JPH0262725A - Apparatus for producing magnetic tape - Google Patents

Abstract

PURPOSE:To obtain the perpendicular magnetic recording medium having excellent electromagnetic conversion characteristics by providing magnets near the aperture of a deposition preventive plate which regulates a thin magnetic film forming region and inclining the direction of the magnetic field in the aperture of the deposition preventive plate with the transporting direction of a high-polymer film. CONSTITUTION:The magnets 21 installed near the aperture 12 of the deposition preventive plate 11 are so disposed that the direction of the magnetic fields 22 generated from the magnets 21 incline by (90 deg.+theta) with the transporting direction 16 of the high- polymer film 2. The magnetic anisotropy of the soft magnetic layer is induced by the magnetic fields 22 and the soft magnetic layer the easy axis of which is faces the (90 deg.+theta) direction and the difficult axis faces the theta direction with the transporting direction 16 of the high-polymer film is obtd. The traveling direction of a magnetic head and the difficult axis direction of the soft magnetic layer coincide if the perpendicular magnetic recording medium produced in such a manner is worked to a tape shape and is used for a perpendicular magnetic tape. The recording and reproducing sensitivity is enhanced and the electromagnetic conversion characteristics are improved in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for manufacturing a perpendicular magnetic recording medium.

In recent years, as the density of magnetic recording has increased, research has been actively conducted on perpendicular magnetic recording media capable of high-density recording.

As shown in FIG. 3, this perpendicular magnetic recording medium 1 has five
A soft magnetic layer 3 of permalloy or the like is placed on a long polymer film 2 with a thickness of about 0 μm, and a magnetically anisotropic layer of Co-Cr alloy etc. A perpendicular recording layer 4 having a magnetic field is continuously formed to a thickness of about 0.2 μm using methods such as vapor deposition, sputtering, plating, etc.

The soft magnetic layer 3 serves to concentrate magnetic flux from the magnetic head and the perpendicular recording layer during recording and reproduction, and has the effect of increasing recording and reproduction sensitivity.

Such a perpendicular magnetic recording medium 1 is used after being processed into a disk or tape depending on the recording/reproducing apparatus. In particular, perpendicular magnetic tapes processed into tapes have a high storage capacity and are therefore of high value for use in video tapes that can provide high image quality.

[Conventional technology]

A conventional manufacturing apparatus of this type using the sputtering method is shown in FIG. The polymer film 2 wound around the unwinding roll 6 in the vacuum chamber 5 is transported along the outer peripheral surface of the can 7 and taken up onto the winding roll 8. At this time, a sputtering phenomenon is caused with respect to the target 9.10, which has the same composition as the soft magnetic layer 3 and the perpendicular recording layer 4, which are placed parallel to the can 7. The recording layer 4 is formed continuously. In this way, the perpendicular magnetic recording medium 1 is manufactured.

A deposition prevention plate 11 is installed between the can 7 and the targets 9 and 10, and is provided with openings 12 and 13 that define a magnetic thin film forming area. That is, the adhesion prevention plate 11 is for preventing the formation of an unnecessary magnetic thin film. target 9.10
2, in order to increase the film formation speed of the soft magnetic layer 3 and perpendicular magnetic layer 4 formed on the polymer film 2 and to make the film thickness distribution uniform, as shown in FIGS. 5 and 6, A rectangular magnetron target is placed. Arrow 15 is the direction of the magnetic field generated from the magnetron target, and arrow 16 is the direction of conveyance of the polymer film 2.

Perpendicular magnetic recording media 1 manufactured continuously in this way
Since the magnetic anisotropy of the soft magnetic layer 3 is induced by the magnetic field 15 generated by the magnetron target, its easy axis direction is directed to the transport direction 16 of the polymer film 2, and the hard axis direction is directed to the right angle direction. .

By the way, some video tape recorders and digital audio recorders employ a helical scan method, as shown in FIG.

In that case, the magnetic head 17 provided in the cylinder 30 runs obliquely to the running direction 19 of the magnetic tape 18 .

31 is a tape guide post.

On the other hand, the recording track 20 is formed at an angle of .theta. with respect to the running direction 19 of the magnetic tape 18, as shown in FIG.

The relationship between recording density and reproduction output in this case is shown in FIG.

Furthermore, in the perpendicular magnetic recording medium 1, the relationship between the direction of magnetic anisotropy in the soft magnetic layer 3 and the running direction of the magnetic head 17 is such that in the difficult axis direction, the reproduction output is maximum and the medium noise is minimum.
It is known that in the easy axis direction, the reproduction output is minimum and the medium noise is maximum.

[Problem to be solved by the invention]

However, when the perpendicular magnetic recording medium 1 manufactured in this way is used for a perpendicular magnetic tape, the magnetic head 17
The running direction 21 of the soft magnetic layer 3 is at (90°−
θ), there was a drawback that the electromagnetic conversion characteristics were inferior.

Therefore, an object of the present invention is to provide a manufacturing apparatus that can manufacture a perpendicular magnetic recording medium with excellent electromagnetic conversion characteristics.

[Means to solve the problem]

According to the present invention, in a manufacturing apparatus for a magnetic recording medium that continuously forms a magnetic thin film medium on a long polymer film using a sputtering method, an opening in an adhesion prevention plate that defines a magnetic thin film forming area is provided. There is obtained a magnetic tape manufacturing apparatus characterized in that a magnet is provided near the adhesion prevention plate, and the direction of the magnetic field within the opening of the adhesion prevention plate is inclined with respect to the transport direction of the polymer film.

[Effect]

According to the magnetic tape manufacturing apparatus of the present invention, magnetic anisotropy in the magnetic layer is induced by the magnetic field generated from the magnet. That is, a magnetic layer having an easy axis in the direction of the magnetic field and a hard axis in the direction perpendicular to the direction of the magnetic field with respect to the transport direction of the polymer film is obtained.

〔Example〕

1 and 2 show a magnetic tape manufacturing apparatus according to an embodiment of the present invention. Components similar to those in FIG. 4 are designated by the same reference numerals and their explanation will be omitted.

This manufacturing apparatus includes a magnet 21 installed near the opening 12 of the adhesion prevention plate 11. The magnet 21 is installed so that the direction of the magnetic field 22 generated from the magnet 21 is inclined by (90600) with respect to the transport direction 16 of the polymer film 2. Here, two magnets 21 are placed on both sides of the opening 12.
Although they are arranged so as to be in contact with the outer surface of the adhesion prevention plate 11, they may be separated from the outer surface of the adhesion prevention plate 11.

According to this manufacturing apparatus, the soft magnetic layer 3 is
magnetic anisotropy is induced. That is, a soft magnetic layer 3 was obtained in which the easy axis was oriented in the (90''+θ) direction and the hard axis was oriented in the θ direction with respect to the transport direction 16 of the polymer film.

After processing the perpendicular magnetic recording medium produced in this way into a tape shape and using it as a perpendicular magnetic tape, the running direction of the magnetic head 17 and the difficult axis direction of the soft magnetic layer 3 coincided, so that the recording and reproducing sensitivity was improved. has increased, and the electromagnetic conversion characteristics have improved. FIG. 9 shows comparative data of the recording density characteristics of perpendicular magnetic tapes manufactured using the manufacturing apparatus according to the present invention in relation to conventional magnetic tapes.

〔Effect of the invention〕

As described above, according to the present invention, it has become possible to provide an apparatus for manufacturing a perpendicular magnetic recording medium with excellent electromagnetic conversion characteristics.

6 is an explanatory diagram of the operation of the manufacturing apparatus of FIG. 4, FIG. 7 is a perspective view showing the actual usage state of the manufactured magnetic tape, and FIG. The figure is also an explanatory diagram of the recording track, and FIG. 9 is a graph showing the effect.

1... Perpendicular recording medium, 2... Polymer film, 3.
... Soft magnetic layer, 4... Perpendicular recording layer, 7... Can,
9゜10...Target, 11...Adhesion prevention plate, 12.
13... Opening, 21... Magnet, 22... Magnetic field.

[Brief explanation of the drawing]

FIG. 1 is a front view of a manufacturing apparatus according to an embodiment of the present invention, FIG. 2 is an enlarged partial view of the manufacturing apparatus of FIG. 1 when viewed from the ■-■ direction, and FIG. 3 is a general vertical recording medium FIG. 4 is a front view of the conventional manufacturing equipment, and FIG. , IU Figure 4 Figure 7 Figure 1/ Figure 8

Claims (1)

[Claims] 1. In a magnetic recording medium manufacturing apparatus that continuously forms a magnetic thin film on a long polymer film using a sputtering method, a magnet is placed near the opening of the adhesion prevention plate that defines the magnetic thin film formation area. A magnetic tape manufacturing apparatus characterized in that the direction of the magnetic field within the opening of the adhesion prevention plate is inclined with respect to the conveyance direction of the polymer film.