JPS6114892A - Manufacture of magnetic record medium - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing a magnetic recording medium, and in particular, after forming a ferromagnetic thin film on a plastic substrate by vacuum evaporation, sputtering, ion blating, etc., The present invention relates to a method of manufacturing a magnetic recording medium that is cut into shapes.

Recently, in order to increase the saturation magnetic flux density and coercive force to achieve high output, Co, Co-Ni, and C have been used.

A magnetic recording medium in which a ferromagnetic metal such as -Cr is formed as a ferromagnetic thin film on a plastic film by vacuum evaporation sputtering or the like, typically a so-called "evaporation tape", has been put into practical use.

When manufacturing these tapes, a method is generally used in which a ferromagnetic thin film is formed on a wide plastic film and then cut into tapes of a predetermined width. However, conventional methods for manufacturing vapor-deposited tapes have had the disadvantage that cracks occur in the ferromagnetic thin film during cutting. This tendency is due to Co-Cr as a ferromagnetic thin film.
This is particularly noticeable when a thin film is formed.

An object of the present invention is to produce a magnetic recording medium having a ferromagnetic thin film on a plastic substrate such as a vapor-deposited tape by a method including a cutting process after forming a thin film sphere. It is an object of the present invention to provide a method for cutting a material into a predetermined shape without causing cracks in the material.

LLri JLJ! According to the research of the present inventor, the cause of cracks appearing in the ferromagnetic thin film during the cutting process of the plastic substrate on which the above-mentioned ferromagnetic thin film is formed is that the physical properties of the plastic film L and the ferromagnetic thin film are significantly different. , especially Co-Cr
The hardness of the thin film is extremely high, and as the cutting process continues for a long time, the shape of the tip of the blade changes and its sharpness deteriorates, resulting in stress on the ferromagnetic thin film and cracks. Served. In addition, such drawbacks can be solved by using a disc-shaped cutting blade,
It has also been discovered that this can be avoided by continuing the cutting operation while regenerating.

The method of manufacturing a magnetic recording medium of the present invention is based on such knowledge, and more specifically, the method of manufacturing a magnetic recording medium of the present invention involves forming a ferromagnetic thin film on a plastic substrate and then cutting the plastic substrate into a predetermined shape. In the manufacturing method, the plastic substrate is cut by a rotating disc-shaped blade, and while the cutting operation is performed, the disc-shaped blade is regenerated at a position different from the cutting position. This is a characteristic feature.

explain. The drawing is a side view in the traveling direction of a magnetic recording medium for explaining the cutting process of the present invention.

Referring to the drawings, it is made of polyester, polycarbonate, etc. and has a thickness of, for example, 8.0 to 12.0 pm and a width of 600 to 600 pm.
A substrate l made of a plastic film with a thickness of approximately 1000 mm is coated with a thickness of 100 mm by vacuum evaporation, sputtering, etc.
A wide magnetic recording medium (deposited tape) 3 is formed with a metal ferromagnetic thin film 2 of 0 to 5,000 layers. As the ferromagnetic metal magnetic material forming the metal ferromagnetic thin film 2, Co
, Co--Ni, Co--Cr, etc. are used, and although there are basically no limitations, a Co--Cr thin film, which has conventionally tended to have the problem of cracking, is most effective.

According to the present invention, while advancing the vapor deposition tape 3 to the right at a speed of about 30 m/min, a tool made of high-speed tool steel such as W-based or MO-based, for example, with a diameter of 80-100 mm is
, a disc-shaped blade 4 with a thickness of about 0.7 mm is, for example, 11
While rotating at a speed of about 00 rpm, the tape is cut into a tape having a predetermined width of about 8.0 mm. While the disk-shaped blade 4 continues cutting the vapor-deposited tape 3, a blade regeneration device 5 performs polishing and regeneration at a position other than the cutting position to keep the shape of the blade as constant as possible. At this time, the media feeding jig 6 is rotated at the same circumferential speed as the blade 4 to prevent wrinkles from forming on the media during the cutting operation, and the regenerating device 5 is made of diamond and stone pre-processed into the shape of the blade. During the cutting operation, the blade is polished and regenerated by contacting the rotating blade continuously or intermittently with a very weak force.

Through such a regeneration operation, the shape of the blade 4 is kept constant, so that the stress on the ferromagnetic thin film 2 is kept to a minimum. Therefore, it becomes possible to cut the vapor-deposited tape 3 without producing ranks as in the conventional case.

As explained above, according to the method for manufacturing a magnetic recording medium of the present invention, a magnetic recording medium having a ferromagnetic thin film on a plastic substrate such as a vapor-deposited tape can be cut after forming the thin film. When manufacturing a magnetic recording medium of a predetermined shape,
By regenerating the blade in parallel, the shape of the cutting blade can always be kept constant even during cutting. Therefore, it becomes possible to cut the ferromagnetic thin film without causing cracks due to unnecessary stress. Furthermore, the requirement to manufacture magnetic recording media of a constant width with high precision by cutting is also satisfied.

[Brief explanation of drawings]

The drawing is a side view in the traveling direction of a magnetic recording medium for explaining the cutting process of the present invention. 1...Plastic film substrate 2° @ 3...Wide magnetic recording medium 4 fist...Blade 5...7 Gravure device 6...Media feeding jig

Claims (1)

[Claims] A method for manufacturing a magnetic recording medium in which a ferromagnetic thin film is formed on a plastic substrate and then the plastic substrate is cut into a predetermined shape, the plastic substrate being cut by a rotating disc-shaped blade, and the cutting operation being performed. A method for manufacturing a magnetic recording medium, characterized in that reproduction of the disc-shaped blade is performed at a position different from the cutting position.