JPH0332131B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a magnetic recording medium having a flexible metal disk as a base and forming a magnetic thin film for magnetic recording on the base. More specifically, the present invention relates to a method of manufacturing a magnetic recording medium in which the magnetic recording medium is continuously formed into a flexible disk shape by a photoetching method.

At present, flexible disk type magnetic recording and reproducing devices are being incorporated into a large number of systems, taking advantage of their small size and light weight.

A magnetic recording medium in which a magnetic thin film for magnetic recording is formed on a flexible metal disk base has the following features: (1) There is no humidity expansion.

(2) The drive spindle hole is strengthened and the center position is accurately determined, which not only improves recording density but also improves reliability and durability, which is advantageous.

FIG. 1 shows a flexible disk manufactured according to the present invention.

1 is a flexible disk, 2 is a flexible non-magnetic metal plate substrate with a thickness of about 100 microns or less, 3 is a magnetic thin film for magnetic recording, 4 is a lubricating layer, 5 is a drive spindle hole, and 6 is a jacket.

Conventional flexible disks are manufactured by coating the surface of a synthetic resin base such as polyester film with a magnetic material and then cutting it into a flexible disk shape using a press, or by coating the surface of a synthetic resin base that has been cut out with a press with a magnetic material. has been manufactured in. However, when the above-mentioned manufacturing method is applied to a flexible disk formed from a flexible metal plate substrate, burrs and distortion occur, so that (1) the contact between the magnetic head and the magnetic recording medium cannot be maintained constant;

(2) Burrs become entangled in the nonwoven fabric on the back of the jacket, increasing rotational torque and causing uneven rotation.

Problems such as this may occur.

The manufacturing method according to the present invention eliminates such drawbacks, and is a method for continuously manufacturing flexible disks using a photoetching method. According to this manufacturing method, high-quality flexible disks without distortion and burrs can be obtained. This not only improves productivity but also improves productivity.

Hereinafter, the present invention will be explained in detail based on one example.

In FIG. 2, a magnetic recording medium sheet 7 whose surface is coated with a magnetic material 3 by sputtering, coating, etc. on a flexible metal plate substrate 2 is wound into a roll.

In FIG. 3, a photosensitive resin 8 is coated on the front and back surfaces of a magnetic recording medium sheet 7 in which a magnetic material is formed on both sides of a sheet-like flexible metal plate substrate.

Similar masks are placed on both sides of this magnetic recording medium sheet and exposed to ultraviolet light to effect the photosensitive resin in the portions corresponding to the desired pattern shape.

Thereafter, the unexposed portions are removed and developed to highlight the disk shape and the shape of the connecting portion 9 as a bridge, which is designed to prevent each disk from falling apart in a subsequent process.

After this development, the exposed magnetic material and the metal portion of the flexible metal plate substrate are etched to obtain a magnetic recording medium precursor in which the disk shapes are connected at the connecting portion 9.

Finally, each disk is separated from the connecting portion 9 to obtain a high quality flexible disk free of burrs and distortion.

As described above, according to the manufacturing method of the present invention, a magnetic recording medium having a flexible metal disk as a substrate and a magnetic thin film for magnetic recording formed on the substrate can be obtained without burrs or distortion. In addition to this, productivity can also be improved by continuous etching.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a flexible disk manufactured according to the present invention. FIG. 2 shows a magnetic recording medium wound into a roll. FIG. 3 shows a magnetic recording medium patterned with a flexible shape. DESCRIPTION OF SYMBOLS 1... Flexible disk, 2... Nonmagnetic metal base, 3... Magnetic thin film for magnetic recording, 4... Lubricating layer, 5... Drive spindle hole, 6... Jacket, 7... Magnetic recording medium sheet, 8 ...Photosensitive resin, 9... Part that connects each disk (connection part).

Claims (1)

[Claims] 1. A step of forming a magnetic material on both sides of a sheet-like flexible metal plate substrate, and forming a photosensitive resin on both sides of the flexible metal plate substrate on which the magnetic material is formed. A step of placing similar masks on both sides of the flexible metal plate substrate on which the photosensitive resin is formed and exposing a plurality of disk shapes connected to each other at connecting portions, developing and etching the flexible metal plate substrate on which the photosensitive resin has been exposed; obtaining a plurality of disk-shaped magnetic recording medium precursors that are connected to each other at connecting portions; and the magnetic recording medium precursors. A method for producing a magnetic recording medium, the method comprising: obtaining a magnetic recording medium by separating the connection portions of the magnetic recording medium.