JPS62183044A - 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 laminating a thin magnetic layer on a base plate to form a substrate. CONSTITUTION:A thin magnetic layer 2 is laminated on a base plate 1 by sticking with an adhesive or the like to form a substrate 7, and a recording layer 3 is formed on the layer 2. The layer 2 may be made of a high permeability material or a permanent magnet material. A glass sheet, a plastic sheet or film may be used as the base plate 1. The layer 3 may be formed on the other side of the plate 1. At this time, the layer 3 may be composed of a layer 4 of a low m.p. substance and a metallic reflecting film 5. By the structure, positioning to the prescribed position of a recording and reproducing device before the recording or reproduction of information is 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, and cards that are more portable than these recording media and have the same size and larger capacity than the currently popular magnetic carts. Proposals are also beginning to be made for recording media of the same size.

In conventional recording media, plastic plates or films are widely used as substrates, but these substrates are thin and prone to warping of the substrate 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 laser beam autofocus.

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 in particular, card-shaped media are characterized by their portability, so they are even more likely to suffer from deterioration in reliability due to deformation of the substrate.

[Problems to be solved by the invention] The present invention has been made in view of such conventional technology, and is a method for recording and reproducing information using an optical recording medium having a substrate made of laminated magnetic thin layers. In other words, when the optical recording medium is housed in the magnetic storage section of the information recording/reproducing device, the magnetic attraction between the two allows easy and accurate positioning during information recording and reproduction. The present invention was completed by discovering what can be done and what can be done.

[Means for Solving the Problems] The present invention is an optical recording medium characterized by having a substrate formed by laminating magnetic thin layers.

The present invention will be explained in detail below.

1 to 3 are sectional views each showing an example of the optical recording medium of the present invention. In FIG. 1, the optical recording medium of the present invention has a substrate 7 formed by laminating a magnetic thin layer 2 on a base plate 1, which is fixed with an adhesive or the like as required. A recording layer 3 is provided thereon.

FIG. 2 shows another example of the optical recording medium of the present invention, in which a recording layer 3 is formed on the other surface of the base plate 1 of a substrate 7 formed by laminating a magnetic thin layer 2 on the base plate 1. It is made up of the following.

FIG. 3 shows still another example, in which a magnetic thin layer 2 is laminated on a base plate 1 via an adhesive layer 6 to form a substrate 7, and a base plate l of the base plate 7 is formed. Low melting point material layer 4 on top and total 7%
This is an optical recording medium provided with a recording layer 3 formed by sequentially laminating reflective films 5.

In the present invention, the magnetic material used for the magnetic thin layer includes high magnetic permeability materials, permanent magnet materials, etc. Specific examples thereof include powdered carbonyl iron, silicon steel, silicon cast iron, phosphorus silicon iron, aluminum iron, Permalloy, molybdenmalloy, supermalloy, copper permalloy, iron cobalt, iron-nickel-silica-manganese, ferrite, carbon steel, tungsten steel, chromium steel, molybdenum steel,
cobalt steel, aluminum steel, platinum cobalt, platinum ore,
Examples include manganese, aluminum, silver, and bismuth manganese.

In the present invention, a magnetic thin layer can be obtained by pressurizing and stretching the above-mentioned magnetic material at an appropriate temperature and processing it to an appropriate thickness.

The thickness of the magnetic thin layer is 0.1 to 100 μm, preferably 1 to 100 μm.
If it is less than 0.1 mm, it is difficult to form a homogeneous film, and if it exceeds 100 mm, the weight of the cart itself increases and portability becomes worse.

Furthermore, the plywood in the present invention may be any material that is used as a substrate for ordinary recording media, such as glass plates, polycarbonate, plastic plates such as acrylic, and plastic films. .

The thickness of the plywood is 0.1 to 1.0 mm, preferably 0.
．． 1 gm ~0.5+aa+ or preferably 0.1pm
It is difficult to put it into practical use because the strength is weak and it is difficult to put it into practical use.
．． If it exceeds 0■, the weight and thickness of the card will increase and portability will deteriorate.

The above-mentioned magnetic thin layer is adhered and laminated to these plywood boards using an adhesive or the like as required to form a substrate.

The recording layer can be provided on the side adjacent to the magnetic thin layer or directly on the plywood such as a glass or plastic layer.

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 an organic polymer material.

Examples include a layer in which a thin metal layer 11 is laminated on a layer of a low melting point substance.

A reflective layer may be provided on the recording layer, if necessary, and the outer surface may be further coated 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 evenly planar state.

In particular, it is preferable that the substrate of the optical recording medium be thin and have a large planar shape because the magnetic attraction force will work evenly to form a good planar state.

[Function] Since the optical recording medium of the present invention has a substrate made of laminated magnetic thin layers, magnetism in the recording and 11f recording equipment is applied! It is presumed that when it is housed in a storage section that is placed in a vertical position, it is fixed in a predetermined position by the magnetic attraction force, allowing for accurate positioning and the like.

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

Example 1 Mumetal (composition Cu:Cr:N1=5:2 near 7 weight ratio) was heated and rolled to a uniform thickness of 0.3 mrn. 5.4cm vertically, horizontally 8.
A vinyl chloride transparent substrate of 57 cm and a thickness of 0.5111 m was laminated with an adhesive made of a vinyl chloride/vinyl acetate copolymer applied therebetween, and laminated by hot pressing and heating.

Furthermore, a recording layer was provided on the side opposite to the side on which the magnetic thin layer was provided. Kaya tonBl is used as a sublimable dye in the recording layer.
ue 156 (manufactured by Nippon Kapaku), dinitrotoluene (manufactured by Tokyo Kasei) as a low melting point auxiliary agent, and ethyl cellulose (manufactured by Kanto Chemical System) as a binder in a weight ratio of 0.1:1:
1, and a 20% toluene solution was coated onto the substrate using a bar coater to a film thickness of 5 pm. Furthermore, a reflective film of Au was deposited thereon to a thickness of 50 Å.

The optical recording card thus obtained had magnetic properties and good strength.

Next, information was recorded in the storage section of the cart using a magnetic recording and reproducing device.

Recording is performed using a semiconductor laser, with a wavelength of 8:1 Onm.
The recording power was 7 mW on the recording surface, and the irradiation beam diameter was 7 l.

When reproduced using a rotary laser with a power of 0.7+nW and an irradiation beam diameter of 5 gm, the S-ratio value was 48 dll.
Met.

Further, no change in the S/N value was observed even after repeated reproduction several dozen times.

Comparative Example 1 Vertical 5.4cm, Width 8.57cm, Thickness 0.5II
An optical recording layer was provided on a 1 m long substrate made only of polyvinyl chloride film without a magnetic thin layer under the same conditions as in Example 1, and when recording and reproduction were performed, the S/N value was 38 dB.
There was.

Further, when the reproduction was repeated several dozen times, the S/N value varied greatly.

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

(1) 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 adding magnetism to predetermined positions within the recording/playback device, flatness is ensured, making AF easier, reducing errors during recording/playback, and obtaining highly reliable information. It will be done.

(3) It becomes possible to attach it to other magnetic materials,
Easy to store and carry.

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

[Brief explanation of drawings]

1 to 3 are cross-sectional views showing embodiments of the optical recording medium of the present invention. ■...Bed plate 2...Magnetic thin layer 3...Recording layer 4...Low melting point material layer 5...Metal reflective film 6 ...Adhesive layer Figure 1 Figure 2

Claims (1)

[Claims] An optical recording medium characterized by having a substrate formed by stacking magnetic thin layers.