JPS59172165A - Method and device for producing magnetic recording medium - Google Patents

Abstract

PURPOSE:To lessen pinholes and drop-out by segmenting and separating the space from the vapor source for a ferromagnetic material in a vacuum chamber to a part for depositing the ferromagnetic material by evaporation on a substrate supported and moved by a device for moving and supporting the substrate by means of a block chamber, attaching metallic foil or metallic screen on the inside wall in the block chamber and performing vacuum deposition in the compact block chamber. CONSTITUTION:A substrate 4 such as a polyester film is supported and moved by a device A for moving and supporting the substrate. The space from a vapor source 9 for a ferromagnetic material to a part for depositing by evaporation the ferromagnetic material on the substrate 4 moving along the circumferential side face of a cylindrical can 3 is segmented and separated by means of side walls 13 and 14, and a metallic screen or metallic foil 15 is attached on the inside wall of the chamber 12. The vapor of a ferromagnetic material 10 which is set in the source 9 and is heated to evaporate by the heating with a thermion source 11 is made incident diagonally to the substrate by the effect of an antisticking plate 16 and is deposited by evaporation on the substrate. The greater part of the ferromagnetic material failing to be deposited by evarporation on the substrate 4 is stuck on the metallic foil 15 attached on the inside wall in the block chamber 12. The ferromagnetic material failing to be deposited by evaporation is thus easily recovered and the sticking of the ferromagnetic material in the form of dust on the substrate is obviated and the generation of the pinholes and drop-out occurring in such dust is thoroughly suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a magnetic recording medium having a ferromagnetic metal thin film layer as a recording layer, and an apparatus used for carrying out the method.

Magnetic recording media with a ferromagnetic metal thin film layer as the recording layer are usually produced by heating and evaporating the ferromagnetic material in a ferromagnetic material evaporation source placed in a vacuum chamber, and using this vapor to move the substrate placed in the vacuum chamber. It is produced by vacuum deposition onto a substrate such as a polyester film that is moved by a support device.

However, with conventionally used vacuum evaporation equipment,
Only a very small amount of the ferromagnetic material heated and evaporated by the ferromagnetic material evaporation source is effectively vacuum-deposited onto the substrate that is moved by the substrate moving support device, and most of the remaining part is involved in the formation of the ferromagnetic metal thin film layer. The ferromagnetic material that adheres to the inner wall of the vacuum evaporator without any
The ferromagnetic material that was scraped off from inside the vacuum evaporation equipment was collected, but the ferromagnetic material that was swept away during this collection became dust and remained inside the vacuum evaporation equipment, which caused the vacuum evaporation equipment to be used again to remove the ferromagnetic material. When vapor deposition is performed, there is a problem in that the ferromagnetic material, which has turned into dust, adheres to the substrate and tends to cause pinholes and dropouts.

This invention was made as a result of various studies to overcome such problems, and is a space extending from a ferromagnetic material evaporation source in a vacuum chamber to a ferromagnetic material evaporation part of a substrate that is moved while being supported by a substrate moving support device. A compartment is provided to divide this space into sections, and metal foil or metal mesh is attached to the inner wall of this compartment, and the vapor flow of the ferromagnetic material is applied to the substrate being moved by the substrate moving support device within the compartment. The intended purpose was achieved by directing the person to the target.

According to this invention, the space from the ferromagnetic material evaporation source in the vacuum chamber to the ferromagnetic material evaporation portion of the substrate that is moved while being supported by the substrate movement support device is partitioned and separated by the compartment, and the space in the compartment is separated. Vacuum deposition is carried out in this compact compartment with metal foil or metal mesh attached to the inner wall, so most of the material other than the ferromagnetic material that is deposited on the substrate that is heated and evaporated by the ferromagnetic material evaporation source is metal foil. Alternatively, the ferromagnetic material may be attached to a metal mesh, so that the ferromagnetic material can be easily recovered by removing and processing the metal foil or metal mesh. In addition, unlike conventional methods, the ferromagnetic material does not adhere to the entire inner wall of the vacuum evaporator, and the ferromagnetic material that adheres to the inner wall of the vacuum evaporator does not become dust and remain inside the vacuum evaporator. Even when vacuum evaporation is performed using a vacuum evaporation apparatus, ferromagnetic material in the form of dust does not adhere to the substrate, and pinholes and dropouts caused by this are sufficiently suppressed. Therefore,
According to the method and apparatus of the present invention, a ferromagnetic metal thin film magnetic recording medium with significantly fewer pinholes and dropouts than conventional methods can be obtained.

The present invention will be described below with reference to the drawings.

Figure 1 shows a cross-sectional view of the vacuum evaporation apparatus,
is a vacuum chamber, and the inside of this vacuum chamber 1 is maintained in a vacuum by an exhaust system 2. 3 is a cylindrical can disposed in the center of the vacuum chamber 1, and a substrate 4 such as a polyester film is moved along the circumferential side of the cylindrical can 3 from a raw roll 5 via a guide roller 6. , and is wound onto a winding roll 8 via a guide roller 7. The substrate 4 is supported and moved by the substrate moving and supporting device A configured in this way. 9 is a vacuum chamber 1 facing the substrate moving support device A.
It is a ferromagnetic material evaporation source located at the bottom of the
0 is set in the ferromagnetic material evaporation source 9, and is heated and evaporated by the thermionic source 11. I2 is a compartment formed by dividing a space from the ferromagnetic material evaporation source 9 to the ferromagnetic material evaporation portion of the substrate 4 moving along the circumferential side of the cylindrical can 3 with side walls 13 and 14; A metal foil 15 is attached to the inner wall of this compartment 12. Thus, the vapor of the ferromagnetic material IO set in the ferromagnetic material evaporation source 9 and heated and evaporated by the heating of the thermionic source 11 is obliquely evaporated by the action of the deposition prevention plate 16, and most of the vapor that is not deposited on the substrate 4 is The ferromagnetic material is a metal 'M' attached to the inner wall of the compartment 12.
15. After the deposition, the metal foil 15 with a large amount of ferromagnetic material attached thereto is removed from the apparatus together with the compartment 12, and further removed from the compartment 12 outside the system, and then melted and separated by any appropriate known means. Most of the ferromagnetic material not deposited is recovered. As such metal foil 15, a material that does not easily release vapor during vapor deposition at high temperatures is preferably used, and for example, nickel foil or the like is preferably used. Further, instead of this metal foil 15, a metal net may be attached to the inner wall of the compartment 12. Even when a metal net is used, a large amount of ferromagnetic material is attached as in the case of metal foil, and after vapor deposition, Similarly, it is removed from the apparatus together with the compartment, and further removed from the compartment and recovered outside the system. At this time, simply by removing the metal mesh from the inner wall of the compartment, the ferromagnetic material adhering to the inner wall of the compartment can be easily peeled off. As such a metal mesh, a metal mesh made of nickel is preferably used as described above, and copper, iron, molybdenum, aluminum, etc. are also suitably used.

As described above, the ferromagnetic material evaporation source 9 and the ferromagnetic material evaporation portion of the substrate 4 that moves along the circumferential surface of the cylindrical can 3 are separated by the compartment 12 equipped with metal foil or metal mesh. Since vacuum deposition is performed within this compact compartment 12, the ferromagnetic material that does not participate in the deposition can be easily recovered as described above, and the ferromagnetic material is not deposited on the entire inner wall of the vacuum deposition apparatus as in the conventional method. The ferromagnetic material that adheres to the inner wall of the vacuum evaporation equipment does not become dust and remain inside the vacuum evaporation equipment, so even if this vacuum evaporation equipment is used again for vacuum evaporation, it will not remain on the substrate. There is no adhesion of ferromagnetic material in the form of dust, and pinholes and dropouts caused by this are sufficiently suppressed. Therefore, according to the method and apparatus of the present invention, a ferromagnetic metal thin film magnetic recording medium with significantly fewer pinholes and dropouts can be obtained than with conventional methods. In addition, since the compartments provided in the vacuum evaporation equipment mentioned above are removable, it is easier to recover ferromagnetic materials that do not participate in the evaporation process. preferable.

Ferromagnetic metal thin l! ! i! The ferromagnetic materials forming the layer include elemental metals such as cobalt, nickel, and iron, as well as alloys or oxides of these metals, Co-P, and C.

-Ni-P and other ferromagnetic materials commonly used for vacuum deposition are suitable, and the substrates include plastic films made of commonly used polymer moldings such as polyester, polyimide, and polyamide, and copper. A metal film made of non-magnetic metal is used.

Next, embodiments of the invention will be described.

Example 1 Using the vacuum evaporation apparatus shown in FIG. It was set so as to be wound onto a take-up roll 8 via a roller 7, and a cobalt-nickel alloy (weight ratio 8:2) 10 was set in a ferromagnetic material evaporation source 9. Next, the inside of the vacuum chamber 1 is evacuated to approximately 5×10' Torr using the exhaust system 2, and the cobalt-nickel alloy 10 in the ferromagnetic material evaporation source 9 is heated and evaporated using the thermionic source 11 to perform vacuum deposition, thereby forming a polyester base. A magnetic recording medium was fabricated by forming a ferromagnetic metal thin film layer of cobalt-nickel alloy with a thickness of 1000 mm on film 4.

Comparative Example 1 A magnetic recording medium was produced in the same manner as in Example 1, except that instead of the vacuum evaporation device shown in FIG. 1, a vacuum evaporation device without compartments as shown in FIG. 2 was used. .

Regarding the magnetic recording media obtained in Examples and Comparative Examples,
Inspected for pinholes and dropouts.

The table below shows the results.

As is clear from the above table, the magnetic recording medium obtained by the conventional method (Comparative Example 1) has pinholes and a relatively large number of dropouts, whereas the magnetic recording medium obtained by the method and apparatus of the present invention has a relatively large number of dropouts. The produced magnetic recording medium (Example 1) had few dropouts (no pinholes were observed). Therefore, according to the manufacturing method and apparatus of the present invention, a magnetic recording medium with very few pinholes and dropouts could be produced. I can see what I'm getting.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing an example of a vacuum evaporation apparatus used to carry out the manufacturing method of the present invention, and FIG. 2 is a schematic sectional view showing an example of a conventional vacuum evaporation apparatus. Patent applicant Hitachi Maxell Ltd. Figure 1

Claims (1)

[Claims] 1. In a vacuum evaporation apparatus in which a substrate moving and supporting device and a ferromagnetic material evaporation source facing the substrate moving and supporting device are disposed in a vacuum chamber, the substrate is supported by the substrate moving and supporting device from the ferromagnetic material evaporating source. A compartment is provided to separate the space leading to the ferromagnetic material deposition part of the moving substrate, and metal foil or metal mesh is attached to the inner wall of the compartment, and the vapor flow of the ferromagnetic material is directed to the substrate moving support device within this compartment. A method for producing a magnetic recording medium characterized by forming a ferromagnetic metal thin film layer on a substrate toward a supported and moving substrate, 2, a substrate moving and supporting device in a vacuum chamber, and the substrate moving and supporting device. The ferromagnetic material evaporation sources facing each other are disposed, and a compartment is provided in the space extending from the ferromagnetic material evaporation source to the ferromagnetic material evaporation part of the substrate that is moved supported by the substrate moving support device, for partitioning and separating this space. At the same time, a metal foil or a metal mesh is attached to the inner wall of this compartment, and a vapor flow of a ferromagnetic material is directed within this compartment to a substrate that is being moved while being supported by a substrate moving support device. Recording media manufacturing equipment