JPS61250837A - Production of vapor deposited magnetic tape - Google Patents

Abstract

PURPOSE:To form parts where a magnetic material is not deposited by evaporation and which have light transmittivity and to obtain a magnetic tape having the light transmittable parts by disposing means for preventing the vapor deposition of the magnetic material at every prescribed interval in the stage of depositing the magnetic material by evaporation on a base film having light transmittance. CONSTITUTION:The base film 1 and a masking tape 6 are run at an equal speed by the rotation of a cooling can 2 and the magnetic material is evaporated from an evaporating source 3 toward the base film 1 on the can 2. The surface of the film 1 is exposed from a through-hole 6a of the tape 6 during the traveling of the film 1 on the can 2 simultaneously with the through-hole 6 and therefore the magnetic material is deposited thereon by evaporation and the magnetic tape part la is formed. The magnetic material is not deposited thereon by evaporation during the traveling of the film 1 simultaneously with the masking part 6b on the can 2 and the light-transmittable part 1b consisting of the film 1 alone where the magnetic material is not deposited by evaporation is formed by as much as the length of the masking part 6b.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a vapor deposited magnetic tape having a light-transmitting portion at its leading end and end.

[Summary of the invention]

The present invention provides a method for manufacturing a vapor-deposited magnetic tape having a light-transmitting portion at a leading end and a terminal end thereof, in which a magnetic material deposition prevention means is provided at predetermined intervals when a magnetic material is vapor-deposited on a light-transmitting base film. By arranging the tape, a light-transmitting part is formed without the magnetic material deposited, and a good vapor-deposited magnetic tape having a light-transmitting part at the tip and end can be easily obtained. .

[Conventional technology]

Conventionally, methods of manufacturing magnetic tapes by vapor deposition are known. FIG. 4 is a diagram showing the configuration of a vacuum evaporation apparatus αυ for manufacturing magnetic tape by this evaporation. This vacuum evaporation apparatus 0υ is a vacuum pump α
The inside is kept in vacuum by □□. - Inside the vacuum chamber az, a cooling can (2) is rotatably arranged, and a base film (11 is provided) and a shaft (5a ) and the winding shaft (5b).

A part of the loading surface of the cooling can (2) of this base film (1) faces the evaporation source (3), and the evaporation direction of the evaporation source (3) faces the cooling can (2). From this evaporation source (3), a magnetic material such as a Co-Ni alloy is evaporated and deposited toward the base film (IJ) on the cooling can (2). To limit the material deposition angle, a cooling can (
A part of the loading surface of the base film (1) of 2) is covered with a fixed mask (4). By doing this, the magnetic material deposition angle θ from the evaporation source (3) to the base film (1) becomes a constant narrow angle, and the base film (IJ) is transferred from the supply shaft (5a) side to the take-up shaft (5b ) side, a magnetic tape with a magnetic material deposited on the base film (1) is formed and wound around the winding shaft (5b). magnetic tape is
It has the advantage of being suitable for high-density recording.

On the other hand, when a magnetic tape is used in a video tape recorder or the like, it is necessary to detect the leading and trailing ends of the tape in some way. One method for detecting this tape end is to make the tape end part a transparent tape that has light-transmitting properties, and to place a light emitting part and a light receiving part in the middle of the tape running system with the tape sandwiched between them. . By doing this, in the magnetic tape part, the light from the light emitting part is blocked by the magnetic tape and no light enters the light receiving part, but when it comes to the transparent tape part of the terminal, the light from the light emitting part is transmitted to the light receiving part. The end of the tape can be detected by the incidence of light on the light receiving section. In order to use a transparent tape as the end of the tape for detection in this way, the fifth
As shown in the figure, a transparent tape b such as a sensing tape was connected to the end of the magnetic tape a by a splicing tape C.

[Problem that the invention seeks to solve]

However, if the splicing tape C is used for connection as in the example shown in FIG. 5, the thickness of the tape at this connection part will be thicker by the amount of the splicing tape C than other parts. If there is a step part with a different thickness as shown in Fig. 6, when the tape is wound onto the reel d, the step e will spread to the magnetic tape a overlapping the splicing tape C. If there is a step e on this magnetic tape a, the part of the step e will not fit well with the magnetic head.
There was a risk that accurate signal recording and playback would not be possible. Further, there was a problem in that the work of connecting the transparent tape B with the tin rising tape C was a very time-consuming work. Furthermore, if the connection is insufficient, there is a risk that the tape will break at the connection.

In view of the above-mentioned points, it is an object of the present invention to provide a method for manufacturing a vapor-deposited magnetic tape having a transparent portion that does not change the thickness of the tape and can be easily manufactured.

[Means for solving problems]

The method for producing a vapor-deposited magnetic tape of the present invention includes, for example, as shown in FIG. Then, magnetic material deposition prevention means (6b) are arranged between the evaporation source (3) and the base film (υ) at predetermined intervals so that there are portions where no magnetic material is deposited at predetermined intervals. This is what I did.

[Effect]

By manufacturing as described above, the part where the magnetic material is not vapor-deposited becomes a translucent part, and by using this translucent part as the end of the tape, it can be used to detect the end. Vapor-deposited magnetic tapes can be produced that have transparent portions.

[Example] ・Hereinafter, an example of the method for manufacturing the vapor-deposited magnetic tape of the present invention will be described.
Let's explain with reference to FIG. In FIG. 1, parts corresponding to those in FIG. 4 are designated by the same reference numerals, and detailed explanation thereof will be omitted.

Figure 1 shows the inside of the continuous vacuum evaporation equipment, and shows the cooling can (
A base film (1) made of a translucent material is loaded on the surface of the base film (2).
Load masking tape (6) from above 1).

This masking tape (6) is the base film (1)
Similarly, it is sent out from the supply shaft (7a) and sent out from the take-up shaft (7b).
). The first skinning tape (6) has a width wider than the width of the base film (1), and has continuous through holes (6a) in the longitudinal direction at predetermined intervals. The part not covered is the masking part (6
b). Note that the opening width of the through hole (6a) in the width direction of the masking tape (6) is slightly wider than the width of the base film (1).

By loading the masking tape (6) and base film (1) formed as described above into the cooling can (2), the rotation of the cooling can (2) causes the base film (1) and the masking tape (1) to ) run at a constant speed to evaporate the magnetic material from the evaporation source (3) towards the base film (1) on the cooling can (2). Here, the base film (1) is attached to the through hole (6) of the masking tape (6).
When running on the cooling can (2) at the same time as a), the surface of the base film (1) is exposed through the through hole (6a), so the magnetic material is deposited and the magnetic tape part (1)
a). However, when the base film (1) runs on the cooling can (2) at the same time as the masking part (6b) of the masking tape (6), the surface of the base film (IJ) is covered by the masking part (6b). Therefore, the magnetic material from the evaporation source (3) will not be deposited on the surface of the base film (1) and will not be deposited on the masking part (
The transparent portion (1b) consists only of the base film (1) on which no magnetic material is deposited for a length of 6b). The transparent parts (1b) are provided between the magnetic tape parts (1a) at each interval of the masking parts (6b), and the winding shaft (5b)
It is wound up.

When the magnetic tape manufactured by winding in this manner is obtained as a videotape, the transparent part (1b) is cut to form the leading edge and the trailing edge. It has a light part (1b),
The leading edge and trailing edge can be detected by light transmitted through the tape. By manufacturing in this way, the magnetic tape part (1a) and the transparent part (1b) can be continuously formed on the base film (1), and the work of connecting transparent tape using splicing tape or the like becomes unnecessary. At the same time, there is no risk of cutting between the magnetic tape section (1a) and the transparent section (1b). Further, the splicing tape does not produce parts of different thickness, and even when the tape is wound onto a reel, there is no stepped part as shown in FIG. 6, and there is no possibility that recording and reproduction cannot be performed accurately. In addition, the thickness of the magnetic layer of vapor-deposited magnetic tape is very thin, for example, the base film thickness is 10 μm.
On the other hand, since the magnetic layer thickness is about 0.1 μm, there is almost no change in the thickness of the magnetic tape portion (1a) and the light-transmitting portion (1b) depending on the presence or absence of the magnetic layer.

In the above embodiment, the masking tape (6) is passed from the supply shaft (7a) to the take-up shaft (7b), but it can also be made endless.

Next, another embodiment of the method for producing a vapor-deposited magnetic tape according to the present invention will be described with reference to FIG. In this Figure 2, the fourth
Portions corresponding to those in the figures are given the same reference numerals, and detailed explanation thereof will be omitted.

In the example shown in Fig. 2, in addition to the fixed mask (4) that limits the deposition angle θ between the evaporation source (3) and the cooling can (2), a movable mask (8) is provided to manufacture the evaporated magnetic tape. It is something to do. This movable mask (8) is located along the cooling can (2) outside the range of the deposition angle θ from the evaporation source (3) where the magnetic material is deposited on the base film (1). It can be moved along the outer periphery of the cooling can (2) to a position where it comes into contact with the fixed mask (4) (the position shown by the two-dot chain line). Then, when the movable mask (8) comes into contact with the fixed mask (4), the base film (13
The base film (
1] Prevents the deposition of magnetic material on the surface. By moving the movable mask (8) to a position that prevents this vapor deposition at predetermined intervals, portions where the magnetic material is not deposited, that is, transparent portions, are created at predetermined intervals.
A vapor-deposited magnetic tape similar to the example shown in FIG. 1 can be manufactured. It is easy to understand that the manufacturing method according to the example in FIG. 2 also provides the same effects and effects as the example in FIG. 1.

Further, FIG. 3 is a diagram showing still another embodiment of the method for manufacturing a vapor-deposited magnetic tape of the present invention. In this example in FIG. 3, a fixed cover (9) is provided around the evaporation source (3), and
A movable cover 00 is provided which is normally located outside the range of the evaporation angle θ of the evaporation source (3) and can be moved to a position covering the evaporation angle θ as necessary. This movable cover 〇〇 moves to completely cover the evaporation source (3) together with the fixed cover (9), thereby preventing the magnetic material from being deposited on the base film (1). By moving this power bar 00) above the evaporation source (3) at predetermined intervals during the production of the vapor deposition tape, a portion where no magnetic material is vapor deposited, that is, a portion having translucency, is created. 1st
A vapor-deposited magnetic tape similar to the illustrated example can be manufactured. The manufacturing method according to the example in FIG. 3 also has the same effect and function as the example in FIG.
It is easy to understand that the effect can be obtained.

Note that the present invention is not limited to the above-described embodiments, and it goes without saying that various other configurations may be adopted without departing from the gist of the present invention.

〔Effect of the invention〕

According to the method for manufacturing a vapor-deposited magnetic tape according to the present invention, it is possible to obtain a vapor-deposited magnetic tape having a light-transmitting part continuous with the magnetic tape part, and the light-transmitting part for detecting the end of the tape can be easily formed during manufacturing of the magnetic tape. In addition, since the light-transmitting part is continuous with the magnetic tape part, there is no need to connect the transparent tape, and there is no step difference, so recording and reproduction can be performed accurately.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a perspective view showing the main parts of a vapor deposition apparatus according to an embodiment of the method for manufacturing a vapor-deposited magnetic tape of the present invention, and FIG. 2 is a perspective view of a vapor deposition apparatus according to another embodiment of the present invention. FIG. 3 is a cross-sectional view showing an evaporation source of a vapor deposition apparatus according to another embodiment of the present invention, and FIG. 4 is a cross-sectional view showing a conventional vapor deposition apparatus.
FIGS. 5 and 6 are explanatory diagrams of conventional magnetic tapes. (1) is the base film, (1 is the magnetic tape part, (1 is the
b) is the transparent part, (2) is the cooling can, (3) is the evaporation source,
(6) is masking tape. C Planar view of the Tate Takenagadaiji (Fig. 5) Plan of operation of the vacuum steaming device (Fig. 5)

Claims (1)

[Claims] In a method for manufacturing a vapor-deposited magnetic tape in which a magnetic material is vapor-deposited from an evaporation source onto a light-transmitting base film, means for preventing vapor deposition of the magnetic material is provided between the evaporation source and the base film at predetermined intervals. 1. A method for producing a vapor-deposited magnetic tape, characterized in that the magnetic material is arranged so that the magnetic material is not vapor-deposited at predetermined intervals.