JPH0416854B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to an apparatus for producing a magnetic recording medium, such as a magnetic tape, by depositing a metal magnetic layer on a support. BACKGROUND TECHNOLOGY AND PROBLEMS Conventionally, there has been a magnetic recording medium manufacturing apparatus that manufactures magnetic tape capable of high-density recording, and a magnetic recording medium that can manufacture highly durable magnetic tape with the adhesive force and wear resistance of a metal magnetic layer. A media manufacturing device has been proposed. First, manufacturing equipment that can manufacture magnetic tapes capable of high-density recording is based on non-magnetic supports such as 12 μm.
A manufacturing apparatus has been proposed that uses a so-called oblique deposition method to obtain a magnetic tape by depositing a magnetic material such as cobalt from a predetermined angle oblique to the deposition surface of a thick polyethylene terephthalate film.
When this oblique vapor deposition manufacturing device is used, a metal magnetic layer of magnetic powder with a good acicular ratio is formed, and the coercive force Hc of the manufactured magnetic tape increases.
It is known that since short wavelength signals can be recorded, magnetic tapes capable of high-density recording can be manufactured. In addition, as a manufacturing device that can manufacture highly durable magnetic tapes, a metal magnetic layer, such as a cobalt layer, is formed as a two-layer structure, and the surface on which the evaporation is deposited is ion bombarded before each cobalt layer is evaporated. A manufacturing device that employs a process has been proposed. This manufacturing equipment includes a cylindrical cooling can with a built-in cooling means to prevent the non-magnetic support from elongating, molten cobalt, its crucible,
Electron guns and the like are required for each process. By combining the elements of these two devices and using a device that incorporates the diagonal evaporation method of the former for the second layer of cobalt, we manufacture a magnetic tape that is capable of high-density recording and is highly durable. What was done was done. However, just to manufacture a highly durable magnetic tape, it is necessary to wrap a non-magnetic support around two cooling cans, heat the crucible with two electron guns, and evaporate the molten cobalt. As a result, the configuration of the manufacturing equipment has become extremely complex, the manufacturing process has become complicated, and manufacturing efficiency has deteriorated. Therefore, there has been a need to create a manufacturing apparatus with a simple configuration that can manufacture magnetic tapes that are capable of high-density recording and at the same time are highly durable. OBJECTS OF THE INVENTION In view of the above points, it is an object of the present invention to provide a magnetic recording medium manufacturing apparatus that can efficiently manufacture a durable, high-performance magnetic tape in a continuous process that allows high-density recording. Summary of the Invention An apparatus for manufacturing a magnetic recording medium of the present invention includes first and second rotation cans provided close to each other, a support body running on the first rotation can and then on the second rotation can, and a support body traveling on the first rotation can and then on the second rotation can. The running direction is changed to the first rotation can and the second rotation can.
A predetermined deposition source is placed on the support on the first rotary can using the same vapor deposition source provided in opposite directions near the first and second rotary cans and at an asymmetric position with respect to the first and second rotary cans. In this system, an underlayer with a thickness of This allows for efficient manufacturing. Embodiment Hereinafter, an embodiment of the magnetic recording medium manufacturing apparatus of the present invention will be described with reference to FIG. In FIG. 1, reference numeral 1 designates the magnetic recording medium manufacturing apparatus of this embodiment as a whole, and the inside 1a of this magnetic recording medium manufacturing apparatus 1 is designed to have an atmosphere of, for example, 5×10 ^-5 Torr using a vacuum pump 2. Make it. 3 indicates a cylindrical first cooling can which rotates around a non-magnetic support 4, such as a polyethylene terephthalate film, wrapped around it for a predetermined length. Make it rotate at a predetermined speed.
Nonmagnetic supports 4 are sequentially supplied to the cooling can 3 via guide rollers 5a. Then, until the non-magnetic support 4 is once removed from the cooling can 3 via the guide roller 5b, the non-magnetic support 4 is placed in the cooling can 3 with the deposition surface facing outward.
It's like wrapping it around. Further, 6 indicates a second cooling can provided close to the first cooling can 3, and this second cooling can 6 is configured to rotate in the direction of arrow B around a rotating shaft 6a. Then, the guide rollers 5c, 5d, 5 follow the guide roller 5b.
The nonmagnetic support 4 guided in the order of e is guided by the guide roller 5f for a predetermined length until it separates from the second cooling can 6, with the vapor deposition surface outside.
As if wrapped around the cooling canister 6. Further, 7 indicates molten cobalt as a metal magnetic material for vapor deposition, and this molten cobalt 7 is put into a crucible 8. Although not shown, when the crucible 8 is heated with an electron beam from an electron gun to a predetermined level, the cobalt 7 is evaporated and ejected in predetermined amounts. Reference numeral 9 denotes a vapor deposition area defining mask that limits the traveling angle of the cobalt 7 that evaporates and flies out to a predetermined range to define the vapor deposition area of the nonmagnetic support. At the same time that the vapor deposition area for the can 3 is defined, the vapor deposition area for the second cooling can 6 is also defined. In this case, on the first cooling can 3, a first
As a layer, as shown in FIG. 4, the second cobalt vapor deposition layer 11 is formed by oblique vapor deposition to a thickness of, for example, 900 Å.
A defined range by the vapor deposition region defining mask 9 is determined so as to be sufficient for formation. here,
For oblique deposition, the second cooling can 6
The evaporation range is limited so that the incident angle θ, which is the angle between the normal direction of the point P on the outer circumference of the horizontal cross section and the direction in which the cobalt 7 flies, is, for example, 30°, and Vapor deposition should produce sufficient anisotropy in the longitudinal direction. In this example, in order to easily obtain such an incident angle, the crucible 8 is shifted toward the second cooling can 6 that performs oblique vapor deposition, as shown in FIG. Further, 12, 13, 14, and 15 indicate ion guns for activating the surface of the nonmagnetic support 4 before depositing the first cobalt vapor deposition layer 10 in the first cooling can 3, and these ion guns The surface of the non-magnetic support 4 is activated by ion bombardment by 12, 13, 14 and 15, and the first layer of cobalt is easily deposited on the non-magnetic support 4 on the first cooling can 3. Become. Further, reference numerals 16, 17, 18, and 19 indicate ion guns that emit oxygen ions, which are arranged at predetermined positions around the first cooling can 3 and the second cooling can 6, respectively.
7, 18, and 19 to oxidize the first layer of cobalt deposited by ion bombardment to increase its adhesion strength and activate the surface of the first layer of cobalt. Facilitates vapor deposition. Further, 20, 21, 22, and 23 indicate ion guns that emit oxygen ions, which are arranged at predetermined positions around the second cooling can 6, respectively, and the ion bombardment of these ion guns 20, 21, 22, and 23 causes the second cooling to be carried out. Oxidize the second layer 11 of cobalt obliquely deposited on the can 6,
It increases the adhesive strength and prevents rust. still,
The other parts are configured in the same manner as the conventional magnetic recording medium manufacturing apparatus. In this embodiment configured in this way, the first and second cooling cans 3 and 6 rotate in the direction of arrow A and the direction of arrow B, respectively, and the crucible 8 containing the molten cobalt 7 is moved toward the electron gun. The cobalt 7 is heated by the beam and evaporated into the interior 1a of the manufacturing apparatus, which is evacuated to a vacuum of, for example, 10 ^-5 Torr by the vacuum pump 2. And this cobalt 7
is a non-magnetic support 4 using a vapor deposition area defining mask 9.
Since the deposition area for the non-magnetic support 4 on the first cooling can 3 is defined, the base layer is deposited on a predetermined area of the non-magnetic support 4 on the first cooling can 3, and the base layer is deposited on the non-magnetic support 4 on the second cooling can 6. The predetermined area is diagonally deposited. On the other hand, the non-magnetic support 4 passes through an arcuate travel path while being in close contact with the side surface of the first cooling can 3 after being guided by the guide roller 5 until being guided by the guide roller 5b. During this travel route, first the ion gun 1
The nonmagnetic support 4 is sequentially ion bombarded by 2, 13, 14, and 15 to activate the surface of the nonmagnetic support 4, and then cobalt is deposited to form a 300 Å underlayer 10 as shown in FIG. Ru. and,
The surface of the non-magnetic support 4 is activated by the ion guns 16 and 17 that emit oxygen ions, making it easier to deposit the second layer of cobalt.
is oxidized, and the adhesion strength of the underlayer 10 to the non-magnetic support 4 is increased. Then, guide roller 5
b, 5c, 5d, and 5e, and passes along an arcuate travel path while closely contacting the side surface of the second cooling can 6 until it is guided by the guide rollers 5f. During this traveling route, first, ions are bombarded sequentially by ion guns 18 and 19;
The underlayer 10 on the non-magnetic support 4 is activated, making it easier to deposit the second layer of cobalt, and is oxidized to increase adhesion strength. Next, the cobalt 7 that has jumped out is deposited obliquely within a predetermined angle of incidence, forming a second layer of cobalt deposited layer 11 with a thickness of 900 Å.
is formed. Here, regarding the traveling direction of the non-magnetic support 4, the first cooling can 3 and the second
Since the cooling cans 6 are arranged close to each other and rotating, the molten cobalt 7 placed in one crucible 8 is heated by the electron beam of one electron gun, and the lower part of the first cooling can 3 is heated by the electron beam of one electron gun. The vapor deposition of the geological layer 10 and the second cobalt vapor deposition layer 11 on the second cooling can 6 side are simultaneously formed in a continuous process. Next, after this second cobalt vapor deposition layer 11 is formed, ion bombardment is performed in sequence by ion guns 20, 21, 22, and 23 to increase adhesion strength and prevent surface rust. Through these steps, a magnetic metal layer made of cobalt is formed on the nonmagnetic support 4, and a magnetic tape is manufactured. Incidentally, the magnetic tape manufactured according to this example had a coercive force Hc of 1000 Oe, a saturation magnetic flux density B _S of 9000 Gauss, and a squareness ratio of 0.85, as shown in Table 1. In order to check the durability, the magnetic layer was rubbed with a cotton swab impregnated with ethyl alcohol under a pressure of 30 to 50 kg/cm ² , and the number of times it took until the magnetic layer peeled off was 50 times. On the other hand, in 5×10 ^-5 tor
In a comparative example in which a magnetic layer of cobalt was formed to a thickness of 1000 Å on a nonmagnetic support of a 12μ layer of polyethylene terephthalate film by oblique evaporation at an angle of incidence of 45°, the coercive force Hc was as shown in Table 1.
900 Oe, the saturation magnetic flux density B _S was 10,000 Gauss, the squareness ratio was 0.85, and the number of times until the magnetic layer peeled off was 10.

[Table] As described above, this embodiment has the advantage that a high-performance magnetic tape with high coercive force, capable of high-density recording, and excellent durability can be efficiently manufactured in a continuous process. Furthermore, since the first cobalt vapor deposition layer as the base layer 10 and the second cobalt vapor deposition layer 11 can be formed at the same time using cobalt 6 placed in one crucible 8, the configuration of the manufacturing apparatus is simplified. There is profit. Furthermore, although polyethylene terephthalate was used as the material for the nonmagnetic support in the above embodiments, polyesters such as polyethylene naphthalate, polyamides, polyimides, polyethylene, or polyolefins such as polypropylene may also be used. Further, although cobalt was used as the metal magnetic material to be deposited in the above embodiment, a cobalt-nickel alloy (10 to 40 atomic percent of nickel) may also be used. Furthermore, the vapor deposition in the above embodiments is not limited to an atmosphere of 5×10 ^-5 Torr, but can also be carried out in a high vacuum, and can also be carried out by introducing a small amount of oxygen into the vapor deposition region. . Further, the vapor deposition area defining mask 9 in the above-described embodiment may be provided with an intermediate portion 9a so as to limit the cobalt that jumps out to the intermediate portion between the first cooling can 3 and the second cooling can 6. Further, the thickness of the first cobalt layer, which was set to 300 Å in the above embodiment, may be configured to be in the range of 100 to 300 Å. Here, if the thickness is 300 Å or more, the ion bombardment effect cannot be expected. Further, the thickness of the second cobalt layer, which is set to 900 Å, can be configured within a range of 500 to 1500 Å.
Here, if this thickness is too thin, it will not be possible to obtain sufficient magnetic flux, and on the other hand, if it is too thick, the coercive force will be reduced.
Hc becomes unable to rise sufficiently. It goes without saying that the present invention is not limited to the above-described embodiments, and that various other configurations can be adopted without departing from the gist of the present invention. Effects of the Invention As described above, according to the magnetic recording medium manufacturing apparatus of the present invention, a high-performance magnetic tape that is capable of high-density recording and is durable can be efficiently manufactured in a continuous process.

[Brief explanation of drawings]

FIG. 1 is a top view of an embodiment of the apparatus for manufacturing a magnetic recording medium of the present invention, FIG. 2 is a sectional view showing an example of the magnetic tape manufactured in the example shown in FIG. 1, and FIG. FIG. 7 is a diagram showing another example of a mask. 3 and 6 are first and second cooling cans;
4 is a non-magnetic support, 7 is cobalt, 8 is a crucible, 9
is a mask for defining a vapor deposition area, and θ is an incident angle.

Claims (1)

[Claims] 1 Providing first and second rotation cans in close proximity;
The support is connected to the first rotary can and then to the second rotary can.
The support body is caused to run on a rotating can, and the running direction of the support is set to be opposite to each other in the vicinity where the first rotating can and the second rotating can are close to each other, with respect to the first and second rotating cans. Using the same deposition source located at asymmetrical positions, a base layer of a predetermined thickness is deposited on the support on the first rotary can, and a base layer of a predetermined angle of incidence is deposited on the second rotary can. 1. An apparatus for manufacturing a magnetic recording medium, characterized in that a magnetic layer is deposited over a range of areas.