JPH01222050A - Manufacture of vacuum deposition apparatus and magnetic recording medium and magnetic recording medium - Google Patents

Abstract

PURPOSE:To make it possible to use an inexpensive high polymer film with low heat resistance by applying knurling work to the surface of a main roll used at the time of vapor-depositing a thin magnetic-alloy film onto the surface of a high polymer film and then coating the above main-roll surface with ceramics. CONSTITUTION:A magnetic recording medium, such as magnetic tape, is manufactured by heating and evaporating a magnetic alloy of Co-Cr, etc., from a vapor deposition source 7 by means of an electron beam from an electron gun 5 and vapor-depositing the resulting vapor onto the surface of a high polymer film 3 into a thin-film state by a vacuum vapor deposition method. At this time, the gas generated from the film 3 is easily diffused at the time of vapor deposition by applying knurling work to the surface 8 of a main roll 4 round which the high polymer film 3 is to be wound and coating the above main roll 4 surface with a ceramic layer 9 or ZrO2, etc., and a high temperature can be instantaneously maintained at the time of the vapor deposition of the thin magnetic-alloy film because the area of contact surface between the roll 4 and the film 3 is extremely small, by which the thin film of magnetic alloy can be easily formed even on an inexpensive high polymer film with low heat resistance, such as polyethylene phthalate.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to floppy disks or magnetic tapes in which a thin magnetic metal film is coated on the surface of an organic polymer film, and in particular, the present invention relates to a floppy disk or magnetic tape in which a thin magnetic metal film is coated on the surface of an organic polymer film. The present invention relates to a method for manufacturing a magnetic recording medium that allows the use of polymer films.

[Prior Art] An example of a basic continuous vapor deposition apparatus is shown in FIG. 11.6, page 310 of Vacuum Deposition (Nikkan Kogyo Shimbun, 4th edition, 1962). - It is common knowledge that the surface of the main roll, which is involved in the running and heating and cooling of the film inside the shell, is processed to have a "mirror" finish or the like in order to improve its adhesion to the film.

[Problems to be Solved by the Invention] The objective of the above-mentioned prior art is to finish the surface of the main roll with as high precision as possible to improve the thermal conductivity of the film. However, there is a problem to be solved in that the desired magnetic properties etc. cannot be obtained with this method. One way to solve this problem is to set the temperature of the main roll sufficiently high and use a highly heat-resistant film such as polyimide as the base film. However, these films are very expensive.

An object of the present invention is to replace the high heat-resistant films such as polyimide films currently used as vapor deposition substrates for perpendicular magnetic recording media in the shell with polyethylene phthalate (polyethylene phthalate), which is about one hundredth of the cost. An object of the present invention is to provide a vapor deposition method that allows the use of low heat-resistant films such as PET) films.

[Means for Solving the Problems] The above object can be achieved by knurling the surface of the main roll. More preferably, the knurling surface is coated with a ceramic material having excellent heat insulation properties, such as SiO2 or ZrO2.

[Function] FIG. 1 is a schematic diagram of a continuous winding type vapor deposition apparatus used for depositing a metal magnetic thin film or the like on a long organic polymer film. In this device, tape supply roll 1
The base film 3 fed out from the main roll 4 is heated by the main roll 4, and then a gold a thin film or the like is continuously formed on the mask opening 10, after which it is wound up by the take-up roll 2. The present invention is characterized in that the surface 8 of the main roll 4 is knurled as shown in FIG. 2, and more preferably the surface is coated with ceramic N9. Such a knurled roll (hereinafter referred to as a knurling roll) quickly diffuses gas generated when the base film is heated, particularly gas generated from the back surface of the film. This gas has an adverse effect on the magnetic properties and surface properties of the magnetic thin film, and the ease with which the gas is diffused by the knurling roll 4 has favorable results in stabilizing the magnetic properties and smoothing the surface. On the other hand, since the knurling roll 4 structurally has an extremely small contact area with the base film, and is rather close to a non-contact state, the main roll 4 and the base film 3 are semi-insulated during the formation of the vapor deposited film. Therefore,
At the moment when the deposition takes place, the film experiences high temperatures, which has favorable consequences for the magnetic properties of the Co--Cr film and also for the mechanical strength of the protective film. Furthermore, this means that even if the temperature of the main roll 4 itself is set to a low temperature, it is possible to effectively maintain a high temperature during vapor deposition, and the time during which the main roll 4 experiences high temperatures is extremely long. Since the length is short, the thermal load on the film is reduced, and even films such as polyethylene terephthalate (PET), which have low heat resistance, can be used. Further, by coating with ceramics, the above-mentioned heat insulation effect is further improved, and a film with lower heat resistance can be used.

[Example] Hereinafter, the details of the present invention will be explained with reference to examples.

Example 1 Cross-shaped knurling according to JISBO951 standard on the entire surface of the main roll 4 (module m = 0.5)
, and then using a ZrO2 set roll 4 on the surface, polyethylene phthalate (PET) with a thickness of 50 μm is coated.
Ge, Co-Cr and B films were deposited on tape 3. The deposition conditions were a laurette temperature of 110°C and a winding speed of 2.
m/min, Ge200 people, Co-Cr2
500 people.

The membranes of 200 people with the thickness of the secretory pulp were deposited. Incidentally, the Cr concentration in the magnetic material portion is 21 to 22%.

This sample was punched out to 8 mmφ, and a sample vibrating magnetometer (VS
Magnetic properties were measured using M). The magnetic field was applied in the in-plane direction and in the perpendicular direction, and the saturation magnetization, squareness ratio, and coercive force were determined from the M-H curve. Table 1 shows the results.
Shown below.

Further, a sample was punched out from a long film in the shape of a flexible disk, and after applying liquid lubricant, a sliding test was performed using a magnetic head with a spherical tip shape and a radius of curvature of 30 mm. At that time, the pressing load was 18 gr, the rotational speed of the medium was 2 m/s, and the initial playback output was 80%.
The total number of rotations required to decrease to this level was taken as the sliding strength of the membrane. The results are also shown in Table 1.

Example 2 The surface of the main roll 4 was subjected to JISBO951 cross knurling and module m=0.3 knurling, and a ZrO2 ceramic coating of 150 μm was applied thereto. A sample was prepared and evaluated under the same conditions as in Example 1. .

The results are shown in Table 1.

Example 3 The surface of the main roll 4 was subjected to JISBO951 cross knurling and module m=0.5 knurling to make the surface mechanically smooth. In this example, no ceramic coating was applied.

Using this knurling roll 4, a sample was prepared and evaluated under the same conditions as in Example 1. The results are shown in Table 1.

Comparative example 1 Main roll 4 with conventional surface finish accuracy of 0.1S (mirror finish)
A sample with the same conditions and contents as in Example 1 was prepared using
We conducted an evaluation. The results are shown in Table 1.

Comparing the magnetic properties of Examples 1 to 3 produced according to the present invention and Comparative Example 1, in Examples 1 to 3, a magnetic field is applied in a direction perpendicular to the magnetic surface for measurement. Furthermore, when comparing the surface properties of the samples, in Examples 1 to 3 produced according to the present invention, since a knurled roll was used, the gas generated when heating the base film quickly diffused, and the gas was transferred between the roller and the back of the film. It can be seen that the unevenness caused by being trapped in between is reduced or eliminated. However, depending on the tension applied to the base film during vapor deposition, the knurling pattern may be visible or invisible. On the other hand, in Comparative Example 1, an effective vapor deposition temperature was not ensured, the coercive force was low, and fine cracks and irregularities were observed throughout the metal film.

Furthermore, when comparing the number of times of sliding, Comparative Example 1, in which the main roll was mirror-finished, had extremely low film strength.

It can be seen that Examples 1 to 3 produced according to the present invention are superior. There is also a difference between Examples 1 and 2, which were coated with ceramics (ZrO2), and Example 3, which was not coated, and the improvement in the heat insulation effect by the ceramic coating was related to the further improvement in the strength of the deposited metal film. I know that there is.

[Effects of the Invention] As can be seen from Examples 1 to 3 above, in the method of continuously winding and vapor depositing while heating the main roll, the surface of the main roll is knurled and the conventional roll-film contact type Overall, better results can be obtained by using the raw egg contact type, which has sufficient heat insulation ability during vapor deposition. Above all, the effect on the substrate temperature during vapor deposition is remarkable (by the way, the method of Comparative Example 1 resulted in "magnetic properties" comparable to those of Examples 1 to 3).
To ensure that the substrate temperature A needs to be 50℃), -
It is used as a base film to maintain the substrate temperature during vapor deposition inside the shell. The economical effect of making it possible to use low heat resistant PET tape, which can be purchased at a cost of about 100% less than high heat resistant polyimide tape, is extremely significant.

Although not mentioned in the examples, polysulfone.

It goes without saying that similar effects can be obtained by using polyetherimide, polyethersulfone, polyetherketone, etc. as the base film.

[Brief explanation of the drawing]

1... Film supply roll, 2... Film winding roll, 3... Base film, 4... Main roll,
Knurling roll, 5...E/Bffi subgun, 6...
- Shutter, 7... Vapor deposition source, 8... Knurled roll surface portion, 9... Ceramic coating layer, 1
0...Mask opening.

Claims (1)

[Claims] 1. A vacuum deposition apparatus having a main roll capable of running a long film and heating or cooling the long film, the surface of the main roll being knurled. A vacuum evaporation device characterized by: 2. The vacuum evaporation apparatus according to claim 1, wherein the knurled surface of the main roll is coated with ceramics. 3. Using the vacuum evaporation apparatus according to claim 1,
A method for manufacturing a magnetic recording medium, in which a long film made of an organic polymer is heated by a main roll, and a magnetic material is continuously deposited on the surface of the long film. 4. A magnetic recording medium characterized by using a low heat-resistant organic polymer film such as polyethylene phthalate (PET), polysulfone, polyetherimide, polyethersulfone, and polyetherketone as a substrate.