JP3295119B2 - Magneto-optical recording medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a magneto-optical recording medium, and more particularly, to a magneto-optical recording medium used for optical recording.

[0002]

2. Description of the Related Art In a conventional magneto-optical recording medium, a recording layer is provided on a polycarbonate substrate (light-transmitting substrate) by sputtering or vapor deposition, and an ultraviolet curable resin film (protective layer) is formed thereon by spin coating for protection. ) Is formed. Also, characters such as A to Z are put on a substrate or the like, and thereafter marked with magic or the like, and US Pat. No. 4,066,
As in the case of Japanese Patent No. 268, there is one that draws a pattern in a place other than the groove. However, at present, no barcode is formed on a recording film or the like.

Conventionally, when numbering media, manual writing takes too much time, and when numbering is performed by ink-jet or the like, there is a drawback that daily adjustment is required and the cost is high. In the case of (1), there is a problem that the mechanical properties are deteriorated due to the thickness of the ink, and the drive may not be applied.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a low reliability and a high reliability in a magneto-optical recording medium having good mechanical properties by forming a bar code by a recording film or a reflection film by sputtering. The purpose of this is to provide.

[0005]

To achieve the above object, the present invention provides (1)
The on the substrate and the interference layer and the magneto-optical recording layer and the dielectric layer and the reflective layer and an ultraviolet cured layer provided with the recording layer and the hard coat layer for antistatic on the opposite side provided further across the substrate, the recording
In magneto-optical recording medium having a control track on the end of the data area of the layer, to the formation of the bar code on the recording layer of the inner peripheral side of the control track,
Or (2) an interference layer, a magneto-optical recording layer, and a dielectric
Layer, a reflective layer, and an ultraviolet curable layer, and further sandwich the substrate.
A hard coat layer for antistatic on the side opposite to the recording layer.
At the end of the data area of the recording layer.
In the magneto-optical recording medium provided with a rack, the control
The interference layer and the recording layer
And a bar code is formed on the dielectric layer and the reflective layer, and (3) the bar code is formed in (1) or (2).
There are, the bar code, in which one of the same contents is characterized that it has been intermittently plurality formed in the media circumferential direction. Hereinafter, a description will be given based on examples of the present invention.

FIG. 1 is a block diagram for explaining an embodiment of a magneto-optical recording medium according to the present invention. In FIG. 1, 1 is a disk substrate, 2 is a control track, 3 is a bar code,
Is a data area, 5 is an interference layer, 6 is a magneto-optical recording layer, 7 is a dielectric layer, 8 is a reflective layer, 9 is an ultraviolet (UV) cured layer, 10
Denotes a hard coat layer, and 11 denotes a substrate. As the substrate 11, a plastic such as a glass acrylic resin or a polycarbonate resin is used. The thickness of the substrate is generally about 1.2 mm. As the magneto-optical recording layer 6, TbDyF
An amorphous magnetic alloy of a rare earth and a transition metal such as eCo and TbFeCo and a laminated film of Pt / Co are used. The film thickness is 15
It is about 0 to 900 °, preferably about 200 to 500 °.

The interference layer 5 uses a light interference effect of a transparent film having a high refractive index (1.9 to 2.3) to reduce noise by lowering the reflectance and to improve the C / N ratio. It is. The interference layer, SiNx, include SiZrNx and T ₂ O ₅ or the like. These films are dense, prevent moisture and oxygen from entering from the outside, have high corrosion resistance, have low reactivity with the magneto-optical recording layer, and are highly reliable materials. Although the optimum thickness varies depending on the refractive index, it is about 800 to 1200 °.

The dielectric layer 7 uses a transparent film having a refractive index of about 1.6 to 2.1 and is used to enhance the light interference effect. The same material as the interference layer is used as the material. The reflection layer 8 is made of Al (aluminum), Ag, or the like having high reflectance. The film thickness is suitably from 400 to 600 °. The ultraviolet-curable layer 9 is spin-coated with a spinner and cured with ultraviolet light to a thickness of about 4 to 5 μm. On the opposite side of the magneto-optical recording layer 6 with the substrate 11 interposed therebetween, a hard coat layer 10 is provided using a material of an ultraviolet curable resin having an antistatic effect of 10 ⁻¹⁰ Ω / □ or less. The hard coat layer is also spin-coated with a spinner to a thickness of about 4 to 5 μm. Except for the ultraviolet curable resin, it is formed by sputtering or vapor deposition.

When forming a magneto-optical recording layer or when forming all inorganic films (interference layer, recording film, dielectric layer and reflection layer) , a plurality of bar codes 3 are formed on the inner peripheral side of the control track 2 by a metal mask. (Optimally four or more). In this way, media numbering can be created without a dedicated numbering device, or can be created without handwriting (at low cost), and there is no mechanical property deterioration due to numbering ink, and reliability is improved. By using a transparent material such as plastic for the shutter of the cassette and the storage case of the cassette, the bar code 3 does not open the shutter, and the number and contents of the media can be known from the outside of the cassette storage case with a bar code reader.

Hereinafter, a specific embodiment will be described. When a polycarbonate substrate having a diameter of 130 mm is set, an inner peripheral mask (FIG. 2-12) and an outer peripheral mask (FIG. 2-13) provided with a bar code metal mask are set.
After being put in the sputtering apparatus, first, the gas was evacuated to 7 × 10 ⁻⁷ Torr, an interference layer SiNx was formed at 1100 °, and then (Tb ₀₅
A recording layer is formed on a Dy ₀₅ ) ₂₄ Fe ₆₈ Co ₈ target by magnetron sputtering at 200 ° C.
Then, a reflective layer Al was formed at 500 °, discharged from the sputtering apparatus, and an ultraviolet curable layer and an antistatic hard coat layer were formed to a thickness of 5 μm with a spinner within one hour.
After forming the media, the barcode of the media was read with a barcode reader, and the media number was confirmed.

[0011]

As apparent from the above description, the present invention has the following effects. (1) SL at the time of forming during or membrane formation of all the inorganic recording layer, since the metal mask on the inner circumferential side of the control track is formed with a bar code, the media numbering can be formed at low cost, of ink of numbering Since there is no mechanical property deterioration, reliability is also improved. (2) is intermittently plurality (four or more optimally) of the same contents barcode within the media circumferential direction because it is formed, which is easily barcode easily read.

[Brief description of the drawings]

FIG. 1 is a configuration diagram for explaining an embodiment of a magneto-optical recording medium according to the present invention.

FIG. 2 is a diagram showing an inner peripheral mask and an outer peripheral mask.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Disc substrate, 2 ... Control track, 3 ... Bar code, 4 ... Data area, 5 ... Interference layer, 6 ... Magneto-optical recording layer, 7 ... Dielectric layer, 8 ... Reflection layer, 9 ... Ultraviolet (UV)
Cured layer, 10: hard coat layer, 11: substrate.

Claims (3)

(57) [Claims] 1. An interference layer, a magneto-optical recording layer, a dielectric layer, a reflection layer, and an ultraviolet curing layer are provided on a substrate, and an antistatic hard coat layer is provided on the opposite side of the recording layer with respect to the substrate. provided, the magneto-optical recording medium having a control track on the end of the data area of the recording layer, a magneto-optical recording medium, characterized in that the formation of the bar code on the recording layer of the inner peripheral side of the control track . 2. An interference layer, a magneto-optical recording layer and a dielectric on a substrate.
Layer, a reflective layer, and an ultraviolet curable layer, and further sandwich the substrate.
A hard coat layer for antistatic on the side opposite to the recording layer.
At the end of the data area of the recording layer.
In the magneto-optical recording medium provided with a rack, the control
The interference layer and the recording layer
Magneto-optical recording medium wherein said <br/> to the formation of the bar code on the dielectric layer and the reflective layer. Wherein the bar code is, the magneto-optical recording medium according to claim 1 or 2, wherein ones of the same content to the media circumferential direction, characterized in that it is intermittently plurality formation.