JPH06240443A - Device for producing thin film in vacuum and production of magnetic recording medium using the same - Google Patents

Abstract

PURPOSE:To prevent the deformation of a running system as well as a fitting pedestal even when a vacuum vessel is evacuated, to produce a high quality thin film medium and to enhance production yield. CONSTITUTION:When a fitting pedestal 16 mounted with a thin film forming means with an upper running system composed essentially of a sending roll 3 and a cooling can 5 is disposed in a vacuum vessel 1, opposite two faces, e.g. outer faces 16a, 16b of the pedestal 16 are exposed to the air or the pedestal 16 is fitted to the vacuum vessel 1 through an elastic member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum thin film manufacturing apparatus for manufacturing a thin film medium such as a vapor deposition tape and a magnetic recording medium manufacturing method using the same.

[0002]

2. Description of the Related Art A thin film medium in which a ferromagnetic metal thin film is formed by directly depositing a magnetic material such as metal or Co--Ni alloy on a non-magnetic support has a coercive force, a squareness ratio and an electromagnetic wave in a short wavelength range. It has excellent conversion characteristics, the magnetic layer can be made thin, and the thickness loss during recording demagnetization and reproduction is extremely small, or because the magnetic layer does not contain a binder that is a non-magnetic material, it is magnetic. For example, the packing density of materials can be increased.
It has a number of advantages.

In the production of the above-mentioned thin film medium, the vacuum vapor deposition method is usually adopted from the viewpoint of suitability for mass production, and the oblique vapor deposition method capable of increasing the squareness ratio in the longitudinal direction is widely used. .

An example of the vacuum thin film manufacturing apparatus to which the oblique deposition method as described above is applied is the apparatus shown in FIG. In this vacuum thin film manufacturing apparatus, the vacuum tank 1 is evacuated from two exhaust ports 15 provided at the bottom and the inside thereof is in a vacuum state, and is rotated at a constant speed in a clockwise direction indicated by an arrow a in the figure. Feed roll 3, cooling can 5, which rotates at a constant speed in the clockwise direction indicated by arrow c in the figure, and arrow b in the figure
A winding roll 4 which rotates at a constant speed in the clockwise direction indicated by is provided so that the tape-shaped non-magnetic support 2 may sequentially run from the feed roll 3 on the peripheral surface of the cooling can 5 and the winding roll 4. Has been done. The feed roll 3,
The take-up roll 4 and the cooling can 5 each have a cylindrical shape having a length substantially the same as the width of the nonmagnetic support 2.

Further, a predetermined tension is applied to the non-magnetic support 2 between the feed roll 3 and the cooling can 5 and between the cooling can 5 and the take-up roll 4 to support the non-magnetic support. Guide rolls 6 and 7 are provided at three locations, respectively, for smoothly moving the body 2.
That is, three guide rolls 6a, 6b, 6c are provided between the feed roll 3 and the cooling can 5, and three guide rolls 7a, 7b, 7b are also provided between the cooling can 5 and the winding roll 4. 7c will be provided. Therefore,
The feed roll 3, the guide roll 6, the cooling can 5, the guide roll 7, and the take-up roll 4 constitute a traveling system of the non-magnetic support 2.

Further, in the vacuum chamber 1, a crucible 8 filled with a metallic magnetic material 9 is provided below the cooling can 5, and the metallic magnetic material 9 is provided on a side wall of the vacuum chamber 1. It is heated and evaporated by the electron gun 10, and is deposited and formed as a magnetic layer on the non-magnetic support 2 that runs at a constant speed on the peripheral surface of the cooling can 5.

[0007]

However, when a thin film medium is manufactured by the vacuum thin film manufacturing apparatus as described above,
Wrinkles are likely to occur on the medium surface, reducing the product quality,
There is a problem that the manufacturing yield is reduced.

As described above, in the above vacuum thin film manufacturing apparatus, the feed roll 3, the cooling can 5, the winding roll 4, and the guide rolls 6 and 7 constitute a traveling system of the non-magnetic support 2. Each of these rolls is supported by a support provided on a mounting base arranged in the vacuum chamber.

That is, in a so-called vertical type vacuum thin film manufacturing apparatus as shown in FIG. 9, a casing-like mounting pedestal 26 having a hollow inside 26a is provided so as to seal the bottom of the vacuum chamber 1. The feed roll 3, the cooling can 5, the winding roll 4, the guide rolls 6, 7 (in FIG. 9, the feed rolls are provided on the pair of supports 27, 28 arranged in parallel on the mounting base 26 so as to face each other and are parallel to each other. 3, cooling can 5 only) are rotatably supported.

Further, in the so-called horizontal type vacuum thin film manufacturing apparatus as shown in FIG. 10, a housing-like mounting pedestal 26 having a hollow inside 26a is provided so as to seal the side wall of the vacuum chamber 1. Support 37 on this mounting base 26
Is provided vertically, and is supported by the supporting column 37 and is provided on a support 38 provided in parallel with the mounting base 26, the feed roll 3, the cooling can 5, the winding roll 4, the guide rolls 6, 7 (in FIG. 10). In the figure, only the feed roll 3 and the cooling can 5 are shown) rotatably supported.

That is, for example, when the mounting base 26 is arranged at the bottom of the vacuum chamber 1 as in the vertical vacuum thin film manufacturing apparatus shown in FIG. 9, the mounting base 26 also serves as a part of the vacuum chamber 1. become. Therefore, when the vacuum chamber 1 is evacuated,
As shown in FIG. 11, an atmospheric pressure P ₁₁ from the head and atmospheric pressures P ₁₂ and P ₁₃ from the side surfaces are applied to the vacuum chamber 1. on the other hand,
The mounting pedestal 26 is subjected to the atmospheric pressure P ₁₄ from the bottom and the atmospheric pressures P ₁₅ and P ₁₆ from the side surfaces. Then, the support body mounting surface 26b of the mounting base 26 facing the inside of the vacuum chamber 1a is distorted and curved as shown in the figure by the pressure difference between the atmosphere and the vacuum, whereby the support body 27 supporting each roll, 28 is also curved, and the feed roll 3 and the cooling can 5 assembled accurately in the atmosphere are deformed.

The above phenomenon similarly occurs in the horizontal vacuum thin film manufacturing apparatus shown in FIG. In the horizontal vacuum thin film manufacturing apparatus, the mounting base 26 is arranged on the side wall of the vacuum chamber 1, and the mounting base 26 is mounted on the vacuum chamber 1.
Will also serve as a part of. Therefore, when the vacuum chamber 1 is evacuated, the atmospheric pressure P ₂₂ from the head, the atmospheric pressure P ₂₁ from the side surface, and the atmospheric pressure P ₂₃ from the bottom are applied to the vacuum chamber 1 as shown in FIG. On the other hand, the mounting base 26 receives an atmospheric pressure P ₂₅ from the head, an atmospheric pressure P ₂₄ from the side surface, and an atmospheric pressure P ₂₆ from the bottom. Then, the supporting body installation surface 26b of the mounting pedestal 26 facing the inside of the vacuum chamber 1a is distorted and curved as shown in the figure due to the pressure difference between the atmosphere and the vacuum, and thus is provided on the supporting body installation surface 26b. The column 37 and the support 38 that supports each roll are also curved, and the feed roll 3 and the cooling can 5 assembled accurately in the atmosphere are deformed.

In such a state, when the non-magnetic support 2 is run as described above to manufacture a thin film medium, it is difficult to smoothly run the non-magnetic support 2 by these deformed rolls. Therefore, wrinkles are generated on the surface of the non-magnetic support 2, and as a result, wrinkles are also generated on the surface of the thin film medium on which the magnetic layer is formed, which deteriorates the quality of the product and decreases the manufacturing yield.

As a solution for solving the above problem, it is considered that the mounting base 26 is made thick to increase its mechanical strength to prevent the distortion due to the atmospheric pressure. However, there is an inconvenience that the vacuum chamber becomes large and heavy.

It is also conceivable to incorporate a wrinkle removing roll made of rubber into the running system of the non-magnetic support to extend wrinkles by applying tension in the width direction to the non-magnetic support. For example, as shown in FIG. 13, the traveling system of the non-magnetic support 2 of the vacuum thin film manufacturing apparatus having a configuration substantially similar to that of the vacuum thin film manufacturing apparatus shown in FIG. 1 is slightly modified, and this traveling system is made of rubber. The wrinkle removing rolls 11 and 12 may be incorporated.
Note that, in the vacuum thin film manufacturing apparatus shown in FIG. 13, the description of the portions overlapping the vacuum thin film manufacturing apparatus shown in FIG. 1 will be omitted.

That is, as shown in FIG. 13, there are two guide rolls 6 between the feed rolls 3 and the cooling cans 5, only the guide rolls 6b and 6c, and between the feed rolls 3 and the guide rolls 6b and the guide rolls 6b and 6b. Rubber wrinkle removing rolls 11a and 11b are respectively provided between 6c, and there are two guide rolls 7 between the cooling can 5 and the winding roll 4, only the guide rolls 7a and 7b.
Rubber wrinkle removing rolls 12a and 12b are also provided between b and between the guide roll 7b and the winding roll 4, respectively.

However, in this method, the traveling system is complicated, dust is attached to the wrinkle removing rolls 11 and 12, rubber is dropped from the wrinkle removing rolls 11 and 12, and gas is generated from the rubber of the wrinkle removing rolls 11 and 12. This is not preferable because it causes inconveniences such as deterioration of the degree of vacuum due to the release of the. In addition, dust attached to the wrinkle removing rolls 11 and 12 and wrinkle removing rolls 11 and 12
The rubber dropped from 12 adheres to or scratches the non-magnetic support 2 running on it, causing dropout of the thin film medium to be produced, resulting in deterioration of the characteristics of the thin film medium.

Therefore, the present invention has been proposed in view of the conventional circumstances, and provides a vacuum thin film manufacturing apparatus which is small in size and light in weight and does not transmit strain due to atmospheric pressure to the thin film forming means constituting the traveling system. It is an object of the present invention to provide a method of manufacturing a magnetic recording medium having excellent characteristics by using this.

[0019]

In order to achieve the above object, the first invention of the present application provides a traveling system in which a mounting base is arranged in a vacuum chamber and a plurality of rolls are mounted on the mounting base. In the vacuum thin film manufacturing apparatus provided with the thin film forming means, it is characterized in that the two opposite surfaces of the mounting pedestal are exposed to the atmosphere.

A second invention of the present application is a vacuum thin film manufacturing method in which a mounting base is arranged in a vacuum chamber, and a thin film forming means having a traveling system constituted by a plurality of rolls is provided on the mounting base. In the apparatus, the mounting base is attached to the vacuum chamber via an elastic member.

A third invention of the present application is a method of manufacturing a magnetic recording medium, wherein the above-mentioned vacuum thin film manufacturing apparatus is used to run a non-magnetic support without disposing a rubber wrinkle removing roll in the running system. It is characterized in that a metal magnetic thin film is formed.

[0022]

In the first aspect of the present invention, the two opposing surfaces of the mounting pedestal, which is arranged in the vacuum chamber and provided with the thin film forming means having the traveling system constituted by a plurality of rolls, are exposed to the atmosphere. Therefore, when the inside of the vacuum chamber is in a vacuum state, the atmospheric pressures are applied to the two surfaces of the mounting pedestal which face each other, but these atmospheric pressures are canceled out by each other. Therefore, the mounting base is not distorted. As a result, no strain is transmitted to the thin film forming means having the traveling system constituted by the plurality of rolls provided on the mounting base.

In the second invention of the present application, the mounting pedestal provided in the vacuum chamber with the thin film forming means having a traveling system constituted by a plurality of rolls has an elastic member for the vacuum chamber. When the inside of the vacuum chamber is in a vacuum state, the atmospheric pressure applied to the vacuum chamber is absorbed by the elastic member and is not transmitted to the mounting pedestal. Therefore, the strain is not transmitted to the thin film forming means having the traveling system constituted by the plurality of rolls provided on the mounting base.

On the other hand, in the above vacuum thin film manufacturing apparatus, since the strain is not transmitted to the thin film forming means, the wrinkle removing roll made of rubber is unnecessary. Therefore, in the method for producing a magnetic recording medium of the present invention in which a nonmagnetic support is run without disposing a rubber wrinkle removing roll in the running system by using the above vacuum thin film manufacturing apparatus, and a magnetic recording medium of the present invention is formed, Does not adhere to the surface of the metal magnetic thin film, and the degree of vacuum is not deteriorated or scratched.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments to which the present invention is applied will be described below with reference to the drawings. In this example,
This is an example of a so-called vertical vacuum thin film manufacturing apparatus.

As shown in FIG. 1, the vacuum thin film manufacturing apparatus of the present embodiment has a vacuum chamber 1 in which the inside is brought into a vacuum state by being exhausted from two exhaust ports 15 provided at the bottom. Similarly to the feed roll 3 which rotates at a constant speed in the clockwise direction indicated by the middle arrow a, and a winding roll 4 which rotates at a constant speed in the clockwise direction indicated by an arrow b are provided. The tape-shaped non-magnetic support 2 is designed to run sequentially.

A cooling can 5 having a diameter larger than that of each of the rolls 3 and 4 is provided in the middle of the non-magnetic support 2 traveling from the feed roll 3 to the take-up roll 4 side. There is. The cooling can 5 is provided so as to pull out the non-magnetic support 2 to the left in the figure, and is also adapted to rotate at a constant speed in the clockwise direction indicated by an arrow c in the figure. The feed roll 3, the take-up roll 4, and the cooling can 5 each have a cylindrical shape having a length substantially the same as the width of the nonmagnetic support 2.
Is provided with a cooling device (not shown) inside so that deformation of the non-magnetic support 2 due to temperature rise can be suppressed.

Therefore, the non-magnetic support 2 is sequentially fed from the feed roll 3, passes through the peripheral surface of the cooling can 5, and is wound up by the winding roll 4. Three guide rolls 6 and 7 are provided between the feed roll 3 and the cooling can 5 and between the cooling can 5 and the take-up roll 4, respectively.
By these guide rolls 6 and 7, the feeding roll 3 to the cooling can 5 and the cooling can 5 to the winding roll 4
A predetermined tension is applied to the non-magnetic support 2 that runs over the non-magnetic support 2 so that the non-magnetic support 2 runs smoothly. That is, three guide rolls 6a, 6b, 6c are provided between the feed roll 3 and the cooling can 5, and three guide rolls 7a, 7b, 7b are also provided between the cooling can 5 and the winding roll 4. 7c will be provided. Therefore, the feed roll 3, the guide roll 6, the cooling can 5, the guide roll 7, and the winding roll 4 constitute a traveling system of the non-magnetic support 2.

A crucible 8 is provided below the cooling can 5 in the vacuum chamber 1, and a metal magnetic material 9 is filled in the crucible 8. The crucible 8 is formed as a container having substantially the same length as the roll length of the cooling can 5.

On the other hand, an electron gun 10 for heating and evaporating the metallic magnetic material 9 filled in the crucible 8 is attached to the side wall of the vacuum chamber 1. This electron gun 1
0 is arranged at a position such that the electron beam X emitted from the electron gun 10 irradiates the metallic magnetic material 9 in the crucible 8. The metallic magnetic material 9 evaporated by the electron gun 10 is deposited and formed as a magnetic layer on the non-magnetic support 2 that runs at a constant speed on the peripheral surface of the cooling can 5.

A shutter 13 is provided between the cooling can 5 and the crucible 8 and near the cooling can 5.
Is provided. The shutter 13 is formed so as to cover a predetermined region of the non-magnetic support 2 that runs at a constant speed on the peripheral surface of the cooling can 5. The metallic magnetic material 9 evaporated by the shutter 13 is obliquely deposited on the non-magnetic support 2 within a predetermined angle range. Further, during such vapor deposition, oxygen gas is supplied to the surface of the non-magnetic support 2 through an oxygen gas inlet 14 provided penetrating the bottom of the vacuum chamber 1 to provide magnetic properties, durability and weather resistance. Is being improved.

By the way, as shown in FIG. 2, the feed roll 3 and the take-up roll 4 which are the thin film forming means constituting the traveling system are all mounted in the vacuum chamber 1 as shown in FIG.
It is provided above. The mounting base 16 is a vacuum chamber 1
Is formed as a support base in the shape of a plane rectangle that is large enough to be placed inside, and its four sides are outer surfaces 16a,
16b (the remaining two outer surfaces are not shown) is attached to the vacuum chamber 1 so as to be exposed to the atmosphere. In other words, the mounting pedestal 16 is such that only the four outer sides 16a and 16b of the mounting pedestal 16 are exposed to the atmosphere.
It is attached to the vacuum chamber 1. Therefore, the outer surfaces 16a and 16b of the mounting base 16 form a part of the vacuum chamber 1. A seal member made of a rubber seal or the like having excellent airtightness is provided at the joint between the mounting base 16 and the vacuum chamber 1 in order to maintain the degree of vacuum in the vacuum chamber 1.

The mounting pedestal 16 is provided with a pair of supports 17a and 17b for supporting the rolls 3, 4, ... 7 and the cooling can 5. These supporting members 17a and 17b are provided perpendicularly to the mounting base 16 so as to be substantially parallel to each other with a predetermined space therebetween, and between the supporting members 17a and 17b, the rolls 3, 4 ... 7 and the cooling can 5 ( Only the feed roll 3 and the cooling can 5 are shown in the figure) so as to be rotatable. That is, each of the rolls 3, 4, ... 7 and the cooling can 5
Is rotated about the axis by supporting both ends of the rotary shaft by the supports 17a and 17b, respectively.

Further, the mounting pedestal 16 is provided on the surface opposite to the surface on which the rolls 3, 4, ... 7 and the cooling can 5 are provided, on the surface opposite to the rolls 3, 4 ,. A plurality of reinforcing members 18 such as bridge girders are provided vertically and horizontally at predetermined intervals to support the mounting base 16 from the bottom so as to prevent it from being bent by the weight of 5 and increase the mechanical strength of the mounting base 16. As a result, the pair of supports 1
The rolls 3, 4, ... 7 and the cooling can 5, which are rotatably supported by 7a and 17b, are assembled with high accuracy in the atmospheric state without the rotation shaft being bent. Note that these reinforcing members 18 do not come into contact with the vacuum chamber 1.

The vacuum thin film manufacturing apparatus configured as described above
When the vacuum chamber 1 is in a vacuum state, as shown in FIG.
In addition, the vacuum chamber 1 has an atmospheric pressure P from the head.₁And large from the side
Barometric pressure P ₂, P₃And atmospheric pressure P from the bottom_FourIt costs
The vacuum chamber 1 is deformed as shown in FIG. Meanwhile, the mounting base
The seat 16 has outer surfaces 16a and 16b exposed to the atmosphere.
Atmospheric pressure P_Five, P₆Takes. However, this
Atmospheric pressure P on mounting base 16_Five, P₆Hit each other
The areas are exposed to each other, and the area exposed to the atmosphere is the same.
Since the pressure is the same because they are the same, they are offset.
It As a result, the mounting base 16 is not distorted by atmospheric pressure.
It does not occur and the mounting base 16 does not deform.

Therefore, the distortion due to the atmospheric pressure is not transmitted to the supports 17a and 17b arranged on the mounting pedestal 16, and the rolls 3, 4 ... 7 and the cooling can 5 supported thereby are also distorted. Does not occur. As a result, wrinkles do not occur on the non-magnetic support 2 run by the rolls 3, 4 ... 7 and the cooling can 5, and wrinkles also occur on the surface of the thin film medium obtained by vapor deposition of the magnetic layer. No
A thin film medium having good quality can be manufactured with high yield.

Further, as a result, it is not necessary to dispose a wrinkle removing roll or the like in the traveling system of the non-magnetic support, and the structure of the vacuum thin film manufacturing apparatus can be simplified. Further, the vacuum chamber and the exhaust system can be downsized by simplifying the device.

Furthermore, since it is not necessary to dispose a wrinkle removing roll in the running system of the non-magnetic support, the rubber is removed from the wrinkle removing roll, and the degree of vacuum is reduced due to the release of gas from the rubber of the wrinkle removing roll. Inconvenience such as deterioration does not occur. In addition, dust adhered to the wrinkle removing roll or rubber dropped from the wrinkle removing roll does not adhere to the non-magnetic support running on it or scratch it, and the dropout of the thin film medium to be produced. Does not occur and the characteristics do not deteriorate.

In the above embodiment, the mounting pedestal 16
Although a part of the above is a part of the vacuum chamber 1, for example, the mounting pedestal 16 may be completely arranged in the vacuum chamber 1. That is, as shown in FIG. 4, the vacuum chamber 1 having a housing shape is placed on the floor surface 23, and the pair of support members 17 are provided inside the vacuum tank 1.
7 and a cooling can 5 (only the feed roll 3 and the cooling can 5 are shown in the drawing) are rotatably supported by a mounting base 16.

At this time, the mounting base 16 is attached to the vacuum chamber 1
As shown in FIG. 5, an opening 26 is provided in the bottom plate portion 1a of the vacuum chamber 1 so as to support it so as not to come into contact therewith, and a plurality of columnar or prismatic leg portions 20 are exposed from the opening 26, for example. The mounting base 16 is supported on the floor surface 23 by these legs 20. Further, an elastic member 22 made of a rubber seal or the like is interposed between the leg portion 20 and the opening 26 to absorb strain of the vacuum chamber 1 due to atmospheric pressure when the vacuum chamber 1 is in a vacuum state. In other words, an elastic member 22 that maintains the airtight state of the vacuum chamber 1 and absorbs the strain of the vacuum chamber 1 due to the atmospheric pressure is provided at the joint 24 between the leg 20 supporting the mounting base 16 and the vacuum chamber 1. Set up.

In addition to this, as shown in FIG.
A bellows-shaped metal seal (bellows) that surrounds the leg 20 between the mounting base 16 and the bottom plate 1a of the vacuum chamber 1 which is the joint 24 between the leg 20 supporting the vacuum chamber 6 and the vacuum chamber 1. You may make it interpose the elastic member 25 which consists of etc.

With this structure, as shown in FIG. 7, when the vacuum chamber 1 is in a vacuum state, the atmospheric pressure P ₁ from the head, the atmospheric pressures P ₂ and P ₃ from the side surface, and the bottom portion. Although the vacuum chamber 1 is deformed as shown in the figure by the atmospheric pressure P ₄ from the above, the strain generated in the vacuum chamber 1 causes the elastic member 22 interposed between the leg portion 20 and the vacuum chamber 1. Is absorbed by the mounting portion 16 and the strain is not transmitted to the legs 20.
No distortion is transmitted. Further, when a rubber seal is used as the elastic member 22, the degree of airtightness of the vacuum chamber 1 can be increased and the degree of vacuum can be increased. Similarly,
Even if a metal seal is arranged between the vacuum chamber 1 and the mounting base 16, no strain is transmitted to the mounting base 16.

Therefore, the distortion due to the atmospheric pressure is not transmitted to the supports 17a and 17b arranged on the mounting pedestal 16, and the rolls 3, 4 ... 7 and the cooling can 5 supported thereby are also distorted. Does not occur. As a result, wrinkles do not occur on the non-magnetic support 2 run by the rolls 3, 4, ... 7 and the cooling can 5, and wrinkles occur on the surface of the thin film medium obtained by vapor deposition of the magnetic layer. No
A thin film medium having good quality can be manufactured with high yield.

Further, as a result, it is not necessary to dispose a wrinkle removing roll or the like in the traveling system of the non-magnetic support, and the structure of the vacuum thin film manufacturing apparatus can be simplified. Further, the vacuum chamber and the exhaust system can be downsized by simplifying the device.

Furthermore, since it is not necessary to dispose a wrinkle removing roll in the traveling system of the non-magnetic support, the rubber is removed from the wrinkle removing roll, and the degree of vacuum is reduced due to the release of gas from the rubber of the wrinkle removing roll. Inconvenience such as deterioration does not occur. In addition, dust adhered to the wrinkle removing roll or rubber dropped from the wrinkle removing roll does not adhere to the non-magnetic support running on it or scratch it, and the dropout of the thin film medium to be produced. Does not occur and the characteristics do not deteriorate.

In this embodiment, the example of the vertical vacuum thin film manufacturing apparatus has been described so far, but it is needless to say that similar effects can be expected in the horizontal vacuum thin film manufacturing apparatus.

In this embodiment, a vacuum thin film manufacturing apparatus is provided with a mounting base 16 arranged in the vacuum chamber 1, and a thin film forming means having a traveling system constituted by a plurality of rolls is provided on the mounting base 16. However, the idea of the present invention can be applied to an apparatus in which a device requiring high assembly accuracy is provided on the mounting pedestal 16 arranged in the vacuum chamber 1, and when the vacuum chamber is in a vacuum state. Even in the
Does not impair the ability of the installed equipment.

Next, in order to confirm the effect of the vacuum thin film manufacturing apparatus of this example, a thin film medium was manufactured using this, and the characteristics of the above thin film medium were evaluated.

That is, using the vacuum thin film manufacturing apparatus of this embodiment as shown in FIGS. 1 and 2 and the conventional vacuum thin film manufacturing apparatus as shown in FIG. 13, sample tapes each having a width of 8 mm are manufactured. Was measured for dropout.

The sample tape was manufactured as follows. First, a magnetic layer was formed on a non-magnetic support by vapor deposition. At this time, as the non-magnetic support, a polyethylene terephthalate film having a thickness of 10 μm and a width of 150 mm formed with a water-soluble latex containing acrylic ester as a main component (a density of 10 million pieces / mm ² ) as an undercoat layer is used. did. On the other hand, Co ₈₀ —Ni ₂₀ wt% was used as the metallic magnetic material forming the magnetic layer. The deposition conditions for the magnetic layer are as follows: the incident angle of the metallic magnetic material is 40 to 90 °, the running speed of the non-magnetic support is 0.17 m / sec, and the thickness of the magnetic layer to be formed is 0. 2 μm and the amount of oxygen introduced is 3.3 × 10 ⁻⁶ m ³ /
sec, and the degree of vacuum during vapor deposition was 7.0 × 10 ^-2 Pa.

Next, a back coat and a top coat were formed on the non-magnetic support on which the magnetic layer was formed and slit into a width of 8 mm to obtain a sample tape. The back coat was formed by applying a mixture of carbon and urethane binder to a thickness of 0.6 μm, and the top coat was formed by applying perfluoropolyether.
The sample tape manufactured using the vacuum thin film manufacturing apparatus of this example is referred to as a working sample tape, and the sample tape manufactured using the conventional vacuum thin film manufacturing apparatus is referred to as a comparative sample tape.

Then, the dropout of each sample tape formed as described above was measured as follows. That is, the recording wavelength λ = 8 mm video deck
Modified to record / reproduce at a single frequency of 0.50 μm, record on each sample tape at the above recording wavelength with the 8 mm video deck, envelope-detect the reproduced output waveform, and drop the signal (drop). Out) was counted by a dropout counter.

Whether or not it is a dropout is determined by the time t of the dropout portion in the waveform and its depth d in the waveform measured by envelope detection as shown in FIG. However, the depth d is a value determined by the measured depth a of the dropout portion in the figure and the depth b of the waveform, and d = −20 log (b / a) dB
Stipulated as. Then, those having a depth d of -16 dB or less and a time t of 10 µsec or more were designated as dropout 1, and those having a depth d of -10 dB or less and a time t of 10 µsec or more were designated as dropout 2, and the numbers thereof were measured. The results are shown in Table 1.

[0054]

[Table 1]

As is clear from the results shown in Table 1, the number of dropouts in the practical sample tape is smaller than that in the comparative sample tape. This is because in the implementation sample tape, the rubber thin wrinkle removing roll is not arranged in the vacuum thin film manufacturing apparatus, and the dust adhering to the wrinkle removing roll and the rubber dropped from the wrinkle removing roll run on it. This is probably because it does not adhere to or scratch the non-magnetic support. Therefore, it was confirmed that a thin film medium having excellent characteristics can be manufactured by using the vacuum thin film manufacturing apparatus of this example.

[0056]

As is apparent from the above description, according to the present invention, a mounting base is arranged in a vacuum chamber, and a thin film forming means having a traveling system constituted by a plurality of rolls is provided on the mounting base. In the vacuum thin film manufacturing equipment
Since the two opposite surfaces of the mounting pedestal are exposed to the atmosphere, atmospheric pressure is applied to the mounting pedestal only from the two opposite surfaces when the vacuum chamber is evacuated, and these atmospheric pressures are mutually different. They cancel each other out because they work in the direction of canceling each other. Therefore, the mounting pedestal is not distorted, the traveling system is not distorted, and a thin film medium of good quality can be manufactured, and the manufacturing yield can be improved.

The present invention also provides a vacuum thin film manufacturing apparatus, wherein a mounting base is arranged in a vacuum chamber, and a thin film forming means having a traveling system constituted by a plurality of rolls is provided on the mounting base. Since the mounting pedestal is attached to the joint of the vacuum chamber via the elastic member, the atmospheric pressure applied to the vacuum chamber is not absorbed by the elastic member and transmitted to the mounting pedestal when the vacuum chamber is in a vacuum state. . Therefore, the mounting pedestal is not distorted, the traveling system is not distorted, and a thin film medium of good quality can be manufactured, and the manufacturing yield can be improved.

Further, in the vacuum thin film manufacturing apparatus of the present invention, it is not necessary to increase the thickness of the mounting pedestal or to dispose the wrinkle removing roll in the traveling system as in the conventional case, and the structure of the vacuum thin film manufacturing apparatus is improved. Can be simplified. Furthermore, the vacuum chamber and the exhaust system can be downsized by simplifying the device, and its industrial value is very high.

Furthermore, using the vacuum thin film manufacturing apparatus of the present invention, a method for manufacturing a magnetic recording medium in which a metal magnetic thin film is formed by running a non-magnetic support without disposing a rubber wrinkle removing roll in the running system. In the above, since it is not necessary to dispose a wrinkle removing roll in the traveling system of the non-magnetic support, there are inconveniences such as the loss of the constituent material of the wrinkle removing roll, for example, the loss of the rubber and the deterioration of the degree of vacuum due to the release of gas from the rubber. Does not occur.
In addition, dust adhered to the wrinkle removing roll or rubber dropped from the wrinkle removing roll does not adhere to the non-magnetic support running on it or scratch it, and the dropout of the thin film medium to be produced. Does not occur and the characteristics do not deteriorate.

[Brief description of drawings]

FIG. 1 is a schematic view of a main part of a vacuum thin film manufacturing apparatus.

FIG. 2 is a schematic cross-sectional view of a main part schematically showing an example of a vacuum thin film manufacturing apparatus to which the present invention is applied.

FIG. 3 is a schematic cross-sectional view of a main part schematically showing an example of a state in which a vacuum tank of a vacuum thin film manufacturing apparatus to which the present invention is applied is in a vacuum state.

FIG. 4 is a schematic cross-sectional view of a main part schematically showing another example of the vacuum thin film manufacturing apparatus to which the present invention is applied.

FIG. 5 is an enlarged sectional view of an essential part schematically showing an example of a joint between a vacuum chamber and a leg of a vacuum thin film manufacturing apparatus to which the present invention is applied.

FIG. 6 is an enlarged cross-sectional view of a main part schematically showing another example of the joining portion between the vacuum tank and the leg portion of the vacuum thin film manufacturing apparatus to which the present invention is applied.

FIG. 7 is a schematic cross-sectional view of essential parts schematically showing another example of a state in which the vacuum tank of the vacuum thin film manufacturing apparatus to which the present invention is applied is in a vacuum state.

FIG. 8 is a diagram showing a relationship between a waveform measured by envelope detection and a dropout portion in the waveform.

FIG. 9 is a schematic cross-sectional view of a main part schematically showing a conventional vertical vacuum thin film manufacturing apparatus.

FIG. 10 is a schematic cross-sectional view of a main part schematically showing a conventional horizontal vacuum thin film manufacturing apparatus.

FIG. 11 is a schematic cross-sectional view of essential parts schematically showing a state in which a vacuum tank of a conventional vertical vacuum thin film manufacturing apparatus is in a vacuum state.

FIG. 12 is a schematic cross-sectional view of a main part schematically showing a state in which a vacuum tank of a conventional horizontal vacuum thin film manufacturing apparatus is in a vacuum state.

FIG. 13 is a schematic view of a main part of a conventional vacuum thin film manufacturing apparatus.

[Explanation of symbols]

 1 ... Vacuum tank 3 ... Feed roll 4 ... Winding roll 5 ... Cooling can 6,7 ... Guide roll 11, 12 ... Wrinkle removing roll 16 ... Mounting base 17 ... ..Support 18 ... Reinforcing member 20 ... Legs 22, 25 ... Elastic member

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Makoto Shimanuki 6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation

Claims (3)

[Claims] 1. A vacuum thin film manufacturing apparatus comprising a mounting base arranged in a vacuum chamber, and a thin film forming means having a traveling system constituted by a plurality of rolls provided on the mounting base. A vacuum thin film manufacturing apparatus characterized in that two facing surfaces are exposed to the atmosphere. 2. A vacuum thin film manufacturing apparatus comprising a mounting base arranged in a vacuum chamber, and a thin film forming means having a traveling system constituted by a plurality of rolls provided on the mounting base. A vacuum thin film manufacturing apparatus, which is attached to a vacuum chamber via an elastic member. 3. The vacuum thin film manufacturing apparatus according to claim 1 or 2, wherein a non-magnetic support is allowed to run without disposing a rubber wrinkle removing roll in a running system to form a metal magnetic thin film. And a method for manufacturing a magnetic recording medium.