JPS62183045A - Optical recording medium - Google Patents

Abstract

PURPOSE:To attain simple and accurate positioning to the magnetized holding part of a recording and reproducing device by dispersing magnetic powder in a base material to form a substrate. CONSTITUTION:An optical recording medium is composed of a substrate 1 formed by dispersing magnetic powder in a base material, a recording layer 3 laminated on the substrate 1 with an adhesive layer 2 in-between and a reflecting layer 4. Fine powder of a high permeability material or a permanent magnet material may be used as the magnetic powder and an inorg. material or a polymer as the base material. By the structure, positioning to the prescribed position of a recording and reproducing device before the recording or reproduction of information can be made simple and accurate by magnetizing also the position of the device.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an optical recording medium on which information is recorded and reproduced by optical means, and in particular to a card-shaped optical recording medium on which information can be recorded and reproduced using a laser beam. Regarding recording media.

[Prior Art] In recent years, many recording media such as optical files and compact discs have been proposed. Many cart-shaped recording media have also begun to be proposed.

Do conventional recording media extensively use plastic plates or films as substrates?

These boards were thin and were prone to warping of the board itself and waving of the surface.

Such deformation of the substrate makes it difficult to position the substrate when it is attached to a device when recording or reproducing information, and also causes malfunction of the laser beam auto-7 orcus.

That is, such deformation of the substrate increases the malfunction rate during information recording and reproduction, causing a decrease in reliability. Specifically, deformation of the substrate has occurred even in conventional disk-type recording media, and since card-shaped media in particular are characterized by their portability, reliability is even more likely to deteriorate due to deformation of the substrate.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned conventional technology, and is directed to recording and reproducing information using an optical recording medium having a substrate made of an RJ material. In other words, when the optical recording medium is housed in the magnetized storage section of the information recording/reproducing device, the magnetic attraction between the two allows the information recording/reproducing surface to be easily and accurately aligned. The present invention was completed after discovering what was possible.

[Steps F to Solve the Problems (1) The present invention is an optical recording medium characterized by having a substrate containing magnetic powder.

The present invention will be explained in detail below.

FIG. 1 is a sectional view showing an example of the optical recording medium of the present invention. In FIG. 1, the optical recording medium of the present invention is constructed by laminating a recording layer 3 on a substrate 1 containing magnetic powder with an adhesive layer 2 interposed therebetween, and further providing a reflective layer 4 thereon. It is something.

In the present invention, a substrate is formed by dispersing magnetic powder obtained from a magnetic material that can be processed into fine particles among magnetic materials into a base material such as glass or a polymer substance.

As the magnetic material used to obtain the magnetic powder, highly permeable materials, permanent magnet materials, etc. are used, and specific examples thereof include powder carbonyl iron, silicon steel, silicon cast iron, phosphorus silicon iron, aluminum iron, and permalloy. , molybdenum permalloy, supermalloy, copper permalloy, iron cobalt,
Examples include iron-nickel-silica-manganese, ferrite, carbon steel, tank stainless steel, chromium steel, molybdenum steel, cobalt steel, aluminum steel, platinum kohal 1~, platinum iron, manganese aluminum silver, bismuth manganese, and the like.

The particle size of the magnetic powder is an average particle size of 0.1 mm or less, preferably l
If the tile exceeds [11 to 50 ALm or preferably 0,] mm, the thickness of the magnetic layer will increase, and as a result, the thickness of the entire card and! Since it will increase the amount of II,
Undesirable.

In the present invention, the base material to which the magnetic powder is added and dispersed to form the substrate may be any material that is used as a substrate for ordinary recording media.1 For example, inorganic materials such as glass, Examples include polymeric substances such as plastics such as polycarbonate, polymethyl methacrylate, polyethylene, and polystyrene.

In the present invention, a plate-shaped or film-shaped substrate is formed by blending the above-mentioned magnetic powder and a base material, mixing them uniformly, stretching them under pressure at an appropriate temperature, and processing them to an appropriate thickness. do.

The mixing ratio of the base material and magnetic powder constituting the substrate is 100% of the base material.
It is desirable that the magnetic powder be 10 to 100 parts by weight, preferably 30 to 80 parts by weight.If it is less than 10 parts by weight, the magnetic powder will be weak and may not be able to fully fulfill its intended function. If the amount exceeds that amount, it will be difficult to achieve uniform dispersion in the polymer.

The thickness of the substrate is 0.1 to 3. hm, preferably 0.1~
1.0 mm is desirable; if it is less than 0.11, the strength will be low and it will be difficult to put it into practical use; if it exceeds 3.01, the thickness and weight of the cart will increase, making it less portable.

Next, a recording layer is laminated on the top of the substrate through contact, if necessary.

The recording layer is not particularly limited, and any commonly used recording layer may be used, such as a layer in which metal particles are dispersed in a t-i polymer material, or a layer in which metal particles are dispersed in a low melting point material layer. Examples include a layer made of laminated thin films.

A reflective layer may be provided on the recording layer, if necessary, and the outer surface may be further covered with a protective layer.

In order to record and reproduce information using the optical recording medium of the present invention, when the optical recording medium is housed in a storage section formed by imparting magnetism to the information recording and reproducing device in advance, the magnetic attraction force As a result, the optical recording medium is attracted to the surface of the magnetic substrate in the storage section and is supported in an even planar shape.

In particular, it is preferable for the substrate of the optical recording medium to be thin and have a large surface area, since the magnetic attraction force acts evenly to form a good planar state.

[Operation] Since the optical recording medium of the present invention has a substrate made of a magnetic material, when it is placed in a magnetized storage section in a recording/reproducing device, it is fixed in a predetermined position by magnetic attraction and alignment etc. You can do it correctly.

[Example code] Next, the present invention will be explained in more detail with reference to Examples.

Example 1 Carbonyl iron particles with a particle size of approximately 10 g were dispersed in a polystyrene-acetone solution, and a 0.3 ml/11 thick substrate containing 50 parts by weight of magnetic powder per 100 parts by weight of the base material was molded by a casting method. did.

A recording layer consisting of a light-absorbing layer made of a mixture of nitrocellulose and carbon black was provided on the substrate to a thickness of 1.0 gm, and an aluminum vapor-deposited film of 100 A was further formed on the recording layer as a light-reflecting layer. Set the thickness.

Recording was performed using a semiconductor laser, the wave depth was 8:1 Onm, the power was 7 mW on the recording surface, and the irradiation beam diameter was 7 μm layer. When reproducing using the same laser with a power of 0.7 mW and an irradiation beam diameter of 5 Bm, the S/N ratio was 57 dB.
Met. Also, even after repeated playback several dozen times, the S/N
No changes were observed in the values.

Comparative Example 1 A recording layer similar to that of Example 1 was provided on a substrate made only of polystyrene film without a magnetic layer with a thickness of 0.30-1. Recording and reproduction were performed under the same conditions. 4
1 dB, and after repeating the playback several dozen times, the S/N will decrease.
The values varied widely.

[Effects of the Invention] As explained above, the optical recording medium of the present invention has the following excellent effects by having a substrate containing magnetic powder.

(13) By applying magnetism to predetermined positions within the recording and reproducing apparatus, positioning during recording and reproducing information becomes simple and accurate.

(2) In addition, by applying magnetism to predetermined positions within the recording and reproducing device, flatness is ensured and AF becomes easier.
Errors during recording and playback are reduced, and highly reliable information can be obtained.

(3) It becomes possible to attach it on other magnetic substances,
Storage and carrying become convenient.

For example, it can be stored by attaching it to a magnetic boat or a nearby magnetic material.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of the optical recording medium of the present invention.

Claims (1)

[Claims] An optical recording medium characterized by having a substrate containing magnetic powder.