JPH06333265A - Optical information recording medium - Google Patents

Abstract

PURPOSE:To enhance the adhesive strength of a protective layer to a metallic layer and to obtain an optical information recording medium having improved durability and shelf stability. CONSTITUTION:When a recording layer 3 made of a coloring material, a metallic layer 4 and a protective layer 5 are laminated on a substrate 1 to obtain an optical information recording medium, a continuously or discontinuously rugged part 7, 8 is disposed at an inner circumference part and/or an outer circumference part of the substrate 1 not covered with the metallic layer 4 at the outside of the recording region 2 and the protective layer 5 is formed on the rugged part 7, 8 as well as on the metallic layer 4. The rugged part 7, 8 may be a rugged part formed by the substrate 1 itself, the recording layer 3 formed on the substrate 1 or an underlayer. It is also preferable that the protective layer 5 is formed using a coating liq. contg. a substance which dissolves or swells the rugged part to some degree.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical information recording medium using a dye, and particularly to a CD-R excellent in durability and storage stability.
And optical information recording media.

[0002]

2. Description of the Related Art An optical information recording medium using a dye as a recording layer has a high sensitivity as compared with one using a recording material such as a metal, and an advantage that a recording layer can be easily formed by a spinner coating method. have. On the other hand, however, since the recording layer made of this dye generally has a low reflectance, it is often the case that a metal layer such as an Au layer is provided on the recording layer to improve the reflectance. In this case, it is general practice to further provide a protective layer on the metal layer in order to ensure durability and storage stability.

As described above, the recording layer made of a dye is generally formed by a spinner coating method. As shown in FIG. 8, when the recording layer 3 (2 is a recording area) is provided on the support 1 by the spinner coating method, the support 1 is provided due to the characteristics of the spinner.
Although the film formation start position on the inner peripheral side can be controlled to some extent, the film formation end position on the outer peripheral side cannot be controlled, and the recording layer 3 is formed on the entire surface except the inner peripheral side.

As shown in FIG. 9, the metal layer 4 is inside the outer peripheral edge of the support 1 in the outer peripheral portion, outside the recording area 2, and in the inner peripheral portion than the recording area 2. Although provided inside the center of the support 1, the metal layer 4 is usually formed in an area narrower than the recording layer 3 in the outer peripheral portion, and also in the inner peripheral portion in some cases. This is because the metal surface such as the Au layer is chemically inactive and most organic substances are hard to adhere to. Therefore, a part without a metal layer is provided on the inner and outer circumferences, and a lower layer (for example, a plastic support) other than the metal layer is provided. This is because it is usual to take measures to enhance the adhesion with the protective layer.

Further, as shown in FIG. 10, a protective layer 5 made of an ultraviolet curable resin or the like can be formed by a spinner coating method similarly to the recording layer 3, but its formation region covers the entire metal layer 4. Generally, it is formed in a range that is hard. Therefore, in the optical information recording medium having such a structure, the protective layer 5 is directly formed on the recording layer 3 on the outer peripheral portion of the support 1 and also on the inner peripheral portion in some cases. However, when a protective layer 5 made of an ultraviolet curable resin is laminated on the recording layer 3, when a dye is used for the recording layer 3, the dye has a weak cohesive force, so that the recording layer 3 is easily peeled and destroyed. .

Therefore, at the time of forming the protective layer, the recording layer 3 at the outer peripheral portion, and in some cases, the inner peripheral portion is dissolved and removed, and the protective layer 5 made of an ultraviolet curable resin or the like is brought into direct contact with the support 1 such as polycarbonate. Will be required. Therefore, when forming the protective layer, the excess recording layer 3 at the inner and outer peripheral portions is washed off with a solvent before forming the protective layer 5, or an ultraviolet curable resin of a type diluted with a monomer that dissolves the recording layer 3 is used. In general, the excess recording layer 3 is washed away at the same time when the protective layer is formed.

However, in the above-mentioned method, the adhesion between the protective layer 5 and the support 1 such as polycarbonate is a factor that controls the adhesiveness of all the contact surfaces of the protective layer 5 including the metal layer 3. It cannot be said that the protective layer 3 having sufficient adhesiveness is necessarily obtained only by removing the recording layers in the inner and outer peripheral portions.

[0008]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an optical information recording medium capable of improving the adhesion between the protective layer and the support and improving the durability and storage stability. is there.

[0009]

To achieve the above object, according to the present invention, in an optical information recording medium having at least a metal layer and a protective layer laminated on a support, the optical information recording medium outside the recording area of the support is provided. The inner peripheral portion and / or the outer peripheral portion has a portion where the metal layer is not provided, and the inner peripheral portion and / or the outer peripheral portion where the metal layer is not formed are provided with a concavo-convex portion continuously or discontinuously. In addition, an optical information recording medium is provided in which the protective layer is formed so as to cover the irregularities. Further, according to the present invention, in an optical information recording medium in which at least a metal layer and a protective layer are laminated on a support, there is a portion where the metal layer is not provided at least on the inner peripheral portion of the support outside the recording area. And an uneven portion is provided continuously or discontinuously on the inner peripheral portion where the metal layer is not formed and the outer peripheral edge surface of the support, and the protective layer is formed so as to cover the uneven portion. Provided is an optical information recording medium characterized by being formed. Further, according to the present invention, in the above-mentioned configuration, the protective layer contains a substance that dissolves or swells to some extent the uneven portion formed on the inner peripheral portion and / or the outer peripheral portion outside the recording area that finally adheres. There is provided an optical information recording medium characterized by being formed using a coating liquid. Further, according to the present invention, in the above constitution, the optical information recording medium comprises a plastic support / recording layer / metal layer / protective layer, a plastic support / subbing layer / recording layer / metal layer / protective layer,
Alternatively, there is provided an optical information recording medium comprising a plastic support / metal layer / protective layer. Further, according to the present invention, in the above constitution, the optical information recording medium is a recording layer / metal layer / protective layer comprising a plastic support / dye, or a recording layer / metal layer comprising a plastic support / undercoating layer / dye. / An optical information recording medium comprising a protective layer is provided.

The present invention will be described in more detail below. Figure 1
Is a diagram showing a configuration example of an optical information recording medium according to the present invention,
In the inner peripheral portion and / or outer peripheral portion of the support 1 outside the recording area 2,
Concavo-convex portions 7 and 8 are provided continuously or discontinuously on an inner peripheral portion and / or an outer peripheral portion having a portion where the metal layer 4 is not provided and the metallic layer 4 is not formed. A protective layer 5 is formed so as to cover the parts 7 and 8.

FIG. 5 shows a case where discontinuous uneven portions are formed on the inner peripheral portion and the outer peripheral portion of the support, and the uneven portions are indicated by 10 in the figure.
Indicated by. Further, FIG. 6 shows a case where continuous concavo-convex portions are formed on the inner peripheral portion and the outer peripheral portion of the support, and the concavo-convex portions are indicated by 11 in the figure. These discontinuous uneven portions 10
Alternatively, the continuous uneven portion 11 may be formed only on the inner peripheral portion or only on the outer peripheral portion.

Further, according to the present invention, as shown in FIGS. 2 and 3, the continuous or discontinuous uneven portion is only the inner peripheral portion and / or the outer peripheral portion where the metal layer 4 is not formed. Instead, it may be provided on the outer peripheral edge surface of the support 1. The uneven portion provided on the end face of the outer peripheral edge is shown by 9 in the figure.

In the present invention, in order to improve the adhesion of the protective layer 5, continuous or discontinuous uneven portions (7, 8, 9, 1) provided on the inner and outer peripheries of the support 1 and the end faces thereof.
0, 11) are not only the uneven portions of the support 1 itself from which the recording layer 3 and the metal layer 4 have been removed, but also the support 1 and the metal layer 4
It may be an uneven portion formed with a film thickness such that the unevenness of the support 1 is not lost by another layer provided between the support 1 and the recording layer 3 as shown in FIG. It may be another layer provided between the layers 4, for example, an uneven portion formed by an undercoat layer 6 as shown in FIG.

What is important in an optical information recording medium having a layer structure in which the protective layer 5 is provided on the metal layer 4 and using a dye in the recording layer 3 is that the protective layer 5 is below the metal layer 4. To maintain sufficient adhesion to the layer. In the prior art, the metal layer 4 is formed not on the entire surface of the support but on the inner peripheral portion or the outer peripheral portion, and a layer formed below the metal layer 4 has poor adhesion to the protective layer 5. Is required to be provided with unformed portions on the inner and outer peripheral portions similarly to the metal layer 4. Generally, a layer having poor adhesion to the protective layer 5 is unnecessary on the inner and outer peripheral portions. I had to remove that part.

In the present invention, however, a layer having poor adhesion is formed on the entire surface of the support and cannot be easily removed by a simple method, that is, the layer having poor adhesion to the protective layer 5 is the metal layer 4. If it becomes the uppermost layer underneath, the unevenness is provided on the support as described above. By providing it above, it becomes possible to have sufficient practicality in terms of durability and storage stability.

The protective layer material used in the present invention is preferably an ultraviolet curable resin capable of forming a film by a spinner coating method. This is because when the protective layer 5 is formed by the spinner coating method, the protective layer 5 is easily formed also on the end face of the support, and the adhesive force between the outer peripheral edge face of the support 1 and the protective layer 5 can be utilized to improve the adhesiveness. Can be made. Furthermore, from the viewpoint of productivity, a type in which the monomer is diluted with a solvent containing a substance that dissolves a material layer having poor adhesion to the protective layer 5 below the metal layer as the ultraviolet curable resin is preferable. The shape and size of the continuous or discontinuous uneven portion in contact with the protective layer 5 are preferably set according to the required durability and storage stability.

[0017]

The above-described optical information recording medium according to the present invention is an optical information recording medium having a recording layer of a dye having a layer structure in which at least a metal layer and a protective layer are provided on the support, and the outside of the recording area of the support. The inner peripheral portion and / or outer peripheral portion is provided with a portion having no metal layer, and further, if necessary, the outer peripheral edge face portion is provided with a concavo-convex portion continuously or discontinuously. Since the protective layer is formed so as to completely cover the protective layer, the contact between the protective layer and the uneven portion is smaller than in the case where the surface of the conventional support that contacts the protective layer at the inner and / or outer periphery is a flat surface. Property is improved, and thus the adhesion between the entire surface of the protective layer and the metal layer is improved, and the durability and storage stability of the optical information recording medium are improved.

Further, in the present invention, in the above-mentioned optical information recording medium, the uneven portion formed on the inner peripheral portion and / or the outer peripheral portion outside the recording area where the coating liquid of the protective layer finally adheres is dissolved to some extent. Alternatively, since the protective layer is provided with the coating liquid containing the substance to be swollen, the adhesiveness between the uneven portion and the protective layer is increased, and as a result, the adhesiveness between the dye recording layer and the metal layer or the metal layer and the protective layer is further increased. Can be improved.

At this time, if the support is a plastic support such as polycarbonate, the surface of the support is dissolved or swelled when the protective layer is applied to further improve the adhesion between the protective layer and the uneven portion. You can

The optical information recording medium having a dye recording layer such as CD-R, that is, the case where the metal layer functions as the reflecting layer has been described above, but the present invention is not limited to this. The metal layer may function as the recording layer.

[0021]

EXAMPLES Examples of the present invention will be specifically described below.

Example 1 A disk-shaped polycarbonate injection-molded support having a groove for tracking and having continuous uneven portions in the non-recording areas of the inner and outer circumferences was prepared by the following structural formula ( I) (N
K2929; manufactured by Nihon Senshokusho Co., Ltd.) is used to form a recording layer by a spinner coating method using a solution having a recording layer, and an Au layer of about 1500 Å is sputtered on the recording layer and Au is formed on the inner and outer peripheral portions by a mask. The layer was formed so as to have a non-formation region (Au was only 10 mm outside the peripheral edge of the hole of the support and 1.5 mm inside the outer peripheral edge).
Layers were formed). Then, an ultraviolet curable resin (TB-3070:
Film thickness of about 2μ by spinner coating method using ThreeBond
A protective layer of m was formed to obtain an optical information recording medium according to the present invention. At this time, the recording layer protruding from the Au metal layer was thoroughly washed off by the protective layer coating solution.

[Chemical 1]

Example 2 An optical information recording medium was prepared in the same manner as in Example 1 except that a support in which concave and convex grooves were formed on the outer peripheral edge of the polycarbonate support formed by injection molding was used. Got

Comparative Example 1 An optical information recording medium was produced in the same manner as in Example 1 except that the uneven portions were not provided in the non-recording areas of the inner peripheral portion and the outer peripheral portion.

Comparative Example 2 An optical information recording medium was prepared in the same manner as in Example 1 except that the Au layer was formed up to the outer edge of the support, and no concave and convex portions were provided in the non-recording areas of the inner peripheral portion and the outer peripheral portion. did.

Recording was performed on the optical information recording medium obtained above at a recording power of 6.0 mW and a linear velocity of 1.3 m / sec.
A storage test was carried out for 1 week in an environment of 80 ° C., and the C / N ratio before and after the storage test was measured. The results are shown in Table 1.

[0027]

[Table 1]

As is clear from these results, the optical information recording medium according to the present invention has excellent durability and storage stability, and can be easily prepared.

[0029]

According to the present invention, the inner peripheral portion outside the recording area of the support and / or the outer peripheral portion has a portion where the metal layer is not provided and the inner peripheral portion where the metal layer is not formed. as well as/
Alternatively, by forming a concavo-convex portion continuously or discontinuously on the outer peripheral portion and, if necessary, on the outer peripheral edge surface portion, and further forming a protective layer thereon, the protective layer and the metal layer lower layer can be formed. It is possible to provide an optical information recording medium having improved adhesion, improved durability and storage stability, high reliability, and excellent productivity.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of an optical information recording medium according to the present invention, in which continuous or discontinuous irregularities are formed on the inner peripheral portion and the outer peripheral portion of the support where the metal layer is not provided outside the recording area. A part is provided and a protective layer is formed on the part.

FIG. 2 is a cross-sectional view showing another example of an optical information recording medium according to the present invention, in which continuous or discontinuous uneven portions are formed on the inner peripheral portion where the metal layer is not formed and the outer peripheral edge surface portion of the support. The state where it is provided is shown.

FIG. 3 is a cross-sectional view showing still another example of an optical information recording medium according to the present invention, showing continuous or discontinuous uneven portions on the inner peripheral portion where the metal layer is not formed, the outer peripheral portion and the outside of the support. The state of being provided on the peripheral edge surface portion is shown.

FIG. 4 is a cross-sectional view showing an optical information recording medium according to still another example of the present invention, in which continuous or discontinuous uneven portions are not lost by the other layers between the support and the metal layer. A state in which the film is formed with such a film thickness is shown.

FIG. 5 is a cross-sectional view showing another example of an optical information recording medium according to the present invention, showing a state where continuous or discontinuous uneven portions are formed by a support and another layer between metal layers.

FIG. 6 is a plan view showing a discontinuous concave-convex portion formed on an inner peripheral portion and an outer peripheral portion of a support.

FIG. 7 is a plan view showing discontinuous uneven portions formed on an inner peripheral portion and an outer peripheral portion of a support.

FIG. 8 is a cross-sectional view showing a conventional optical information recording medium in which a recording layer made of a dye is formed by coating on a support.

FIG. 9: A recording layer made of a dye is formed by coating on a support,
It is sectional drawing which shows the conventional optical information recording medium which provided the metal layer on it.

FIG. 10 is a cross-sectional view showing a conventional optical information recording medium in which a recording layer made of a dye is coated and formed on a support, a metal layer is provided thereon, and a protective layer is further provided.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Support 2 Recording area 3 Recording layer 4 Metal layer 5 Protective layer 6 Undercoat layer 7 Inner peripheral irregularities 8 Outer peripheral irregularities 9 Outer peripheral end irregularities 10 Discontinuous irregularities 11 Continuous irregularities

Claims (5)

[Claims] 1. An optical information recording medium in which at least a metal layer and a protective layer are laminated on a support, and a portion where the metal layer is not provided on the inner peripheral portion and / or the outer peripheral portion outside the recording area of the support. And an uneven portion is continuously or discontinuously provided on the inner peripheral portion and / or the outer peripheral portion where the metal layer is not formed, and the protective layer is formed so as to cover the uneven portion. An optical information recording medium characterized in that. 2. An optical information recording medium comprising a support and at least a metal layer and a protective layer laminated on the support, the support having at least an inner peripheral portion outside the recording area, where the metal layer is not provided. And an inner peripheral portion where the metal layer is not formed,
An optical information recording medium, characterized in that an uneven portion is provided continuously or discontinuously on the outer peripheral edge surface of the support, and the protective layer is formed so as to cover the uneven portion. 3. The protective layer is formed by using a coating liquid containing a substance that dissolves or swells to some extent an uneven portion formed on the inner peripheral portion and / or the outer peripheral portion outside the recording area that finally comes into contact. The optical information recording medium according to claim 1, wherein the optical information recording medium is an optical information recording medium. 4. An optical information recording medium comprising a plastic support /
Recording layer / metal layer / protective layer, plastic support / subbing layer / recording layer / metal layer / protective layer, or plastic support /
The optical information recording medium according to claim 1, wherein the optical information recording medium is composed of a metal layer / protective layer. 5. An optical information recording medium comprising a plastic support /
4. A recording layer / metal layer / protective layer comprising a dye, or a plastic support / subbing layer / a recording layer / metal layer / protective layer comprising a dye, according to any one of claims 1 to 3. The optical information recording medium according to the item 1.