JPH0981964A - Optical disk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to dispose first and second printing layers in the wide areas of first and second optical disk base bodies having transparency by providing the surfaces of the respective protective layers of the first and second disk base bodies with the first and second printing layers on which symbols are printed. SOLUTION: The first optical disk base body 5 and the second disk base body 6 are provided with the disk base bodies 5A, 6A formed with a transparent synthetic resign material, such as polycarbonate or polymethyl methacrylate, into a disk shape. This optical disk is constituted by having information signal layers 5B, 6B which are formed on these base bodies 5A, 6A and are recorded with information signals, semi-transmissible reflection films 5D, 6D which are formed on these signal layers 5B, 6B and the protective layers 5C, 6C which are formed on the information signal layers 5B, 6B to coat these layers. The information signals recorded on the information signal layers 5B, 6B of the first optical disk base body 5 of the optical disk 1 constituted in such a manner are read in arrow A direction by a reproducing device (not shown in Fig.) and the information signals recorded on the information signal layer 6B of the second optical disk base body 6 are read in arrow B direction by the reproducing device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc provided with a label print for displaying symbols such as recorded contents and patterns of information signals recorded in an information signal layer.

[0002]

2. Description of the Related Art Generally, an optical disc is a disc substrate formed of a transparent synthetic resin material such as polycarbonate (PC) or polymethylmethacrylate (PMMA), and an information signal layer formed on the main surface of the disc substrate. And a protective layer formed on the information signal layer to mechanically and chemically protect the information signal layer.

On the optical disc, the recorded contents of the information signal recorded in the information signal layer and the display of symbols such as patterns (hereinafter referred to as a label) are located on the back surface of the information signal reading surface side. Printing is performed on the layer by a printing method such as screen printing, pad printing, or offset printing. For example, in the case of a single-sided recording / reproducing format optical disc, a label is directly printed on the protective layer located on the back surface on the reading side of the information signal.

Along with the increase in the capacity of information signals, there has been proposed an optical disk of double-sided recording / reproducing format which is constructed by laminating optical disk substrates of single-sided recording / reproducing format of information signals. In the case of this double-sided recording / reproducing format optical disc, printing is performed directly in a narrow area near the central portion on the read surface of the information signal so as not to hinder the reading of the information signal of the information signal layer, or A film body, which is sufficiently smaller than the diameter dimension and has a label printed thereon, is attached.

[0005]

As described above, an optical disc constructed by laminating optical disc substrates is
Since the information signal reading surface is on both sides, printing on the information signal reading surface hinders the reading of the information signal. That is, in this optical disc, when a reproducing operation such as reading of an information signal is performed by the reproducing apparatus, inconvenience such as an error of reading the information signal occurs due to printing performed on the reading surface of the information signal.

Therefore, in this optical disk, it is necessary to print a label for displaying the recorded contents of the information signal, symbols such as patterns, etc. in an area that does not adversely affect the reading of the information signal, and the label is printed. There was a problem that the possible area was narrow.

Therefore, according to the present invention, in an optical disc constituted by laminating optical disc substrates, a print layer on which symbols such as recorded contents and patterns are printed is arranged in a wide area of the information signal reading surface of the optical disc substrate. It is an object of the present invention to provide an optical disc that can be used.

[0008]

In order to achieve the above-mentioned object, an optical disc according to the present invention has an optical disc substrate, an information signal layer formed on the optical disc substrate, and a protective layer for protecting the information signal layer. A first optical disc substrate, an optical disc substrate, an information signal layer formed on the optical disc substrate, and a protective layer for protecting the information signal layer, and the protective layer side is superposed on the protective layer side of the first optical disc substrate. And a second optical disc substrate to be joined together. Then, this optical disk is formed on the respective protective layers of the first optical disk base and the second optical disk base,
A first printed layer and a second printed layer on which the symbols are printed are respectively arranged. Further, the first optical disk substrate and the second optical disk substrate have a transparency such that the first printed layer and the second printed layer can be visually recognized.

The optical disc constructed as described above is the first
The first printed layer, on which the symbol is printed and which is disposed on the protective layer of the optical disc substrate, is visible through the first optical disc substrate. Further, in this optical disc, the second printed layer, on which the symbol is printed and which is arranged on the protective layer of the second optical disc substrate, is visually recognized through the second optical disc substrate. Therefore, the first printing layer and the second printing layer arranged on this optical disc do not prevent the reading of the information signal of each information signal layer of the first optical disc substrate and the second optical disc substrate.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Specific embodiments of the present invention will be described below with reference to FIGS. As shown in FIGS. 1 and 2, this optical disc 1 has a first optical disc substrate 5 on which an information signal is recorded.
And a second optical disc substrate 6 on which an information signal is recorded and which is superposed on and bonded to the first optical disc substrate 5.
The first optical disc substrate 5 and the second optical disc substrate 6 are provided with a first printing layer 7 and a second printing layer 8, respectively.

As shown in FIG. 3, the first optical disk substrate 5 and the second optical disk substrate 6 are formed in a disk shape from a transparent synthetic resin material such as polycarbonate (PC) or polymethylmethacrylate (PMMA). Disc substrates 5A, 6A, and information signal layers 5B, 6B formed on the disc substrates 5A, 6A and recording information signals,
The semi-transmissive reflective film 5 formed on the information signal layers 5B and 6B
D and 6D, and protective layers 5C and 6C formed on the information signal layers 5B and 6B in order to mechanically and chemically protect the information signal layers 5B and 6B.

The first optical disk substrate 5 and the second optical disk substrate 6 are formed such that the disk substrates 5A and 6A have a thickness of about 0.6 mm, and have a predetermined transmittance (hereinafter referred to as transparency). ) Has. Protective layer 5C, 6C
Has a thickness of about 40 μm and has a predetermined transparency. The semi-transmissive reflective films 5D and 6D are about 50
It has a transparency of about%.

Then, the first optical disk substrate 5 and the second optical disk substrate 5
The optical disc substrate 6 of No. 1 has the first layer on the protective layers 5C and 6C.
The printed layer 7 and the second printed layer 8 are respectively disposed. The first print layer 7 is provided on the protective layer 5C of the first optical disc substrate 5, and is a symbol such as the recorded content of the information signal recorded in the information signal layer 5B of the first optical disc substrate 5 or a pattern. Is composed of a main printing layer 7A in which the printing of the label displaying is reversed and a sub printing layer 7B provided on the main printing layer 7A, which is so-called solid-painted with a single color ink such as white. There is.

The second printed layer 8 is provided on the protective layer 6C of the second optical disc substrate 6, and the recorded contents and patterns of the information signal recorded on the information signal layer 6B of the second optical disc substrate 6 are provided. From the main printing layer 8A on which the printing of the label displaying symbols such as is reversed, and the sub-printing layer 8B provided on the main printing layer 8A, which is so-called solid-painted with a single color ink such as white It is configured.

In the second optical disc substrate 6, the protective layer 6C side is on the protective layer 5C side of the first optical disc substrate 5, and the adhesive 1
They are superposed and joined via 0. That is,
The optical disc 1 has a protective layer 5C of the first optical disc substrate 5.
The first printed layer 7 provided above and the second printed layer 8 provided on the protective layer 6C of the second optical disc substrate 6 are overlapped and joined.

The first optical disk substrate 5 and the second optical disk substrate 6 have a predetermined size such that the label symbols printed on the first printing layer 7 and the second printing layer 8 can be seen through. As long as it has transparency, the optical disk substrates 5A and 6A and the protective layers 5C and 6C may be appropriately colored as necessary.

The optical disk 1 configured as described above is
The information signal recorded on the information signal layer 5B of the first optical disc substrate 5 by a reproducing device (not shown) is read out in the direction of arrow A shown in FIG. 3, and the information signal layer of the second optical disc substrate 6 by the reproducing device. The information signal recorded in 6B is read in the direction of arrow B shown in FIG.

In this optical disc 1, the label printed on the first printing layer 7 is the first optical disc substrate 5
The label printed on the second printing layer 8 is visually recognized by being transmitted through the protective layer 5C, the semi-transmissive reflective film 5D, and the optical disc substrate 5A, respectively, and the label printed on the second printing layer 8 is the second optical disc substrate 6
And is visible through the protective layer 6C, the semi-transmissive reflective film 6D, and the optical disk substrate 6A, which constitute the above.

That is, the first printing layer 7 and the second printing layer 8 which are applied by reversing the printing of the label are transmitted through the first optical disk substrate 5 and the second optical disk substrate 6 to the label. Is normally recognized.

As described above, according to the optical disc 1 of the embodiment, the first printing layer 7 and the second printing layer 7 are provided on the respective protective layers 5C and 6C of the first optical disc substrate 5 and the second optical disc substrate 6 having transparency. By arranging the first print layer 7 and the second print layer 8, the first print layer 7 and the second print layer 8 are arranged in a wide area of the information signal read surface without causing any inconvenience in reading the information signal. It is possible to do.

In addition, according to this optical disc 1, the first
Printed layer 7 and second printed layer 8 are information signal layers 5B and 6 of the first optical disc substrate 5 and the second optical disc substrate 6, respectively.
Since the irregularities, so-called pits, which are the information signals formed on B are transmitted and visually recognized respectively, the labels of the first printing layer 7 and the second printing layer 8 are interesting in terms of design due to the interference of light by the pits. The effect is also obtained.

The optical disc 1 of the above-mentioned embodiment is
The first printing layer 7 and the second printing layer 8 are arranged between the first optical disk substrate 5 and the second optical disk substrate 6, respectively. Needless to say, the configuration may be such that only one of the two printing layers 8 is provided.

[0023]

As described above, according to the optical disc of the present invention, the first optical disc substrate having the transparency and the second optical disc substrate having the transparency are provided.
A first printed layer and a second printed layer having a symbol printed thereon are respectively disposed on the respective protective layers of the optical disc substrate of FIG.
The optical disc substrate and the second optical disc substrate can be arranged in a wide area.

[Brief description of drawings]

FIG. 1 is an exploded schematic view showing an optical disc according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view showing the optical disc.

FIG. 3 is a longitudinal sectional view of a main part showing the optical disc.

[Explanation of symbols]

 1 Optical Disc 5 First Optical Disc Base 5A Optical Disc Substrate 5B Information Signal Layer 5C Protective Layer 5D Semi-Transparent Reflective Film 6 Second Optical Disc Base 6A Optical Disc Substrate 6B Information Signal Layer 6C Protective Layer 6D Semi-Transparent Reflective Film 7 First Printing Layer 7A Main printing layer 7B Sub printing layer 8 Second printing layer 8A Main printing layer 8B Sub printing layer

Claims (2)

[Claims] 1. A first optical disc base having an optical disc substrate, an information signal layer formed on the optical disc substrate, and a protective layer for protecting the information signal layer, an optical disc substrate, and an information signal formed on the optical disc substrate. A second optical disc substrate having a layer and a protective layer for protecting the information signal layer, the protective layer side being superposed on and bonded to the protective layer side of the first optical disc substrate; the first optical disc substrate and the second optical disc substrate. A first printing layer and a second printing layer, which are respectively provided on respective protective layers with the optical disc substrate and have a symbol printed thereon, and the first optical disc substrate and the second optical disc substrate have the first printing layer. The layer and the second printed layer have a visible transparency, and the first printed layer and the second printed layer are visible from the first optical disc substrate and the second optical disc substrate, respectively. An optical disc characterized by being recorded. 2. The first printing layer and the second printing layer,
Consists of a main printing layer disposed on the protective layers of the first optical disc substrate and the second optical disc substrate and printed with the symbols reversed, and a monochromatic sub-printing layer disposed on the main printing layer. The optical disc according to claim 1, wherein the optical disc is recorded.