JPH0823932B2 - Read-only magnetic media - Google Patents

Description

TECHNICAL FIELD The present invention relates to a read-only magnetic medium required for distributing a program such as a personal computer.

[Conventional technology]

Conventionally, in order to distribute a program for a personal computer or the like, it was first necessary to record a program to be distributed on a flexible magnetic disk (FD) called a diskette or floppy by using a flexible disk drive (FDD). .

The FD is configured as shown in FIGS. 4 (a) and 4 (b). That is, FIG. 4 (a) is a partially cutaway plan view, and FIG. 4 (b) is an enlarged cross-sectional view of a portion B of FIG. 4 (a). FD23 in which a resin layer 22 in which hard magnetic particles having a coercive force of 250 to 750 Oersted are uniformly dispersed and contained is provided on both surfaces of a thin plate-shaped substrate 21 made of polyethylene terephthalate, and a liner 24 made of a non-woven fabric is internally stuck. It is housed in a case 25 made of resin.

[Problems to be solved by the invention]

In FDD which rotates FD23 at 300 rpm, when recording a certain program in one FD23, it makes one rotation to search a predetermined recording area, one rotation to record in a ring called a track,
Therefore, it took 200 ms × 2 × 80 = 32000 ms, that is, 32 seconds to record over a ring called 80 tracks. In order to distribute the same program to 10,000 personal computers, it would take 89 hours just to record it on FD23, and moreover, strict control of FDD required for recording would be required, and therefore, it would be expensive. There was a problem that the distribution of the program was hindered.

An object of the present invention is to provide a read-only magnetic medium in which a program to be circulated is recorded and retained at a manufacturing stage, and the program has been recorded by FDD or the like for many hours. Is to make unnecessary.

[Means for solving problems]

A read-only magnetic medium according to the present invention has a layer made of resin A having a plurality of small holes or projections arranged on at least one surface according to the information to be recorded, and the small holes or projections are provided. The resulting recess is a sheet in which the resin B is filled, and the soft magnetic particles having a low coercive force are uniformly dispersed and contained in either the resin A or the resin B.

[Action]

In the present invention, since the soft magnetic particles having a low coercive force are contained in either one of the resin A and the resin B, the information on the small holes is detected as the magnetic information.

〔Example〕

1 (a) and 1 (b) show an embodiment of the present invention. FIG. 1 (a) is a partially cutaway perspective view of the seat, and FIG. 1 (b) is a view of FIG. 1 (a). It is a partially expanded sectional view.

In FIGS. 1 (a) and (b), 1 is a sheet, 2 is a layer made of a resin A provided with a plurality of small holes 3, and 4 is a soft magnetic particle 5 having a low coercive force uniformly dispersed and contained. The magnetic resins B and 6 filling the small holes 3 are protective layers.

FIG. 2 (a) is a partially cutaway view showing a state in which the seat 1 shown in FIG. 1 (a) is accommodated in a case 7, and FIG. 2 (b) is a portion A of FIG. 2 (a). FIG. 4 is an enlarged cross-sectional view of FIG. 1, in which a liner 8 made of non-woven fabric is attached inside a case 7 made of resin, and the sheet 1 is stored in the case 7.

FIG. 3 is a diagram for explaining the operation of the present invention, in which 11 is a magnetic head, which comprises a magnetoresistive effect element 12.
Reference numerals 13 and 13 'are magnetic yokes having a magnetic gap 14, and reference numeral 15 is a bias coil. When the sheet 1 is rotated in the same manner as the FD and a current is applied to the bias coil 15 of the magnetic head 11, when the resin B comes into the magnetic gap 14, the bias coil 15 causes the magnetoresistive effect element 12 to be generated. Since the passing magnetic flux increases, the presence or absence of the small hole 3 can be detected. That is, just like a compact disc used for digital recording / playback, it functions as a read-only medium in which information is recorded and retained at the manufacturing stage.

In order to provide the small holes 3 in the layer 2, a stamper may be manufactured by the same technology for manufacturing a compact disk and a resin may be injection-molded. The width and the depth of the small holes 3 are both about 2 μm and the thickness of the layer 2 is about 2 μm. A size of about 0.1 mm can be easily realized. Further, as soft magnetic particles having a low coercive force to be contained in the resin B filling the small holes 3 of this degree, FeO: 30%, Zn
_{O: 20%, Fe 2 O} 3: FeO · ZnO ferrite 50% of mole% of the composition can be applied. FeO / ZnO ferrite has a grain size of 0.
It has a coercive force of 50 oe and a saturation magnetic flux of about 7,000 G at 5 μm or less, and has excellent properties that cannot be obtained with ordinary MnZn ferrite. Therefore, a read-only medium having a recording density almost equal to that of the existing FD can be realized. Further, according to the present invention, as shown in FIG. 2A, it is possible to provide a read-only medium which can be handled in the same manner as an existing FD.

That is, it is possible to apply a DC current to the coil of the magnetic head of the FDD (the magnetic head of the FDD can be applied to the existing FDD, but in that case, there is a problem to be solved in terms of performance. The information on the read-only medium according to the present invention can be reproduced only by adding (remaining).

In addition, in the description using FIG.
However, it is obvious that the same is true even if the resin A has a projection and the depression is filled with the magnetic resin B. It is also clear that one of the resin A and the resin B may contain the soft magnetic particles having a low coercive force uniformly dispersed therein. Furthermore, the shape of the read-only medium according to the present invention is not limited to the disk shape, and may be a card shape.

〔The invention's effect〕

As described above, according to the present invention, at least one surface has a layer made of the resin A provided with a plurality of small holes or protrusions arranged according to the information to be recorded, and these small holes or protrusions are formed. Resin B in the recess due to the provision
In the copying of a program to be circulated in the past, since a soft magnetic particle having a low coercive force is uniformly dispersed and contained in either one of the resin A and the resin B as a read-only magnetic medium. It also eliminates the need for many hours of FDD recording and strict control of this recording. Furthermore, by simply adding a magnetic head composed of a magnetoresistive effect element to the existing FDD, there is an effect that information on a new read-only medium can be reproduced.

[Brief description of drawings]

1 (a) and 1 (b) are partially cutaway perspective views showing an embodiment of the present invention and a partially enlarged sectional view thereof, and FIG. 2 (a) is a seat shown in FIG. 1 (a). FIG. 2B is a plan view showing a state in which the
FIG. 3A is an enlarged cross-sectional view of the portion A, FIG. 3 is a view for explaining the operation of the present invention, and FIGS. 4A and 4B are conventional FDs.
FIG. 2 is a partially cutaway plan view for explaining the above, and an enlarged sectional view of a portion B thereof. In the figure, 1 is a sheet, 2 is a layer, 3 is a small hole, 4 is a magnetic resin B, 5 is soft magnetic particles, 6 is a protective layer, 7 is a case, and 8 is a liner.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masahiro Seki Inventor Masahiro Seki 3-9-11 Midoricho, Musashino-shi, Tokyo Inside Nippon Telegraph and Telephone Corporation Electronic Engineering Laboratory (56) Reference JP-A-59-33626 (JP, A) ) Actual development Sho 55-149839 (JP, U)

Claims (2)

[Claims] 1. A layer comprising a resin A having a plurality of small holes or protrusions arranged according to information to be recorded is provided on at least one surface, and the plurality of small holes or protrusions are provided. A read-only magnetic medium, which is a sheet in which dents are filled with resin B, and soft magnetic particles having a low coercive force are uniformly dispersed and contained in either the resin A or the resin B. 2. The read-only magnetic medium according to claim 1, wherein the soft magnetic particles having a low coercive force are made of FeO.ZnO ferrite.