JPS61278030A - Method and device for manufacturing magnetic recording medium - Google Patents

Abstract

PURPOSE:To obtain magnetic recording medium which scarcely generates drop-out and is excellent in its electromagnetic conversion characteristic, by making a surface characteristic of a guide member conform to the quality and state of a substrate which contacts to the guide member, and a ferromagnetic thin metallic film layer which is formed on the substrate. CONSTITUTION:Guide rolls 8, 10 and tension rolls 9, 12 are all formed by covering the outside peripheral surface of a metallic roll 18 with a film 19 consisting of a high polymer organic compound, are low in its hardness and soft, and conform satisfactorily to the quality and state of a substrate. Accordingly, it can be prevented effectively that the surface and the rear side of the substrate are flawed. Also, a guide roll 11 and 13 consist of a metallic roll whose surface roughness is <=0.5s, are comparatively hard, and have hardness being roughly equal as to a ferromagnetic thin metallic film layer which is formed on a substrate 6, therefore, even if said rolls contact to the ferromagnetic thin metallic film layer which has been formed on the substrate 6, the surface is not shaved by the ferromagnetic thin metallic film layer, and it does not occur, either that the ferromagnetic thin metallic film layer is flawed by its shavings. Accordingly, generation of drop-out can be suppressed satisfactorily.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] 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.

[Background technology]

A magnetic recording medium having a ferromagnetic metal thin film layer as a recording layer is usually produced by moving a substrate such as a polyester film to the circumferential side of a cylindrical can through guide members such as various guide rolls and tension rolls arranged in a vacuum chamber. The guide member is made by vacuum-depositing ferromagnetic material on this substrate, and generally has a surface roughness of IS~3S (wave height value 1μ~3μ). A relatively hard metal roll having a Vickers hardness of about 200 to 400 is used.

However, this type of metal roll that has been used in the past is harder than plastic substrates, etc., so when the substrate is guided through these guide members, it may come in contact with these guide members. Scratches are likely to occur, and many scratches occur on the front and back surfaces of the substrate, and because of this, good electromagnetic conversion characteristics cannot be obtained, and many dross bubbles occur.

[Purpose of the invention]

In view of the current situation, the present invention has been made to evaluate the surface characteristics of a guide member in a manufacturing apparatus for a magnetic recording medium having a ferromagnetic metal thin film layer as a recording layer. This was done for the purpose of providing a magnetic recording medium that is suitable for the characteristics and has excellent electromagnetic conversion characteristics with less dropout.

(Summary of the Invention) The present invention provides a magnetic recording medium manufacturing apparatus including a substrate moving support device and a ferromagnetic material supply source facing the substrate moving support device in a vacuum chamber. , a guide member whose outer peripheral surface is coated with a film made of a high-molecular organic compound, and a metal guide member with a surface roughness of 0.5s or less, the former being in contact with a traveling substrate, and the latter being formed on a traveling substrate. The ferromagnetic metal thin film layer is placed in contact with the surface of the ferromagnetic metal thin film layer.Compared to conventional metal rolls, the outer peripheral surface is coated with a polymeric organic compound that is relatively soft and compatible with the properties of the substrate. Since the substrate is always in contact with the guide member coated with the substrate, scratches and scratches on the front and back surfaces of the substrate can be effectively prevented. After the ferromagnetic metal thin film layer is formed on the substrate, the ferromagnetic metal thin film layer is always in contact with a relatively hard metal guide member with a surface roughness of 0.5s or less. The surface force of the guide member is reduced by the relatively hard ferromagnetic metal thin film layer, and the ferromagnetic metal thin film layer is not scratched by the shavings.
The guide member covered with a film made of these polymeric organic compounds and the metal guide member with a surface roughness of 0.5s or less effectively prevent scratches on the front and back surfaces of the substrate and the ferromagnetic metal thin film layer. The occurrence of dropout can be effectively suppressed.

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 interior of the vacuum chamber 1 is divided into sections by a partition plate 2, and is maintained in vacuum by exhaust systems 3 and 4, respectively.A chamber 65 is located in the center of the vacuum chamber 1 and spans over the two partitioned chambers. A substrate 6 such as a polyester film is moved along the circumferential side of the cylindrical can 5 from a raw roll 7 via a guide roll 8, a tension roll 9, and a guide roll 10. , is wound onto a winding roll 14 via a guide roll 11, a tension roll 12, and a guide roll 13.

During this time, the substrate 6 moves along the circumferential side of the cylindrical can 5.
The ferromagnetic material 16 is heated and evaporated in a ferromagnetic material evaporation source 15 disposed at the bottom of the vacuum chamber 1 facing the ferromagnetic material 16 , and this vapor flow is directed diagonally toward the substrate 6 by the action of the anti-adhesion plate 17 . Oblique incidence deposition is performed.

Here the guide roll 8.10 and the tension roll 9
．． 12, as shown in FIG. 2, the outer peripheral surface of the metal roll 18 is coated with a coating 19 made of a polymeric organic compound. Therefore, these guide rolls 8.10 and tension rolls 9.12 are all Compared to conventional metal rolls, the hardness is lower and softer, and the hardness is almost the same as the hardness of the substrate, making it well suited to the properties of the substrate. In addition, the coefficient of friction is small, and the scratches on the surface are obtuse-angled and not sharp like conventional metal rolls. Therefore, when the substrate 6 is guided by these guide rolls 8.10 and tension rolls 9.12, scratches may occur even if the front and back surfaces of the substrate come into contact with each other. It can be effectively prevented.

Further, the guide rolls 11 and 13 have a surface roughness of 0.
These guide rolls 11 and 13 are metal rolls of 5 seconds or less, and are relatively hard and have approximately the same hardness as the ferromagnetic metal thin film layer formed on the substrate 6''2. Even if it comes into contact with the magnetic metal thin film layer, the surface will not be scraped by the ferromagnetic metal thin film layer, and the ferromagnetic metal thin film layer will not be scratched by the scrapings. Therefore, the guide rolls 8.1 whose outer circumferential surfaces of these metal rolls 18 are coated with a coating 19 made of a polymeric organic compound are used.
0, tension roll 9.12 and surface roughness 0.5
The substrate 6 that is run and guided by the metal guide rolls 11 and 13 having a size of 11 and 13 is hardly scratched on its front and back surfaces and the ferromagnetic metal thin film layer formed on the substrate, and the occurrence of dropouts is well suppressed. can do.

Guide roll 8.10 and tension roll 9.12
As shown in the figure, for the guide member in which the outer peripheral surface of the metal roll 18 is coated with a coating 19 made of a polymeric organic compound, the polymeric organic compound to be coated may be polyethylene resin or Teflon, which is relatively soft and has a small coefficient of friction. ,Nylon,
Cotton, urethane rubber, etc. are preferably used, and these can be made by, for example, covering the outer peripheral surface of the metal roll 18 with a cylindrical molded product made of nylon resin, cotton or urethane rubber, or polyethylene resin. Alternatively, it can be coated by coating the surface of a metal roll with a film made of Teflon and baking it. The thickness of the coating 19 made of a high-molecular organic compound coated in this way is 1 to 10 mm in the case of a coating made of nylon, urethane rubber, and cotton in order to have an appropriately small coefficient of friction and appropriate softness. 10 for polyethylene resin and Teflon.
It is preferable to set it within the range of ~500μ. Also, the coating 19
If the surface roughness of
It is preferable that the eL high value is 3 μ) or less. Further, the metal rolls such as the guide rolls 11 and 13 that are in contact with the ferromagnetic metal thin film layer formed on the substrate 6 preferably have a surface roughness of 0.5s or less, and a surface roughness greater than this. If it is too much, the surface of the ferromagnetic metal thin film layer in contact with these guide rolls 11 and 13 may be scraped, which is not preferable.

Note that the guide members shown in the drawings are merely examples, and the guide members are not limited to those shown, and may be increased or decreased as necessary. In addition to motor drive, these guide members may be driven by any method such as a timing belt method synchronized with the guide member, or a method in which they are rotated by frictional resistance with the substrate through bearings, and the substrate feed rate It should be rotated at a speed that matches.

As the substrate for forming the ferromagnetic metal thin film layer, a plastic film made of commonly used polymer moldings such as polyester, polyimide, polyamide, etc. and a nonmagnetic metal plate such as copper are used. Formation is performed by means such as sputtering and ion blasting in addition to vacuum evaporation.

In addition, ferromagnetic materials include single metals such as cobalt, nickel, and iron, as well as alloys or oxides of these metals, and C.
Commonly used ferromagnetic materials such as o-P and Co-Ni-P are widely used.

Next, embodiments of the invention will be described.

Example 1 As shown in FIG. 2, a guide roll 8.10, a tension roll 9.12, a metal roll 18 having a coating 19 made of polyethylene resin with a thickness of 400 μm and a surface roughness of IS formed on the outer peripheral surface. and a chrome-plated metal guide roll 1 with a thickness of 50μ and a surface roughness of 0.3s.
1.13, a polyester film 6 with a thickness of 11 μm is deposited on the raw roll 7 using a vacuum evaporation device arranged between the cylindrical can 5, the raw roll 7, and the take-up roll 14 as shown in FIG. The winding roll 1 is moved along the circumferential surface of the cylindrical can 5 via the guide roll 8, tension roll 9, and guide roll 10, and is moved along the circumferential side of the cylindrical can 5 via the guide roll 11, tension roll 12, and guide roll 13.
4 to be wound up, and the ferromagnetic material evaporation source 15 is a cohartonisokel alloy (weight ratio 85:15) 1
．． I set 6. Next, the inside of the vacuum chamber 1 is evacuated to a pressure of 5×10 −51 by using the exhaust systems 3 and 4, and the cohalt-nisokel alloy 16 is heated and evaporated to coat the polyester film 6 with cobalt having a thickness of 0.1 μm. A ferromagnetic metal thin film layer made of a nickel alloy was formed. Afterwards, this was cut to a predetermined width to make magnetic tape.

Example 2 In Example 1, a metal guide roll 11.1 having a thickness of 50μ and having various surface roughnesses was plated with chrome.
A large number of magnetic tapes were made in the same manner as in Example 1, except that Example 3 was used in place of the metal guide roll used in Example 1.

Example 3 In Example 1, a guide roll 8.10 and a tension roll 9.12 were prepared in which the outer circumferential surface of the metal roll 18 was coated with a coating 19 made of tetrafluoroethylene with a thickness of 200μ and a surface roughness of 2S. A magnetic tape was produced in the same manner as in Example 1, except that the following was used in place of the guide member used in Example 1.

Example 4 In Example 1, the outer peripheral surface of the metal roll 18 was made of nylon and had a thickness of 6 mm and a surface roughness of 3s. i!
A magnetic tape was produced in the same manner as in Example 1, except that guide rolls 8.10 and tension rolls 9.12 coated with No. 19 were used in place of the guide members used in Example 1.

Example 5 In Example 1, a guide roll 8, 10 and a tension roll 9 were prepared in which the outer peripheral surface of the metal roll 18 was coated with a coating 19 made of cotton and having a thickness of 6 mm and a surface roughness of 3s.
．． A magnetic tape was made in the same manner as in Example 1 except that 12 was used in place of the guide member used in Example 1. Example 6 In Example 1, the outer peripheral surface of the metal roll 18 was made of urethane rubber. Example except that the guide roll 8.10 and tension roll 9.12 coated with a coating 19 having a thickness of 1'Omm and a surface roughness of 3s were used in place of the guide member used in Example 1. A magnetic tape was made in the same manner as in 1.

Comparative Example 1 In Example 1, the outer peripheral surface of the metal roll 18 has a thickness of 5
Except that metal guide rolls 8, 10, 11, 13 and tension rolls 9, 12, which were plated with 0μ chrome and had a surface roughness of 0.35, were used in place of the guide members used in Example 1. A magnetic tape was made in the same manner as in Example 1.

For the magnetic tapes obtained in Examples 1.3 to 6 and Comparative Example 1, a 4 MHz signal was recorded and reproduced, and the number of times the output dropped by 20 dB, 5 μsec or more from the standard reproduction output was counted as dropout per unit time, We looked at the number of dropouts.

The table below shows the results.

Table Also, for the magnetic tape obtained in Example 2, a 4 MHz signal was recorded and reproduced in the same manner as described above, and the number of times the output dropped by 20 dB and 5 μsec or more from the standard reproduction output was counted as a dropout per unit time. I checked the number of outs.

FIG. 3 is a graphical representation of the results.

〔Effect of the invention〕

As is clear from the above table, the magnetic tapes obtained in Examples 1.3 to 6 all had a smaller number of dropouts than the magnetic tape obtained in Comparative Example 1. It can be seen that according to the manufacturing method and apparatus, scratches that occur during the manufacturing of the magnetic recording medium are extremely well suppressed, and a magnetic recording medium with excellent electromagnetic conversion characteristics can be obtained. Also,
As is clear from Fig. 3, when the surface roughness of the metal guide roll becomes 0.5 s or less, the number of dropouts decreases to within an allowable range (100111i1/min or less), which indicates that The surface roughness of the metal guide member in contact with the formed ferromagnetic metal thin film layer is 0.5.
It can be seen that it is preferable to make it less than or equal to s.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a vacuum evaporation apparatus used to carry out the manufacturing method of the present invention, FIG. 2 is an enlarged cross-sectional view of a guide member used in the present invention, and FIG. FIG. 3 is a relationship diagram between the number of dropouts of the magnetic tape obtained in 1 and the surface roughness of the metal guide member used in manufacturing the magnetic tape. 1... Vacuum chamber, 5... Cylindrical can, 6... Substrate, 7... Original fabric roll, 8.10.11.13... Guide roll, 9.12... Tension roll , 14・
... Winding roll, 15 ... Ferromagnetic material evaporation source, 16
... Ferromagnetic material, 18 ... Metal roll, 19 ... Coating patent applicant Hitachi Maxell Ltd. Figure 1 Figure 2 Figure 1b Metallic roll

Claims (1)

[Claims] 1. A magnetic recording medium in which a ferromagnetic material is supplied from a ferromagnetic material supply source to a substrate that is continuously moved by a substrate moving support device in a vacuum chamber to form a ferromagnetic metal thin film layer. In the manufacturing method, a guide member whose outer peripheral surface is coated with a film made of a high-molecular organic compound is disposed between the substrate moving and supporting devices so as to be in contact with the substrate, and a metal guide with a surface roughness of 0.5 seconds or less is provided. The member is arranged so as to be in contact with a ferromagnetic metal thin film layer formed on the substrate, and the ferromagnetic material is evaporated onto the substrate that is guided while traveling in contact with a guide member whose outer peripheral surface is coated with a film made of a polymeric organic compound. A ferromagnetic metal thin film layer is formed by directing the gasified ferromagnetic material from a source, and after forming the ferromagnetic metal thin film layer, the ferromagnetic metal thin film layer is placed on a metal guide member with a surface roughness of 0.5s or less. A method for producing a magnetic recording medium characterized in that the magnetic recording medium is guided so as to be in contact with the magnetic recording medium.A magnetic recording medium is produced by disposing a substrate moving support device and a ferromagnetic material supply source facing the substrate moving support device in a vacuum chamber. In a recording medium manufacturing apparatus, a guide member whose outer peripheral surface is coated with a film made of a high-molecular organic compound is disposed at a position in contact with a substrate moving between substrate moving and supporting devices, and the guide member has a surface roughness of 0.
A magnetic recording medium manufacturing apparatus characterized in that a metal guide member of 5 seconds or less is disposed at a position in contact with a ferromagnetic metal thin film layer formed on a substrate moving between substrate moving and supporting devices.