JP2000057568A - Alignment device for magnetic recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an alignment device for a magnetic recording medium which is capable of easily setting the magnetic field of a magnetic field generat ing means to such a state that the magnetic field does not affect a magnetic layer and allows the reduction in a size and cost. SOLUTION: The alignment device 10 for the magnetic recording medium has guide parts 12 erected in a base part 11 and is mounted with the magnetic field generating means 13 in these guide parts 12. A base 60 having the magnetic layer of an undried state passes near the magnetic field generating means 13. The alignment device 10 is capable of setting the magnetic field of the magnetic field generating means 13 so as not to affect the magnetic layer by bringing a magnetic field direction changing means 16 consisting of a magnetic material near to the magnetic field generating means 13 at the time of not use.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for orienting a magnetic recording medium, and more particularly to a magnetic recording medium which is set so that a magnetic field generated by a magnetic field generating means does not affect a magnetic layer on a support when not in use. Related to an alignment device.

[0002]

2. Description of the Related Art Conventionally, a magnetic recording medium such as a magnetic tape or a magnetic disk is coated with a magnetic liquid formed by dispersing magnetic fine particles in a resin dissolved in an organic solvent, on a running belt-shaped non-magnetic support. Subsequently, the magnetic layer is subjected to an orientation treatment, a dry solidification treatment, and a surface treatment, and finally, the support having the magnetic layer is cut or punched out.

[0003] In the manufacturing process of a magnetic tape such as a video tape or a memory tape, an orientation treatment such as aligning magnetic fine particles in the longitudinal direction of the tape is required. As an apparatus for performing such an orientation treatment, an orientation apparatus having two permanent magnets having the same poles opposed to each other (hereinafter, referred to as a two-pole opposed magnet) is used.

On the other hand, in the process of manufacturing a magnetic disk such as a floppy disk, a so-called random orientation treatment is required to make the orientation of the magnetic fine particles irregular before the magnetic layer applied to the support solidifies. As an apparatus for performing a random orientation process, various orientation apparatuses using a permanent magnet, an electromagnet, or the like are used.

FIG. 6 is a view showing a conventional orienting device provided with a two-pole opposed magnet. The orientation device 50 includes a base 51 and a guide 52 erected on the base 51.
In the guide portion 52, a two-pole opposed magnet 53 is mounted so as to be movable along the guide portion. Guide section 5
At the upper end of 2, a gap adjusting device 55 is installed,
The two-pole opposed magnet 53 is
Is adjusted (hereinafter, referred to as a gap G) between the two permanent magnets 53a and 53b that constitute the above. Then, a roller 54 is inserted between the two-pole opposed magnets 53 whose gap G is adjusted.
Is passed by the support 60 guided by.

Various types of magnetic recording media can be manufactured on a magnetic recording medium manufacturing line in which devices for performing orientation treatment, drying solidification treatment, surface treatment and the like are arranged on a support having a magnetic layer. To do so, it is necessary to appropriately change the settings of each device. Regarding the orientation device, for example, an orientation device for a magnetic tape cannot be used for manufacturing a magnetic disk. Therefore, it is necessary to set the orientation device not used so that the magnetic field generated from the orientation device does not affect the magnetic layer of the magnetic recording medium to be manufactured at that time.

FIG. 6 shows the state of the orientation device 50 when the orientation device 50 is not used by a two-dot chain line. As described above, when the orientation device 50 is not used, the orientation device 50 is retracted from the support 60 together with the orientation device 50 so that the magnetic field of the two-pole opposed magnet 53 does not affect the magnetic layer on the support 60.

The orientation device 70 shown in FIG. 7 has a guide portion 72 longer than the guide portion 52 of the orientation device 50 shown in FIG. When the orienting device 70 is not used, the magnets 73 a and 73 b constituting the two-pole opposed magnet 73 affect the magnetic layer on the support 60 by the magnets 73 a and 73 b constituting the two-pole opposed magnet 73 as shown by a two-dot chain line in FIG. The guide portion 72 is retracted to the upper end side and the lower end side, respectively, so as not to affect

[0009]

In the orientation device 50 shown in FIG. 6, it is necessary to retreat the orientation device 50 from the support 60 when not in use. However, the weight of the orienting device is heavy, and the gap adjusting mechanism 55 that adjusts the gap G of the two-pole opposed magnet 53 composed of two permanent magnets having the same poles is opposed to each other. Thus, the orientation device 50 has a heavy structure. Therefore, the operation of retracting the orientation device 50 from the support 60 is very complicated. Further, when the orientation device 50 is retracted, the support 60 must be cut, which causes a reduction in production efficiency.

On the other hand, in the orientation device 70 shown in FIG.
Each magnet 7 is arranged such that the magnetic field intensity at the center, that is, at the position where the support 60 passes, is less than 50 Oersted (Oe).
It is said that it is preferable to retreat 3a and 73b. The interval between the support 60 and each of the retracted permanent magnets is referred to as a retreat interval R. However, in order to reduce the magnetic field strength in this way, the evacuation interval R must be very large, so that the guide portion 72 becomes long.
This is not preferable because it causes an increase in the size and cost of the orientation device 70.

The present invention has been made on the basis of the above background, and an object of the present invention is to easily set a state in which a magnetic field of a magnetic field generating means such as a magnet does not affect a magnetic layer on a support. It is an object of the present invention to provide a magnetic recording medium orientation device which can be made compact and can be reduced in cost.

[0012]

The object of the present invention is to provide a magnetic layer coated on a non-magnetic support in which the magnetic layer is disposed near a support where the magnetic layer is in an undried state. A magnetic recording medium orienting apparatus provided with a magnetic field generating means, wherein the magnetic recording medium orienting apparatus is provided with a magnetic field direction changing means made of a magnetic material and capable of approaching the magnetic field generating means. be able to.

Here, a permanent magnet or the like can be used as the magnetic field generating means. The magnetic field generating means may be arranged, for example, on both sides of the non-magnetic support, or may be arranged only on one side. As the magnetic field direction changing means, for example, a plate-like member made of a ferromagnetic material such as iron or a paramagnetic material such as aluminum can be adopted.

According to the orientation apparatus for a magnetic recording medium having such a configuration, when not in use, the direction of the magnetic field generated from the magnetic field generating means toward the support is changed by the magnetic field direction changing means. The state is set so as not to affect the magnetic layer on the body. Therefore, when the orientation device is not used, it is not necessary to retract the orientation device from the support. When the magnetic field generating means is retracted from the support, the retreat interval R can be shortened.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described in detail with reference to FIGS. In addition, about the member already demonstrated, the same code | symbol or an equivalent code | symbol is attached | subjected, and description is simplified or abbreviate | omitted. FIG. 1 is a diagram showing a first embodiment of the present invention. The orientation device 10 includes a guide portion 12 erected on a base portion 11.
Inside, a two-pole opposed magnet 13 is mounted movably along the guide portion. At the upper end of the guide section 12, a gap adjusting device 15 for adjusting the gap G is installed. The support 60 passes between the two-pole opposed magnets 13.

The guide portions 1 are located at positions on both sides of the support member 60 at appropriate distances from the support member 60.
A shield plate 16 as a magnetic field direction changing means is attached to both side surfaces (upstream and downstream of the bipolar opposing magnet 13 along the moving direction of the support body 60). Shield plate 1
Reference numeral 6 is made of a ferromagnetic material such as iron.

In the orientation device 10 having such a configuration, each of the magnets 1 constituting the two-pole opposed magnet 13 is not used when not in use.
3a and 13b are retracted to the upper end side and the lower end side of the guide portion 12, respectively. At this time, each magnet 13a, 13b
Is housed between a pair of shielding plates 16 made of a ferromagnetic material.

FIG. 2 shows the magnets 13a, 13b before the magnets 13a, 13b are retracted between the pair of shielding plates 16.
4 shows a state of a magnetic field generated from b. As shown in the figure, the magnetic field generated from the N pole of each magnet goes to the support 60 while drawing a gentle arc, and is in a direction parallel to the moving direction of the support 60 on the support 60.

FIG. 3 shows a state of a magnetic field generated from the magnet 13a when the magnets 13a and 13b are housed in the pair of shielding plates 16. As shown in the figure, at this time, the portion of the shielding plate 16 near the N pole of the magnet 13a is magnetized to the S pole. Therefore, the magnetic field generated from the N pole of the magnet 13a does not go to the support 60 but goes to the portion of the shielding plate 16 magnetized to the S pole.

According to the orientation device 10 as described above, when not in use, the magnets 13a, 1
3b is retracted to the upper end side and the lower end side of the guide portion 12, respectively, and the magnets are stored between the pair of shielding plates 16, so that the magnetic field intensity at the position where the support 60 passes can be rapidly reduced. . Therefore, the orientation device 10
According to the embodiment, the magnetic field intensity at the position where the support 60 passes can be sufficiently reduced at a retreat interval shorter than the retreat interval R in the conventional orientation device shown in FIG. The state can be easily set so as not to affect the magnetic layer on 60. Further, since the retreat interval R can be shortened, the size and cost of the orientation device 10 can be reduced.

FIG. 4 is a diagram showing a second embodiment of the present invention. The orienting device 20 includes a guide portion 22 erected on a base portion 21. In the guide portion 22, a two-pole opposed magnet 23 is mounted movably along the guide portion. The support 60 passes between the two-pole opposed magnets 23. A shielding plate 26 made of iron or the like is mounted on the side surfaces of the guide portions 12 on both sides of the support 60 so as to be movable on the side surfaces of the guide portions 12. At the upper end of the guide portion 22, the gap G is adjusted, and the shielding plate 26 is moved to adjust the distance between the support-side end of the shielding plate 26 and the support 60 (hereinafter, referred to as shielding distance S). The shield plate operating device 25 is installed.

In the orientation device 20 having such a configuration, when not in use, the shielding plate 26 is moved to the support 60 side, and the magnets 23a and 23b constituting the two-pole opposed magnet 23 are placed in the shielding plate 26. Is stored. Each magnet 23a, 23
When b is housed in the shielding plate 26, the magnetic field intensity at the center of the gap G of the two-pole opposed magnet 23, that is, at the position where the support 60 passes, sharply decreases. Therefore, even with such an orientation device 20, the size and cost of the orientation device 20 can be reduced.

[0023]

Examples of the present invention will be described below, but the present invention is not limited to these examples. (Example 1) An apparatus for orienting a magnetic recording medium having the structure of the first embodiment shown in FIG.
At the support passing position in the center of the gap G,
A rectangular neodymium magnet having a cross section of 35 mm × 35 mm, which can provide a magnetic field strength of about 4200 Oe (Oe) at the maximum, was used, and a 20 mm-thick iron plate was used as the shielding plate 16.

(Measurement of Relationship Between Gap and Magnetic Field Strength) Using Example 1, the magnetic field strength at the center of the gap when the gap G was changed was measured. Graph 1 showing the measurement results is shown in FIG. For comparison, magnets 73a and 73b have the same structure as the conventional orientation device 70 shown in FIG.
The same measurement was performed using an orientation device for a magnetic recording medium using the same material as in Example 1. Graph 1 also shows the measurement results of this comparative example.

As shown in the graph 1, the magnetic field intensity is less than 50 Oersted in Example 1 where the gap is 200 mm and does not affect the magnetic layer, whereas the comparative example is less than 50 Oersted with the gap 500 mm. became. From the measurement results, it was found that the first embodiment of the present invention can be easily set to a state in which the magnetic field does not affect the magnetic layer, and the retreat interval R can be shortened, as compared with the conventional example. . Example 1 of the present invention
Can adjust a wide range of the magnetic field strength by adjusting the gap G in a short distance, so that it can be applied to various kinds of magnetic recording media having different required magnetic field strengths.

The present invention is not limited to the above-described embodiments and examples, but can be appropriately modified or changed. For example, in the above-described embodiment, by changing the relative positions of the magnet as the magnetic field generating means and the shielding plate as the magnetic field direction changing means in the direction perpendicular to the direction of movement of the support, the magnet becomes magnetic. Although the effect on the layer has been adjusted, the relative position between the magnetic field generating means and the magnetic field direction changing means in a direction parallel to the moving direction of the support may be changed. Also, 2
The magnetic field direction changing means may be moved so that the magnetic field direction changing means is inserted between the two magnets constituting the pole opposing magnet.

In the above-described embodiment, the shielding plates are provided on both side surfaces of the guide portion (for example, on the left side surface and the right side surface of the guide portion 12 in FIG. 1), but surround the entire circumference of the guide portion. (For example, in FIG. 1, in addition to the left and right sides of the guide portion 12, a shielding plate that connects a pair of shielding plates 16 on the near side and the back side of the paper) is provided. Is also good.

[0028]

The orientation apparatus for a magnetic recording medium according to the present invention is provided with a magnetic field direction changing means for preventing a magnetic field generated from the magnetic field generating means from affecting the magnetic layer on the support. ing. Therefore, when the orientation device is not used, it is not necessary to retract the orientation device from the support, so that the setting operation of the device when not in use is greatly simplified. In addition, when the magnetic field generator is retracted from the support, the retracted distance can be shortened, so that the apparatus can be reduced in size and cost.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention.

FIG. 2 is a diagram showing a state of a magnetic field generated from a magnet in the first embodiment.

FIG. 3 is a diagram illustrating a state of a magnetic field generated from a magnet in the first embodiment.

FIG. 4 is a diagram showing a second embodiment of the present invention.

FIG. 5 is a diagram showing a measurement result according to the first embodiment of the present invention.

FIG. 6 is a diagram showing a conventional magnetic recording medium orientation device.

FIG. 7 is a view showing a conventional magnetic recording medium orientation device.

[Explanation of symbols]

 10, 20 Orienting device for magnetic recording medium 11, 21 Base 12, 22 Guide portion 13, 23 2-pole opposed magnet 14, 24 Roller 15 Gap adjusting device 16, 26 Shielding plate (magnetic field direction changing means) 25 Shielding plate operating device

Claims (1)

[Claims] 1. A magnetic recording medium comprising: a magnetic recording medium provided with a magnetic field generating means disposed in the vicinity of a support in which the magnetic layer is in an undried state in order to perform an orientation treatment on a magnetic layer applied on a nonmagnetic support. An orientation device for a magnetic recording medium, comprising: a magnetic field direction changing unit made of a magnetic material, which is close to the magnetic field generation unit.