JPH11238262A - Manufacture of optical disk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the requirement for the direct printing process on a disk substrate and to conduct a label printing for a both-surface reading/writing type disk by pasting two disk substrates together using a pressure sensitive adhesive sheet on which picture are beforehand designed. SOLUTION: A DVD-R disk substrate 11, which has a recording layer on one side, and a transparent disk substrate 12 are pasted together on a pressure sensitive adhesive sheet 41-1, on which pictures are beforehand designed. In order to provide the pictures on the sheet 41-1, adhesives are colored by pigments and dyes, for example, or colored adhesives are used. For the case of the DVD-RAM, which has recording layers on both surfaces, the film, which has the thickness that is equal to the thickness of the adhesive layer having a picture design beforehand, is sandwitched at the portion corresponding to the inner periphery of the recording layers and other portion is pasted by the sheet made of adhesive. Thus, the production cost is reduced, no obstruction is made for the clamping of a drive and a user easily recognizes the kind of an optical disk and its contents.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing an optical disk having a bonding structure.

[0002]

2. Description of the Related Art An optical disk can record a huge amount of data.
Since the record can be easily read, it is used everywhere as a means for recording and transmitting information. For this optical disc, after the duplication process and the process of applying the recording film have been completed, the spacer is inserted into the disc substrate after measuring the reflectivity and measuring the defect, and the two disc substrates are bonded together, or the adhesive is attached to the back surface. It is manufactured by applying and sticking together.
FIG. 1 shows a basic configuration of an optical disk.
Is a clamping area, and 14 is a recording area.

[0003] By the way, an optical disk which does not enter a cartridge or the like but directly touches a user (for example, C
D, CD-ROM, DVD, etc.) are generally printed (label printed) on the back side of the recording surface so that the contents of the optical disk can be seen by the user. Conventionally, as shown in FIG. 4, printing is performed on the inner surface of a disk substrate 12 having no recording layer, and the disk substrate 11 having the recording layer is bonded to the disk substrate 11 with an adhesive sheet. In FIG. 4, 21 is a recording groove, 22 is a recording material, and 41 is an adhesive layer (adhesive sheet).

[0004]

According to the conventional method of manufacturing an optical disk employing the bonding method, if the optical disk as shown in FIG. 4 does not have a recording layer on one disk substrate, this recording layer Label printing is performed on the inner surface of the disk substrate having no recording layer, and this is bonded to the disk substrate having the recording layer. Therefore, two steps of label printing on the disk substrate 12 and formation of an adhesive layer on the printed surface are required. Becomes In the case of an optical disc in which both disc substrates have a recording layer, the printing area is limited to the area of the clamping area, and the clamping area is the area used for clamping the drive (player). But printing here is quite difficult.

An object of the present invention is to design an optical disk label, an optical disk grade, a brand, and the like on a member for bonding two disk substrates in advance, thereby making it difficult to perform a direct printing process on a disk substrate. It is intended to reduce costs and reduce costs, and to enable label printing of a double-sided reading (writing) type optical disk.

[0006]

According to the present invention, first, in a method of manufacturing an optical disk constituted by bonding two disk substrates, an adhesive sheet in which a pattern or the like is designed in advance is provided. And a method for manufacturing an optical disk, characterized by performing the method using

Secondly, in a method of manufacturing an optical disk constituted by laminating two disk substrates, the lamination is performed in advance by using an adhesive layer portion and a film-like design having a design substantially the same thickness as the adhesive layer. The present invention provides a method for manufacturing an optical disk, wherein the method is performed using a pressure-sensitive adhesive sheet comprising:

Third, in the first or second optical disk manufacturing method, one of the two disk substrates has a recording layer, and the other disk substrate is made of a transparent member. There is provided a method of manufacturing an optical disk, which comprises bonding two disk substrates so that a design or the like designed from the side can be seen.

Fourthly, in the above-mentioned first or second method for producing an optical disk, both the substrates of the two disks have a recording layer, and these are laminated with an adhesive sheet provided with a design portion in a portion other than the recording area. The present invention also provides a method for manufacturing an optical disk, characterized in that a design or the like is visible in an inner diameter part clamping area inside a recording layer.

According to the optical disk manufacturing method of the present invention, the two disk substrates are bonded to each other with the adhesive sheet on which necessary items and other patterns are printed, so that troublesome printing on the disk substrate is omitted.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The optical disc targeted by the method of the present invention is DVD
It is constituted by bonding two disk substrates as described above. Optical discs constructed by bonding two disc substrates in this way include a type having a recording layer only on one side and a type having a recording layer on both sides.

According to the method of the present invention, when a sheet-like adhesive is used for bonding two disk substrates, the adhesive sheet itself is designed with a design or the like, and is bonded to each other. This has the effect (FIG. 2). As the pressure-sensitive adhesive sheet, there is a pressure-sensitive adhesive sheet using an acrylic pressure-sensitive adhesive. For example, a pressure-sensitive adhesive sheet manufactured by Nitto Denko Corporation is used for laminating disk substrates. In order to provide a design or the like on the pressure-sensitive adhesive sheet, for example, a method of coloring the pressure-sensitive adhesive with a pigment or a dye, a method of using a colored material for the pressure-sensitive adhesive itself, or the like can be considered.

Further, as a method of putting a design or the like into the adhesive sheet, there is a method in which an adhesive layer and a film-shaped material having a thickness substantially equal to the thickness of the adhesive layer are bonded.
The thickness of the adhesive layer for DVD is 40 to 50 μm, and is combined with a film having a similar thickness. Since the bonding is performed on the entire surface of the disk substrate, a sufficient adhesive force (even if it does not necessarily have to have an adhesive function) composed of an adhesive part necessary for the bonding and a designed film part (this part does not necessarily have to have an adhesive function). Adhesion) is obtained (FIG. 3). FIG.
In the figure, 41 is an adhesive layer (adhesive sheet), and 42 is a designed film-like portion.

The "design of a design or the like" referred to in the present invention includes characters and symbols indicating the type, contents, grade, etc. of the optical disk in addition to the design. With the above configuration, for example, when the disk substrate 11 having a recording layer on one side and the transparent disk substrate 12 obtained by injection molding or the like are bonded together, the bonding as shown in FIG. 2 is performed. A design or the like can be seen through the transparent disk substrate 12 side. Further, in the case of laminating a disk substrate having a recording layer on both sides, the printing place becomes very narrow as shown in FIG. 1, but in the structure of the present invention, the pattern is formed on the adhesive layer corresponding to the clamping area. For example, by inserting a designed adhesive film in a portion corresponding to a clamping area, it is possible to insert a design into an optical disc without obstructing clamping of a drive (player).

[0015]

Next, the present invention will be described more specifically with reference to examples.

Example 1 A DVD-R having a recording layer on one side (a write-once disk, R is an abbreviation for Recordable) and a transparent disk substrate were bonded together with an adhesive sheet whose design was designed in advance. The type of DVD-R to be added by the user can be mass-produced in a fixed design such as a recordable time (capacity) and a brand. Therefore, a DVD-ROM (or DVD) whose design must be changed depending on the contents (contents) -Video) and the like. DVD with recording layers on both sides
-RAM (disk that can be repeatedly written and erased)
Area on the inner circumference of the recording layer (clamping area)
With a film designed in advance, etc.
The other parts were bonded with a sheet composed of an adhesive. The two disk substrates are located on the inner circumference (clamping
The adhesive strength (adhesive strength) is sufficient because they are stuck together except for (area). The designed film has the same thickness as the adhesive layer and is made so that the capacity and brand can be read from both sides (front and back). Therefore, whichever type of disk is used, the type of the disk is obvious, and the disk A and the disk B
The face (back, front) can also be identified.

[0017]

According to the first aspect of the present invention, the printing step on the disk substrate can be omitted, and the cost reduction effect is large. According to the second aspect of the present invention, a more clearly designed optical disk can be obtained. According to the invention of claim 3,
The type of optical disk, even without the printing process on the disk substrate,
It can provide a disc whose contents can be understood by the user. According to the fourth aspect of the present invention, it is possible to provide an optical disk that allows the user to know the type and contents of the optical disk without disturbing the clamp of the drive even with an optical disk having a double-sided recording layer.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of an optical disc.

FIG. 2 (a) is a diagram showing a state in which two substrates are bonded with a designed pressure-sensitive adhesive sheet, and FIG. 2 (b).
Is a top view of a state where these are bonded together.

FIG. 3 is a top view of a state in which two substrates are bonded together with a film designed only for a clamp.

FIG. 4A is a view showing a state where two disk substrates are placed facing each other for bonding, and FIG. 4B is a view showing a state where they are bonded together.

[Explanation of symbols]

 11 Disk substrate (recording layer side) 12 Disk substrate (no recording layer side) 13 Clamping area 14 Recording area 21 Recording groove 22 Recording material 31 Printing section 41 Adhesive layer (adhesive sheet) 41-1 Designed adhesive sheet 42 Designed film part

Claims (4)

[Claims] 1. A method for manufacturing an optical disk, comprising: bonding two disk substrates, wherein the bonding is performed using an adhesive sheet on which a design or the like is designed in advance. 2. A method of manufacturing an optical disk comprising two disk substrates bonded to each other, wherein said bonding is performed in advance with an adhesive layer portion and a film-shaped portion on which a design or the like having substantially the same thickness as the adhesive layer is designed. A method for producing an optical disk, wherein the method is performed using an adhesive sheet comprising: 3. One of the two disk substrates has a recording layer, and the other disk substrate is made of a transparent member, and the two disk substrates are designed so that a design or the like can be seen from the transparent member side. 3. The method for manufacturing an optical disk according to claim 1, wherein a disk substrate is bonded. 4. The two disk substrates both have a recording layer,
2. The method according to claim 1, wherein the adhesive layer is attached to a portion other than the recording area with an adhesive sheet provided with a design portion so that a design or the like can be seen in an inner diameter portion inside the recording layer.
Or the method of manufacturing an optical disc according to 2.