above-described configuration, the short wavelength recording / reproducing characteristics predicted from the magnetic characteristics of the obtained perpendicular magnetization film may not be realized. In particular, when a long medium is manufactured, the output fluctuation, which is considered to be caused by the fluctuation of the spacing loss, is large, which is a practical problem.

The present invention has been made in view of the above circumstances, and provides a method capable of stably obtaining a long medium in a state where a short wavelength output is large.

Means for Solving Problems The method for producing a magnetic recording medium of the present invention in order to solve the above problems is to move a polymer film, introduce oxygen from the vapor deposition start side, and introduce hydrogen to the vapor deposition end side, Co or Co-Ni vapor is directed vertically to the film.

Action In the method of manufacturing a magnetic recording medium of the present invention, oxygen acts to satisfy the conditions of the perpendicular magnetization film by the above-described configuration, and the oxide film on the head access side of the perpendicular magnetization film, that is, the surface side of the film is introduced. Since the thickness can be reduced based on the reducing action of hydrogen, a long medium can be manufactured with a large short wavelength output.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an internal configuration diagram of a vapor deposition apparatus used for carrying out the present invention.

In FIG. 1, 11 is a polymer film, 12 is a delivery shaft, 13 is a winding shaft, 14 is a rotary support, 15 is an evaporation source, 16 is a vacuum container, 17 is a shield plate, 18 is a slit, 19 is hydrogen. An introduction nozzle, 20 is an oxygen introduction nozzle, and 21 is a vacuum pump.

In FIG. 1, the distance from the center of the evaporation source 15 to the polymer film 11 immediately above is 34.5 cm, the diameter of the rotary support is 66 cm, the width of the slit 18 is 4 cm, the oxygen introduction nozzle 20 and the hydrogen introduction nozzle.
The effect of the present invention was confirmed in the following examples with the distance between the tips of 19 being 12 cm and the distance between the tips and the center of the evaporation source being 31 cm.

The surface temperature of the rotary support was kept constant at 25 ° C., and the gas was introduced after the degree of vacuum reached 1 × 10 ⁻⁶ (Torr) before gas introduction.

While moving a polyethylene terephthalate film with a thickness of 10 μm, a Co-O, Co-Ni-O film with a thickness of 0.2 μm is formed, and after flattening treatment, stearic acid is vacuum-deposited by about 30Å and then slitted to a width of 8 mm. Then, various magnetic tapes were made as prototypes.

For performance comparison, a ferrite ring head with a gap length of 0.16 μm was used, and a read output with a recording wavelength of 0.4 μm
10 points were selected arbitrarily from 000m, 10m at each point was measured, and the maximum and minimum output values were compared relative to each other.

The coercive force in the vertical direction was measured with a vibrating sample magnetometer.

The following table shows the comparison of manufacturing conditions and performance.

From the above, it can be clearly understood that the magnetic recording medium obtained by the present invention has a good reproduction output even in the longitudinal direction and is stable.

Although the magnetic tape has been described in this embodiment, it is possible to manufacture a magnetic disk and a magnetic sheet according to the present invention, and it is possible to manufacture a uniform and high-performance medium in a large amount.

EFFECTS OF THE INVENTION As described above, according to the present invention, it is possible to obtain an excellent effect that a large number of magnetic recording media that can be magnetized in the perpendicular direction can be produced.

[Brief description of drawings]

FIG. 1 is an internal block diagram of an example of a vapor deposition apparatus used for carrying out the method of manufacturing a magnetic recording medium of the present invention, and FIG. 2 is an internal block diagram of a conventional vapor deposition apparatus. 11 …… Polymer film, 15 …… Evaporation source, 18 …… Slit, 19 …… Hydrogen introducing nozzle, 20 …… Oxygen introducing nozzle.

Claims (1)

[Claims] 1. A magnetic recording medium, characterized in that, when Co or Co-Ni is vapor-deposited on a moving polymer film by vertical incidence, oxygen is introduced at the vapor-deposition start side and hydrogen is introduced at the vapor-deposition end side. Production method.