JPS5924446A - Production of magnetic recording medium - Google Patents

Abstract

PURPOSE:To enable the vapor deposition treatment for a magnetic recording medium of a thin metallic film type adequate for short wavelength recording sufficiently on a mass production scale without generation of any defects, by disposing a roll for stripping a tape between a rotary support and a winding shaft and driving the same by torque. CONSTITUTION:The tension to be applied on a substrate 1 by a roll 5 is large enough to strip the substrate 1 from a rotarty support 2, but a winding shaft 4 acts merely to take off the substrate 1 fed thereto and is therefore required to be given extremely small tension. A polyethylene terephthalate film of 9,000cm length (8.5mum thickness, 50cm width) is prepared in an example and a magnetic layer consisting of Co 80 Ni 20 having 0.1mum thicknes is formed at 45 deg. min. incident angle in oxygen kept under 2X10<-5>Torr by electron beam vapor deposition. The tension applied on the substrate from a stripping roll in order to pull the substrate apart from the rotary support is 5kg and the winding tension 2.5kg. No problems arise in the winding condition in such a stage.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a ferromagnetic layer made of a thin metal film on a polymer molded substrate, and is particularly suitable for using a wide and long substrate. The present invention provides a method.

Winding deposition is known in the decorative field and capacitor field, but it has only recently been applied to the production of magnetic tape, and its processing scale is still limited to decoration.

This is less than the loss of capacitors, etc.

In the conventional field, most of the evaporation materials were A, and the evaporation source was either an induction heating source or a resistance heating source, so it took a long time to separate the evaporated substrate from the rotating support. No tension was required. Therefore, even if the winding diameter was 60CrfL or 1oOC1rL, no curling occurred when the board was separated from the rotating support due to the tension from the take-up reel, and even if there was a curling, the product Performance was not affected.

However, when electron beam heating, which is suitable for manufacturing magnetic tape, is used as an evaporation source, due to the effects of secondary electrons, 2 reflected electrons, etc.
Electrostatic attraction is involved, requiring large tension forces to separate the deposited substrate from the rotating support.

The conventional method of obtaining this tension from a rotational torque applied to the winding shaft has the following disadvantages.

One of them is that the tension at the time of winding is excessive, so the average surface roughness of the substrate for vapor-deposited magnetic tape is 10.
If the plate is smooth and has a thickness of 0 Å or less, and the film does not slide smoothly, the edge of the wound tape rises up, creating a so-called ridged appearance, and the resulting wrinkles cause defects. That's true. Furthermore, if the length is extremely long, blocking may occur inside the rolled-up state. All of these are factors that determine the upper limit of the processing scale and become bottlenecks in mass production.

The purpose of the present invention is to solve the above-mentioned drawbacks in the prior art.A tape peeling roller is disposed between a rotary support and a winding shaft, and is driven by torque, so that
After the substrate is separated from the rotating support by the electrostatic force, it is wound onto the winding shaft with a tension smaller than that tension.

The present invention will be described in detail below using the drawings.

FIG. 1 shows an example of the main part configuration of a winding vapor deposition apparatus used to carry out the present invention. In this figure, other well-known elements, including the vacuum container, which are essential for carrying out the roll-up deposition but are not directly related to the present invention, are simplified and omitted.

As shown in the figure, the polymer molded substrate 1 is configured to move to a rotating support. 6 is a roller driven by 5 constant torque. Material 1 surface roughening etc. are selected as appropriate. 6 is a nip roller, which pinches the substrate 1 between the roller 6 and applies tension. 7 schematically shows an electron beam evaporation source, and 8 is a mask for regulating incidence.

The tension applied to the substrate 1 by the roller blades is sufficient to pull the substrate 1 away from the rotating support 2;
Since the winding shaft 4 only winds up the substrate 1 that is sent, it is only necessary to give it an extremely small tension J. Therefore, it is possible to set the board 1 to be wound up sufficiently loosely so that there is no possibility of defects occurring.

Next, more specific examples will be shown below.

- Prepare a polyethylene terephthalate film (thickness 8.5 μm, 2 width so cm) with a thickness of 19,000 mm, and expose a magnetic layer made of C08ONi20 with a thickness of 0.1 μm at a minimum incident angle of 46° in oxygen at 2×10 Torr with an electron beam. It was formed by vapor deposition.

The tension applied by the peeling roller to separate this substrate from the rotating support was 5.5 mm, and the winding tension was 2.5 mm.
It was Kff. There was no problem with the winding condition at this time.

On the other hand, when the substrate is separated by tension from the winding shaft without the present invention, there is a loss in the roller system (only for guiding) in the middle of the process, so when the substrate is separated from the rotating support, In order to maintain the tension of sK9, a tension of 7 Ky was required near the winding shaft. Therefore 3700m
When I wound up the length of , the ears started to stand out.

Note that the means for peeling the substrate from the rotating support is not limited to the combination of the roller 6 and nip roller 6 as described above, but also other mechanical means or combinations with air flow, etc., depending on the situation. Can be used.

As described above, according to the present invention, it is possible to sufficiently increase the scale of the vapor deposition process of a metal thin film type magnetic recording medium suitable for short wavelength recording to a mass production scale without occurrence of defects.

[Brief explanation of drawings]

The figure is a diagram showing an example of the main part configuration of a winding vapor deposition apparatus used to carry out the present invention. 1... Substrate, 2... Rotating support body, 4...
... Winding shaft, 5 ... Torque drive roller, 6... Nip roller, 7 ... Electron beam evaporation source.

Claims (1)

[Claims] A magnetic layer is formed by electron beam evaporation on a polymer molded substrate that moves along a rotating support, and a peeling means provided between the rotating support and the winding shaft is used to remove the magnetic layer after the magnetic layer is formed. A method for manufacturing a magnetic recording medium, comprising the step of separating the substrate from the rotating support and then winding the substrate onto the winding shaft with a tension smaller than the tension applied by the peeling means.