JP2002216398A - Manufacturing method of optical recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To recycle an optical recording medium such as a useless optical disk, a useless optical memory card or the like without crushing it. SOLUTION: The following characteristic manufacturing method of the optical recording medium is provided: when the optical recording medium such as the useless optical disk, the useless optical memory card or the like is recycled without crushing it, a new optical recording medium is manufactured by bonding the plastic substrate of the useless optical recording medium, as a dummy plastic substrate for reinforcement, and the plastic substrate of an optical recording medium to be newly manufactured together.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method of manufacturing an optical recording medium by reusing a resin substrate of an optical recording medium such as an optical disk or an optical card which is no longer required.

[0002]

2. Description of the Related Art Generally, a compact disc (CD) is used.
Disc-shaped optical discs such as DVDs and digital versatile discs (DVDs) and optical recording media such as substantially rectangular optical cards record and / or record information such as video information, audio information, and computer programs in high density and large capacity. It is often used because it can be played back and accessed at high speed.

FIG. 5 is a diagram schematically showing a compact disk (CD) among commonly used optical recording media, and FIG. 6 is a diagram schematically showing a generally used optical recording medium. It is the figure which showed typically the digital versatile disk (DVD), (a) shows the case where the signal surface has one layer, and (b) is the figure which showed the case where the signal surface has two layers.

First, as shown in FIG. 5, among commonly used optical recording media, a compact disk (CD) 10 is made transparent by molding using a thermoplastic transparent resin such as a polycarbonate resin. The resin substrate 11 is formed in a disk shape. At this time, the outer diameter of the disc-shaped transparent resin substrate 11 is 12 cm, the thickness is 1.2 mm, and the center hole 11 is formed.
The hole diameter of a is formed to be 15 mm.

Also, one surface 11b of the transparent resin substrate 11
Is formed flat as an incident surface on which a laser beam LB emitted from an objective lens in an optical pickup (not shown) is incident, and a signal surface is formed on the other surface 11c side opposite to the one surface 11b. .

Here, the other surface 11 of the transparent resin substrate 11
On the signal surface formed on the c-side, tracks obtained by converting audio information and the like into a plurality of pit rows having irregularities are engraved spirally or concentrically, and the Al reflection layer 1 is formed on the plurality of pit rows.
2 has a thickness of about 0.05 μm. Also, Al
A protective layer 13 is formed on the reflective layer 12 to a thickness of about 5 μm,
Further, a label layer 14 is printed on the protective layer 13 by about 10 μm.

Then, one surface 11 of the transparent resin substrate 11
b, a laser beam LB is emitted, and the laser beam LB is reflected by an Al reflection layer 12 formed on a plurality of pit rows carved on the other surface 11c, and the returned reflected light is reflected by an optical pickup (not shown). The sound information and the like are reproduced by detecting with the photo detector in the parentheses.

Accordingly, the compact disk (CD) 10
Is widely used as a reproduction-only optical disk capable of reproducing audio information and the like. A computer program is commercially available as a CD-ROM.

Next, as shown in FIGS. 6A and 6B, digital versatile discs (DVDs) 20, 30 among commonly used optical recording media are:
An optical disk in which the amount of information is further increased than the compact disk (CD) 10 described above, and the wavelength of a laser beam LB emitted from an objective lens in an optical pickup (not shown) is accordingly reduced. (C
D) Since it is shorter than the case of 10 and the depth of focus on the signal surface of the objective lens becomes shallower, the disc-shaped transparent resin substrate needs to be thinner from the incident surface of the laser beam LB to the signal surface.

In the case of a digital versatile disk (DVD) 20 having a single-layer signal surface, FIG.
As shown in the figure, the signal surface is formed and the thickness is 0.6 mm.
A transparent resin substrate 21 having a thickness of 0.6 mm and a dummy resin substrate 25 having a thickness of 0.6 mm serving as a reinforcement for the transparent resin substrate 21 and having a thickness of 0.6 mm are bonded to each other by using an ultraviolet-curable adhesive, and the total thickness is set. Are configured as a 1.2 mm bonded optical disk.

On the other hand, in the case of a digital versatile disk (DVD) 30 having a two-layer signal surface, as shown in FIG. 6B, a disk-shaped disk having a signal surface and a thickness of 0.6 mm is formed. The first and second transparent resin substrates 31 and 35 are bonded to each other using a transparent ultraviolet-curable adhesive so that the signal surfaces are located inside each other, thereby forming a bonded optical disk having a total thickness of 1.2 mm. ing.

More specifically, as shown in FIG. 6A, in a digital versatile disk (DVD) 20 having a single-layer signal surface, the signal is transparent by molding using a thermoplastic transparent resin such as a polycarbonate resin. Resin substrate 21
And a dummy resin substrate 25 is formed in a disk shape. Both of these resin substrates 21 and 25 have an outer diameter of 12 cm, a thickness of 0.6 mm, and a hole diameter of the center holes 21a and 25a of 15 mm.
Is formed.

Also, one surface 21b of the transparent resin substrate 21
Is formed flat as an incident surface on which a laser beam LB emitted from an objective lens in an optical pickup (not shown) is incident, and a signal surface is formed on the other surface 21c side opposite to the one surface 21b. .

The dummy resin substrate 25 has two surfaces 25b,
25c are formed flat, and no signal surface is formed.

Here, the other surface 21 of the transparent resin substrate 21
The signal surface formed on the c side is a compact disc (CD)
As in the case of 10, the Al reflection layer 22 is formed on a plurality of uneven pit rows by a thickness of about 0.05 μm. Also,
A protective layer 23 is formed on the Al reflective layer 22 to a thickness of about 5 μm.

Further, a dummy resin substrate 25 is bonded on the protective layer 23 via an adhesive layer 24 of about 40 μm, and the label layer 2 is placed on the dummy resin substrate 25.
6 is printed about 10 μm.

When the signal surface is a single-layer digital versatile disk (DVD) 20, as in the case of the compact disk (CD) 10, the transparent surface is transparent by the laser beam LB applied to one surface 21 b of the transparent resin substrate 21. The signal surface formed on the other surface 21c side of the resin substrate 21 is reproduced, and this signal surface is designed to have a higher density.

As shown in FIG. 6B, a digital versatile disk (DVD) 3 having a two-layer signal surface is used.
0, the first transparent resin substrate 31 and the second transparent resin substrate 31 are formed by molding using a thermoplastic transparent resin such as a polycarbonate resin.
A transparent resin substrate 35 is formed in a disk shape, and both of these resin substrates 31 and 35 have an outer diameter of 12 cm and a thickness of 0.1 mm.
6 mm, and the hole diameter of the center holes 31a and 35a is 15 mm.

Further, one surface 3 of the first transparent resin substrate 31
1b is formed flat as an incident surface on which a laser beam LB emitted from an objective lens in an optical pickup (not shown) is incident, and the other surface 31c opposite to the one surface 31b.
A signal surface is formed on the side.

Further, the second transparent resin substrate 35 has one surface 3
The signal surface is formed on the 5b side, and the other surface 35c opposite to the one surface 35b is formed flat.

Here, the signal surface formed on the other surface 31c side of the first transparent resin substrate 31 has a spiral or a track in which video information, audio information, a computer program, etc. are converted into a plurality of pit rows having irregularities. An Au semi-transmissive reflection layer 32 that is concentrically carved and that semi-transmits the laser beam LB on the plurality of pit rows is formed with a film thickness of about 0.02 μm.

The other surface 3 of the second transparent resin substrate 35
Also on the signal surface formed on the 5c side, tracks obtained by converting video information, audio information, computer programs, etc. into a plurality of pit rows having irregularities are engraved spirally or concentrically.
In addition, the Al reflection layer 34 has a thickness of about 0.05 on the plurality of pit rows.
A film of about μm is provided.

Then, the first and the second transparent resin layers 33 are interposed so that the signal surface side of the first transparent resin substrate 31 and the signal surface side of the second transparent resin substrate 35 are inside each other. The two transparent resin substrates 31 and 35 are attached to each other, and the label layer 36 is printed on the second transparent resin substrate 35 by about 10 μm.

In the case of a digital versatile disk (DVD) 30 having a two-layered signal surface, a laser beam LB is irradiated from one surface 31b of the first transparent resin substrate 31 to form a single layer by the laser beam LB. One of the signal surfaces is selected and reproduced according to the difference between the light transmittance to the signal surface of the eye and the light transmittance to the signal surface of the second layer.

Furthermore, compact discs (CDs) and digital versatile discs (DVDs) are not limited to reproduction as described above, but are not shown in the drawings, but can be written only once, such as CD-R, DVD-R, and the like. Rewritable C
Optical discs such as D-RW, DVD-RW, and DVD-RAM have also begun to spread gradually. In the case of these recordable and reproducible optical discs, tracks formed by pairs of concave and convex grooves and lands are spiral or concentric. And a recording layer is formed on the uneven grooves and lands.

Also, an optical card having a substantially rectangular shape can be used as a substitute for a conventional magnetic card as an ID card for personal authentication, a credit card, or a prepaid card because of the advantage that a large amount of information can be recorded and reproduced.

As optical disks and optical cards have become widespread in this way, the number of defective products, stock disposal products, returned products from the market, used products, etc. generated in the manufacturing process has increased in large quantities. The resulting optical recording medium was disposed of by incineration or landfill after being subjected to crushing treatment as waste.

However, such a disposal method is a waste of resources and is not a preferable method in view of the problem of environmental pollution due to incineration and landfill. From the viewpoint of protecting the global environment, it is important to collect and reuse used materials from discarded optical recording media. At this time, among the materials used for the optical recording medium, the most used material is a disc-shaped or substantially rectangular resin substrate. Therefore, it is most important to recover and reuse the resin material used for the resin substrate.

Most of the resin substrates used for the optical recording medium are made of polycarbonate resin, polymethyl methacrylate resin, etc. from the viewpoint of processability, productivity and material cost.
Thermoplastic transparent resins such as alicyclic polyolefin resins are used. Among them, polycarbonate resin is most frequently used. For example, compact disc (CD)
, The polycarbonate resin accounts for 98% or more in terms of weight.

Here, a method for recovering the resin used for the resin substrate from the optical recording medium is described in, for example,
No. 63942 discloses that after an optical recording medium is crushed,
A method is disclosed in which a reflective layer is dissolved in an acidic solution, and a protective layer is peeled from a transparent resin substrate to recover a resin used for the transparent resin substrate.

In JP-A-4-360035 and JP-A-7-286064, after the optical recording medium is crushed, the reflective layer and the protective layer are removed in a basic solution and used for a resin substrate. A method for recovering the resin that has been described.

[0032]

In the prior art described in the above-mentioned JP-A-6-63942, JP-A-4-360035, and JP-A-7-286064, the discarded optical disc is crushed. After that, the reflective layer and the protective layer are removed with an acid or a basic solution, and only the thermoplastic resin used for the transparent resin substrate is separated and collected. Further, the recovered resin must be crushed and kneaded, pelletized as a molding material, and processed again according to the application. Such a process has a problem that it requires time, time and cost.

Therefore, there is a demand for a method of manufacturing an optical recording medium that can be reused for a newly manufactured optical recording medium without grinding an optical recording medium such as an optical disk or an optical card that is no longer needed.

[0034]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and is intended to provide a new method for reusing (recycling) an unnecessary optical recording medium such as an optical disk or an optical card without grinding. A method for manufacturing an optical recording medium, comprising: bonding an unneeded resin substrate of an optical recording medium to a resin substrate of an optical recording medium to be manufactured as a dummy resin substrate for reinforcement to manufacture an optical recording medium. Is what you do.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for manufacturing an optical recording medium according to the present invention will be described below with reference to FIGS.
Embodiment> to <Fourth Embodiment> will be described in detail in this order.

In the method for manufacturing an optical recording medium according to the present invention,
When reusing (recycling) an optical recording medium such as an optical disk or optical card that is no longer needed without grinding it, the resin substrate of the optical recording medium that is no longer needed is reinforced with the resin substrate of the optical recording medium that is newly manufactured. The optical recording medium is manufactured by bonding together as a dummy resin substrate for use. At this time, a resin substrate using a thermoplastic transparent resin is taken out of the optical recording medium that is no longer needed, and the resin substrate is removed. The substrate is appropriately cut in the thickness direction as necessary to provide a reinforcing dummy resin substrate for an optical recording medium.

In the following first to fourth embodiments, the same components as those described in the prior art will be denoted by the same reference numerals.

<First Embodiment> FIGS. 1A and 1B are schematic views for explaining a method of manufacturing an optical recording medium according to a first embodiment of the present invention. FIG. FIG. 7B is a view showing a process of taking out a resin substrate from FIG. 5, and FIG. 7B is a diagram showing an ultra-high-density optical disk newly manufactured by reusing an unnecessary CD resin substrate.

First, as shown in FIG. 1A, only the transparent resin substrate 11 is taken out of the unnecessary CD (compact disk) 10. Here, the transparent resin substrate 1
The Al reflective layer 12, the protective layer 13, and the label layer 14 are peeled off from the signal surface formed on the other surface 11c side of the substrate 1 by an acidic solution, a basic solution, or a cutting process, and only the unnecessary transparent resin substrate 11 is removed. Have gained.

Further, the transparent resin substrate 11 formed to have a thickness of 1.2 mm is reused as it is, or the other surface 11c is cut by about 0.1 to 0.3 mm if necessary. To form a required thickness.

At this time, the other surface 11 of the transparent resin substrate 11
The entire surface of the c-side is roughened with a cutting or polishing tape or the like so that irregularities of about 1 to 100 μm are formed, and the transparent resin substrate 11 in this state is prepared as a reinforcing dummy resin substrate.

Next, as shown in FIG. 1B, when an unnecessary CD (compact disk) resin substrate is reused to newly manufacture an ultra-high-density optical disk 50, it becomes unnecessary. A cured resin layer for signal surface 51 on which an ultra-high-density signal surface is formed is adhered to the other surface 11c side of the transparent resin substrate 11 by using a well-known 2P method. Here, tracks obtained by converting video information, audio information, a computer program, and the like into a plurality of pit rows having irregularities are formed in the signal surface cured resin layer 51 in a spiral or concentric manner at a very high density. The signal surface of the cured resin layer for signal surface 51 is formed below the other surface 11 c of the transparent resin substrate 11. The unnecessary transparent resin substrate 11 functions as a reinforcing dummy resin substrate for the cured resin layer 51 for the signal surface.

Incidentally, a method of forming a plurality of pit rows serving as signal surfaces on the cured resin layer for signal surface 51 by the 2P method is described in Japanese Patent Application Laid-Open No. 6-270165. An ultraviolet-curable resin is dropped on (not shown), and the other surface 11c of the unnecessary transparent resin substrate 11 is pressed from above the ultraviolet-curable resin to cure the ultraviolet-curable resin, thereby forming a signal surface. The cured resin layer 51 for a signal surface is formed. At this time, the transparent resin substrate 1
The other surface 11c of 1 has a surface of 1 to 1 as described above.
Since the surface is roughened by irregularities of about 100 μm, the cured resin layer for signal surface 51 can be satisfactorily adhered to the other surface 11 c of the transparent resin substrate 11.

Next, an Al reflective film 52 is formed on the signal surface of the cured resin layer for signal surface 51 to a thickness of about 0.05 μm, and the thickness is reduced to about 0 μm via a transparent adhesive layer 53 of about 40 μm. A disc-shaped transparent film 54 of about 1 mm is attached. At this time, the center hole 11a of the transparent resin substrate 11 is
And the center hole 54a of the transparent film 54 are concentric. Thereafter, the label layer 55 is printed on one surface 11b of the reinforcing dummy resin substrate 11.

The ultra-high-density optical disk 50 manufactured as described above is provided with an optical pickup (not shown).
Blue laser beams B and LB from a high NA (numerical aperture) objective lens provided in one side 54b of a transparent film 54
, It is possible to reproduce a plurality of pit rows formed at a very high density on the signal surface of the cured resin layer for signal surface 51.

The above-described ultra-high-density optical disk 50
Has been described with a plurality of pit rows formed exclusively for reproduction. However, the present invention is not limited to this.
Is formed for recording / reproducing, a track having a pair of concave and convex grooves and lands is spirally or concentrically formed on the signal surface cured resin layer 51 in an ultra-high density by a 2P method, and The recording layer may be formed on the uneven grooves and lands.

<Second Embodiment> FIGS. 2A and 2B are schematic views for explaining a method of manufacturing an optical recording medium according to a second embodiment of the present invention. FIG. FIG. 7B is a diagram illustrating a process of taking out a resin substrate from FIG. 5, and FIG. 7B is a diagram illustrating a DVD having a single layer of signal surface newly manufactured by reusing an unnecessary CD resin substrate.

First, as shown in FIG. 2A, only the transparent resin substrate 11 is taken out of the unnecessary CD (compact disk) 10. Here, similarly to the first embodiment, the Al reflective layer 12, the protective layer 13, and the label layer 1 from the signal surface formed on the other surface 11c side of the transparent resin substrate 11.
4 is removed by an acidic solution, a basic solution, a cutting process, or the like to obtain only the unnecessary transparent resin substrate 11.

Here, the difference from the first embodiment is as follows.
The amount of cutting into the transparent resin substrate 11 formed to a thickness of 0.5 mm is increased, and the other surface 11c of the transparent resin substrate 11 is set to approximately 0.6 mm.
It is formed to the required thickness by cutting about mm.

At this time, the other surface 11 of the transparent resin substrate 11
The entire surface of the c-side is roughened with a cutting or polishing tape or the like so that irregularities of about 1 to 100 μm are formed, and the transparent resin substrate 11 in this state is prepared as a reinforcing dummy resin substrate.

Next, as shown in FIG. 2 (b), a DVD (digital versatile disk) 60 having a single-layer signal surface is newly formed by reusing an unnecessary resin substrate of a CD (compact disk). 0.6mm thickness when manufacturing
On the other surface 61c side of the disc-shaped transparent resin substrate 61, a plurality of uneven pit rows are cut, and A is formed on the plurality of pit rows.
l A reflective layer 62 is formed to a thickness of about 0.05 μm.
A protective layer 63 is formed on the reflective layer 62 to a thickness of about 0.5 μm.

Next, an unnecessary thickness of about 0.6 mm is formed on the protective layer 63 via an adhesive layer 64 of about 40 μm.
The transparent resin substrate 11 is bonded as a reinforcing dummy resin substrate. At this time, the reinforcing dummy resin substrate 11
As described above, if the surface 11c whose entire surface is roughened by irregularities of about 1 to 100 μm is used as the bonding surface to the transparent resin substrate 61, the two resin substrates 61 and 11 can be satisfactorily adhered to each other. Of course, the center alignment is performed so that the center hole 61a of the transparent resin substrate 61 and the center hole 11a of the reinforcing dummy resin substrate 11 are concentric. Thereafter, a label layer 65 is printed on one surface 11b of the reinforcing dummy resin substrate 11.

The DVD (digital versatile disc) 60 having a single signal surface and newly manufactured as described above is provided with a laser beam LB from an objective lens provided in an optical pickup (not shown) by a transparent resin substrate. By irradiating one surface 61b of 61, the signal surface formed on the other surface 61c side of the transparent resin substrate 61 can be reproduced.

It should be noted that a newly manufactured DVD having a single-layer signal surface is used.
In the above description, the DVD 60 is formed of a plurality of pit rows for read-only use. However, the present invention is not limited to this. A groove and a land having irregularities may be formed on the surface 61c, and a recording layer may be formed on the groove and the land.

<Third Embodiment> FIGS. 3A and 3B are schematic views for explaining a method of manufacturing an optical recording medium according to a third embodiment of the present invention. FIG. (B) shows a step of taking out a resin substrate from a single-layer DVD, and (b) reusing the resin substrate of a single-layer DVD having an unnecessary signal surface to newly produce a single-layer DVD. FIG.

First, as shown in FIG. 3A, a transparent resin substrate 21 and a dummy resin substrate 25 are taken out of a DVD (digital versatile disk) 20 having an unnecessary signal surface as a single layer. Here, the transparent resin substrate 21
The adhesive layer 24 which is a boundary between the transparent resin substrate 21 and the dummy resin substrate 25 is cut using a knife or the like.
And the dummy resin substrate 25, and thereafter, the Al reflective layer 22 and the protective layer 23 are separated from the signal surface formed on the other surface 21c side of the transparent resin substrate 21 by an acidic solution or a basic solution or cutting. Then, the label layer 26 on the dummy resin substrate 25 is peeled off, and the unnecessary transparent resin substrate 21 and dummy resin substrate 25 are obtained.

At this time, the other surface 21c of the transparent resin substrate 21 formed at 0.6 mm and the one surface 25b (or the other surface 25c) of the dummy resin substrate 25 formed at 0.6 mm are Rough the entire surface with cutting or polishing tape, etc. so that irregularities of about 1 to 100 μm can be made,
The transparent resin substrate 21 or the dummy resin substrate 25 in this state is prepared as a reinforcing dummy resin substrate.

Next, as shown in FIG. 3 (b), the unnecessary resin substrate is reused to newly form a single-layer signal plane.
When manufacturing a VD (Digital Versatile Disc) 70, a plurality of pit rows having irregularities are cut on the other surface 71c side of a disc-shaped transparent resin substrate 71 having a thickness of 0.6 mm, as in the second embodiment. Then, an Al reflective layer 72 is formed on the plurality of pit rows at a thickness of approximately 0.05 μm, and a protective layer 73 is formed on the Al reflective layer 72 at a thickness of approximately 0.5 μm.

Next, an unnecessary transparent resin substrate 21 or dummy resin substrate 25 having a thickness of 0.6 mm is pasted as a reinforcing dummy resin substrate on the protective layer 73 via an adhesive layer 74 of about 40 μm. I'm matching. At this time, as described above, the reinforcing dummy resin substrate 21 or 25 may have the surface 21c or the surface 25b (or 25c) whose entire surface is roughened by unevenness of about 1 to 100 μm as an adhesive surface to the transparent resin substrate 71. , Two resin substrates (71, 21) or (71, 21)
5) Good contact can be obtained. Of course, the transparent resin substrate 71
Center hole 71a and the reinforcing dummy resin substrate 21 or 25
The center is adjusted so that the center hole 21a or 25a is concentric. After this, the reinforcing dummy resin substrate 2
The label layer 75 is printed on 1 or 25.

The DVD (digital versatile disk) 70 having a single-layer signal surface manufactured as described above is provided with a laser beam LB from an objective lens provided in an optical pickup (not shown) on a transparent resin substrate. By irradiating one surface 71b of 71, the signal surface formed on the other surface 71c side of the transparent resin substrate 71 can be reproduced.

It is to be noted that a newly manufactured DVD having a single-layer signal surface is used.
Although 70 is described as being formed by a plurality of pit rows for reproduction only, the present invention is not limited to this. When the DVD 70 is formed for recording and reproduction as described in the conventional example, the other side of the transparent resin substrate 71 is used. A groove and a land with irregularities may be formed on the surface 71c, and a recording layer may be formed on the groove and the land.

<Fourth Embodiment> FIGS. 4A and 4B are schematic diagrams for explaining a method of manufacturing an optical recording medium according to a fourth embodiment of the present invention. FIG. (B) shows a step of taking out a resin substrate from a two-layer DVD, and (b) reusing an unnecessary two-layer DVD resin substrate to newly produce a single-layer DVD. FIG.

First, as shown in FIG. 4A, the first transparent resin substrate 31 and the second transparent resin substrate 35 are taken out of a DVD (digital versatile disk) 30 having an unnecessary signal surface having two layers. ing. Here, a cut is made using a knife or the like in a transparent adhesive layer 34 which is a boundary between the first transparent resin substrate 31 and the second transparent resin substrate 35,
The first transparent resin substrate 31 and the second transparent resin substrate 35 are separated from each other. After that, the Au semi-transmissive reflection layer 32 and the second transparent resin layer 32 are separated from the signal surface formed on the other surface 31 c side of the first transparent resin substrate 31. The Al reflective layer 34 is separated from the signal surface formed on the one surface 35b side of the resin substrate 35 by an acidic solution, a basic solution, cutting, or the like, and further, the label layer 36 on the second transparent resin substrate 35 is removed. By peeling off, the first and second transparent resin substrates 31 and 35 which are no longer needed are obtained.

At this time, the other surface 31c of the first transparent resin substrate 31 formed at 0.6 mm and one surface 35b (or the other surface 35c) of the second transparent resin substrate 35 formed at 0.6 mm 2) The entire surface is roughened with a cutting or polishing tape or the like so that irregularities of about 1 to 100 μm are formed on the side, and the first transparent resin substrate 31 or the second transparent resin substrate 35 in this state is used as a reinforcing dummy resin substrate. Have it ready.

Next, as shown in FIG. 4B, the unnecessary resin substrate is reused to newly form a D-layer having a single signal surface.
When manufacturing a VD (digital versatile disk) 80, the other surface 81 of a 0.6 mm-thick disk-shaped transparent resin substrate 81 is used as in the second and third embodiments.
A plurality of uneven pit rows are carved on the c side, an Al reflection layer 82 is formed on the plurality of pit rows to a thickness of about 0.05 μm, and a protective layer 83 is formed on the Al reflection layer 82 to a thickness of about 0.5 μm.
m is applied.

Next, the first transparent resin substrate 31 or the second transparent resin substrate 35 having an unnecessary thickness of 0.6 mm is placed on the protective layer 83 through an adhesive layer 84 having a thickness of about 40 μm. It is bonded as a resin substrate. At this time, the reinforcing dummy resin substrate 31 or 35 has, as described above, the entire surface roughened by unevenness of about 1 to 100 μm 31c.
Alternatively, if the surface 35b (or 35c) is an adhesive surface to the transparent resin substrate 81, the two resin substrates (81, 31) or (8
1,35) can be satisfactorily adhered to each other. Of course, the center is adjusted so that the center hole 81a of the transparent resin substrate 81 and the center hole 31a or 35a of the reinforcing dummy resin substrate 31 or 35 are concentric. Thereafter, the label layer 85 is printed on the reinforcing dummy resin substrate 31 or 35.

The DVD (digital versatile disc) 80 having a single-layered signal surface is also manufactured by the above-described method using a laser beam LB from an objective lens provided in an optical pickup (not shown). By irradiating one surface 81b of 81, the signal surface formed on the other surface 81c side of the transparent resin substrate 81 can be reproduced.

A newly manufactured DVD having a single signal layer
Although the description has been made with reference to the case where the DVD 80 is formed only for reproduction by using a plurality of pit rows, the present invention is not limited to this. A groove and a land having irregularities may be formed on the surface 81c, and a recording layer may be formed on the groove and the land.

Further, in the above-described first to fourth embodiments,
Although the disc-shaped optical disk has been described, the optical recording medium according to the present invention has a substantially rectangular optical card. Of the optical card manufacturing method.

[0070]

According to the method for manufacturing an optical recording medium according to the present invention described above in detail, when an unnecessary optical recording medium such as an optical disk or an optical card is reused (crushed) without being crushed, it is newly added. The optical recording medium is manufactured by bonding the resin substrate of the optical recording medium that is no longer needed to the resin substrate of the optical recording medium to be manufactured as a reinforcing dummy resin substrate. Non-defective or returned optical recording media can be effectively reused as a reinforcing dummy resin substrate, and a bonded optical recording medium with improved adhesion strength can be obtained.

[Brief description of the drawings]

FIGS. 1A and 1B are diagrams schematically illustrating a method for manufacturing an optical recording medium according to a first embodiment of the present invention, wherein FIG. 1A illustrates a step of removing a resin substrate from an unnecessary CD. ,
(B) is a diagram showing an ultra-high-density optical disk newly manufactured by reusing an unnecessary CD resin substrate.

FIGS. 2A and 2B are diagrams schematically illustrating a method for manufacturing an optical recording medium according to a second embodiment of the present invention, wherein FIG. 2A illustrates a step of removing a resin substrate from an unnecessary CD. ,
(B) is a diagram showing a DVD having a single-layered signal surface by reusing an unnecessary CD resin substrate.

FIGS. 3A and 3B are diagrams schematically illustrating a method for manufacturing an optical recording medium according to a third embodiment of the present invention, wherein FIG. FIG. 7B is a diagram illustrating a step of taking out a substrate, and FIG. 7B is a diagram illustrating a newly manufactured DVD having a single-layered signal surface by reusing a resin substrate of a DVD having a single-layered signal surface which is no longer required.

FIGS. 4A and 4B are diagrams schematically illustrating a method of manufacturing an optical recording medium according to a fourth embodiment of the present invention, wherein FIG. FIG. 7B is a diagram illustrating a step of taking out the substrate, and FIG. 8B is a diagram illustrating a newly manufactured DVD having a single-layered signal surface by reusing a resin substrate of a DVD having an unnecessary signal surface of two layers.

FIG. 5 shows a typical optical recording medium used.
FIG. 2 is a diagram schematically showing a compact disc (CD).

FIG. 6 shows an optical recording medium generally used;
FIG. 2 is a diagram schematically showing a digital versatile disk (DVD), where (a) shows a case where the signal surface has one layer,
(B) is a diagram showing a case where the signal surface has two layers.

[Explanation of symbols]

10 compact disk (CD), 11 transparent resin substrate, reinforcing dummy resin substrate, 12 Al reflection layer, 13
Protective layer, 14: Label layer, 20: Digital versatile disk (DVD) having one signal surface 21: Transparent resin substrate, dummy resin substrate for reinforcement, 22: A
1 Reflective layer, 23 ... Protective layer, 24 ... Adhesive layer, 25 ... Dummy resin substrate, reinforcing dummy resin substrate, 26 ... Label layer, 30 ... Digital versatile disk (DVD) having two signal surfaces 31 ... First Transparent resin substrate, dummy resin substrate for reinforcement, 32
... Au transflective layer, 33 ... Transparent adhesive layer, 34 ... Al
Reflective layer, 35: second transparent resin substrate, reinforcing dummy resin substrate, 36: label layer, 50: ultra-high-density optical disk of the first embodiment, 51: curable resin layer for signal surface, 52: A
l reflective layer, 53: transparent adhesive layer, 54: transparent film,
60 DV of the second embodiment having a newly manufactured signal surface of one layer
D, 61: Transparent resin layer, 62: Al reflective layer, 63: Protective layer, 64: Adhesive layer, 65: Label layer, 70: DVD with a single signal surface of the third embodiment, 71: Transparent resin layer, 72 ... Al reflective layer, 73 ... Protective layer, 74 ... Adhesive layer, 75 ... Label layer, 80 ... DVD with one signal surface newly manufactured in the fourth embodiment, 81 ... Transparent resin layer, 82 ...
Al reflective layer, 83: protective layer, 84: adhesive layer, 85: label layer.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F301 BF01 BF31 5D029 KB11 RA07 RA50 5D121 AA02 FF03 FF11 FF13 GG02 GG21 GG22

Claims (1)

[Claims] When reusing (recycling) an optical recording medium such as an optical disk or an optical card that is no longer needed without grinding, a resin substrate of a newly manufactured optical recording medium is used.
A method of manufacturing an optical recording medium, comprising: bonding an unnecessary resin substrate of an optical recording medium as a reinforcing dummy resin substrate to manufacture an optical recording medium.