JPH0589535A - Method and apparatus for production of optical information recording medium - Google Patents

Abstract

PURPOSE:To provide the method for removing an optical information recording layer contg. dyes of a non-recording region and the apparatus for this method. CONSTITUTION:A recording layer dissolving liquid is discharged from a nozzle 4 to the position where the recording layer 2 on a substrate 1 ought to be removed while a disk is kept rotated, by which the recording layer of the prescribed position is removed. The position of the nozzle where the discharging of the dissolving liquid is started and stopped is set in the position apart from the radius of the disk from the center of rotation of the disk and below the disk surface.

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, and more particularly to a method and an apparatus for manufacturing an optical disc having an organic recording layer.

[0002]

2. Description of the Related Art It is a well-known technique to provide a recording layer by spinner coating in an organic dye-based optical disc. Usually, the recording media thus obtained are bonded to each other to form an air sandwich structure, but a photocurable adhesive is used as the adhesive because of its high productivity. The problem at this time depends on the dye applied to the adhesive portion.
There are 1) a decrease in adhesive strength, and 2) a deterioration in the recording material during storage due to uncured monomer accompanied by a decrease in the degree of curing of the adhesive. These improvements include (A) improvement of an adhesive having a high dye solubility, and (B) a method of wiping off a dye adhering to an adhesive portion (Japanese Patent Laid-Open No. Sho 6-62).
3-47194, JP-A-63-234429) (C) A method of washing away the dye adhering to the adhesive part with a solvent (JP-A-63-234428) and the like have been proposed, but (A) has an adhesive strength. It is difficult to achieve both good storage stability. Further, the wiping method of (B) has drawbacks such as a problem of absorbing power of the wiping material, a problem of exchanging the wiping material, and a large blurring of the boundary for removing the recording film. Further, as for (C), since the dye recording film dissolving agent is used, the dissolving agent splashes (scatters) on the disk substrate.
And the solvent pool at the tip of the solvent outflow pipe (nozzle), and due to pressure fluctuations at the start of solvent injection and solvent splattering at the nozzle tip at the end of solvent injection, the recording film in the recording area is melted. Was causing defects.

More specifically, referring to FIG. 2, for example, an optical disc having a recording layer 2 on a substrate 1 having a hole in the center is placed on a turntable 3, and the recording layer at the outer peripheral edge of the optical disc is rotated while rotating. The above problem occurs in the method of discharging the dissolution liquid of the recording layer from the nozzle 4 provided at the outer peripheral end in order to remove 2 and removing this.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to eliminate the above-mentioned drawbacks of the prior art, and to eliminate the unnecessary recording film existing on the disk adhesion surface outside the recording area, which causes a decrease in adhesion strength and storage stability. An object of the present invention is to provide a method and an apparatus for manufacturing an information recording medium, which can easily remove a recording film in a recording area without damaging it and can also remove a recording film forming liquid adhering to the back surface of a disc if necessary.

[0005]

The structure of the present invention for solving the above-mentioned problems is a manufacturing method of an optical information recording medium and an apparatus thereof as set forth in the claims.

That is, according to the present invention, in order to remove the recording layer at the outer peripheral edge outside the recording area of an optical disk in which a recording layer containing an organic dye as a main component is provided on a substrate having a central hole, the solution is dissolved in a nozzle. And a device therefor for dissolving and removing the recording layer by discharging the recording layer. Hereinafter, the present invention will be described in more detail.

As shown in FIG. 1, the dye film 3 is formed on the substrate 1.
The disc having the above is placed on the turntable 3 and the recording layer solution is discharged from the tip of the nozzle 4 while rotating the disc to remove the dye film on the outer periphery of the disc.

At this time, as shown in FIG. 1, the nozzle 4 is movable as shown by the dotted line, and is placed farther from the outer periphery of the disc and below the disc surface to discharge and stop the solution. By this, it is possible to prevent the droplets of the solution from adhering to the pigment film 3 of the disc.

That is, as shown in FIG. 1, the discharge of the solution is started at a position lower than the disk surface, and the nozzle 4 is moved upward while continuing stable discharge, and then horizontally in the direction of the disk. Then, the solution is discharged to the outer peripheral edge by moving the outer peripheral edge to an appropriate position.

When the dissolution and removal of the dye film at the outer peripheral edge is completed, the solution is continuously moved and moved horizontally to a position away from the outer peripheral edge, and further downwardly moved, and then the solution is dissolved. To stop the discharge.

At this time, as shown in FIG. 2, the angle of the nozzle with respect to the disk surface, the number of rotations of the disk, the size of the nozzle diameter, the distance between the nozzle and the disk surface, the type of the dissolving agent, and the method of injecting the dissolving agent (jetting) There are factors such as pressure). If the above factors are not properly selected, the dissolving agent will splash on the surface of the disk or will be scattered from the nozzles, and the droplets will melt the recording film in the recording area, creating a large defect.

For example, regarding the injection method, if the dissolving agent injection nozzle is fixed, the dissolving agent accumulated at the beginning of the dissolving agent injection and the tip of the nozzle at the end of the injection and the flow rate at the beginning of the dissolving agent injection ( Because the pressure is unstable, the dissolving agent may scatter in all directions at the nozzle end and reach the inside of the recording area, causing defects (even when suck back is applied, the nozzle may be agitated due to a sudden suction force). Since it will vibrate, there is a high possibility that the dissolving agent will scatter).

In the present invention, as described above, the dissolution agent injection is started and ended at a position far from the disk and below the disk surface, so that the dissolution agent injection with a very stable flow rate (pressure) can be obtained near the disk. Further, by providing the splattering prevention wall 5, it is possible to prevent the recording film from being broken by the droplets from the nozzle tip. At this time, when the dissolving agent is applied to the end surface of the disk by the movement of the nozzle, scattering of the dissolving agent occurs, which can be repelled to the outside of the disk by centrifugal force by selecting the angle of the nozzle. It is preferable that the angle of this nozzle is inclined in the direction in which the dissolving agent is sprayed toward the outer periphery of the disc as shown in FIG. 2, and even if θ = 90 °, unnecessary recording film can be removed without causing spattering, but it is preferable. The most stable result can be obtained when θ = 30 to 60 °.

The nozzle diameter φ and the distance ω between the nozzle and the disk surface are not so large factors as long as the spray pattern of the dissolving agent (FIG. 1) is implemented, but the nozzle height ω is preferably ω = 2. ~ 3 mm, nozzle diameter is the amount of lysing agent,
Depending on the type, φ <0.3mm depending on the finish of the boundary of the recording film removal (the boundary between the area with and without the recording film)
Is appropriate. The number of rotations of the disk varies somewhat depending on the jetting pressure of the dissolving agent and the type of the dissolving agent, but is generally 1500 to 20
00 rpm is preferable because the boundary finish for removing the recording film is beautiful. It is desirable to set the injection pressure to the lowest pressure at which the recording film on the rotating disk dissolves (select a solvent that dissolves even if not much pressure is applied).

By the way, when an organic dye is actually applied to the entire surface of a disk substrate by a spinner, the dye wraps around the front side of the disk substrate (the surface having no recording area) due to the low rotation of the spinner at the start of dye application. .. Therefore, when two disks are stuck together to form an air sandwich structure, the dye is attached to both surfaces and the end faces of the outer peripheral portion, which is not preferable in appearance. Therefore, it is desirable to remove the adhering dye on the back surface and the end surface of the outer peripheral portion of the disc at the same time when the unnecessary recording film outside the outer peripheral recording area is removed.

A method for solving the above problems is to use an apparatus as shown in FIG. 3 to provide a back surface adhering dye cleaning nozzle 6 in addition to the unnecessary recording film removing nozzle 4 at the outer peripheral edge spacer adhering portion. Especially. Unlike the nozzle 4, this nozzle may be of a fixed type, and factors such as the nozzle diameter injection amount may be selected appropriately. If the nozzle 6 is of a movable type, scattering will occur, so it is always a fixed type. or,
Since the dye adhering to the outer peripheral portion of the disc is removed by the solvent jet from the nozzles 4 and 6, the unnecessary recording film can be easily removed over the entire disc surface by using the apparatus shown in FIG.

In the method for manufacturing the optical information recording medium of the present invention, the dye coating, the dye removal on the outer peripheral edge portion and the dye removal on the back surface portion may be carried out by one spinner, or the respective steps may be carried out by different spinners. May be.

Further, as shown in FIGS. 1 and 3, if a splash prevention wall 6 is provided at a position closer to the center of the disk than the nozzle 4, all defects caused by the splash can be prevented.

Further, the constitution of the optical information recording medium which can be produced by the present invention will be explained.

Substrate As a necessary characteristic of the substrate, it must be transparent to the laser light used only when recording / reproducing is performed from the substrate side, and it is not necessary to be transparent when performing recording from the recording layer side. As the substrate material, for example, polyester, acrylic resin, polyamide, polycarbonate resin, polyolefin resin, phenol resin, epoxy resin, plastic such as polyimide, glass, ceramic or metal can be used.

A guide groove or guide pit for tracking and a preformat such as an address signal may be formed on the surface of the substrate.

Undercoat layer The undercoat layer has (a) improved adhesion, (b) barrier against water or gas, (c) improved storage stability of the recording layer and (d) improved reflectance, (e) ) Protection of the substrate from solvents,
(F) It is used for the purpose of forming guide grooves, guide pits, preformats, and the like. For the purpose of (a), use of various polymer materials such as ionomer resin, polyamide resin, vinyl resin, natural resin, natural polymer, silicone, liquid rubber and various silane coupling agents. For the purposes of (b) and (c), in addition to the above-mentioned polymer resin, an inorganic compound such as SiO
₂ , MgF ₂ , SiO, SiO ₂ , ZnO, TiN, Si
N or other metal or metalloid such as Zn, Cu, S, N
i, Cr, Ge, Se, Au, Ag, Al or the like can be used. For the purpose of (d), a metal such as Al, Au or the like or an organic thin film having a metallic luster such as a methine dye or a xanthene dye can be used, and the purposes of (e) and (f) For this, an ultraviolet curable resin, a thermosetting resin, a thermoplastic resin or the like can be used.

Protective Layer (Hard Coat Layer on Both Sides of Reading) The protective layer protects (a) the light reflection / absorption layer from scratches, dust, dirt and the like. It is used for the purpose of (b) improving the storage stability of the light reflection / absorption layer and (c) improving the reflectance. For these purposes, the material used for the undercoat layer can be used. Further, as inorganic materials, SiO, Si
O _{2 and the} like can also be used, and organic materials such as polymethyl acrylate, polycarbonate, epoxy resin,
Polystyrene, polyester resin, vinyl resin, cellulose, fatty acid hydrocarbon resin, aromatic hydrocarbon resin,
A heat-softening or heat-melting resin such as natural rubber, styrene-butadiene resin, chloroprene rubber, wax, alkyd resin, drying oil, or rosin can also be used.

Recording Layer The recording layer causes some kind of optical change upon irradiation with a laser beam, and information is recorded by the change, and therefore organic materials include polymethine dyes, naphthalocyanine-based materials, and
Examples thereof include phthalocyanine-based, squarylium-based, croconium-based, pyrylium-based, naphthoquinone-based, anthraquinone-based, xanthene-based, triphenylmethane-based, and metal complex compounds. The above dyes may be used alone or in combination of two or more. It's a combination, phase change, bubble,
Any of the punching type may be used. Spiropyran,
It may be a fulquid photochromic material.

The thickness of the recording layer is 100Å to 10 μm,
It is preferably 200 Å to 2 μm.

Reflective Layer If desired, a reflective layer may be provided on or under the color system layer. The reflective layer preferably has a high reflectance and is less likely to corrode, and examples thereof include a metal having gloss. Preferably A
1, Au, etc., and the film thickness is 100 Å to 50
μm, preferably 200 Å to 20 μm Examples of the film forming method include vapor deposition sputtering.

Disc Structure The recording layer obtained in the present invention may be adhered to the other substrate and adhered to the other substrate, may be an air sandwich structure, or may be a single plate structure.

The present invention will be specifically described below with reference to Examples and Comparative Examples.

[0029]

【Example】

Example 1 A dye having the following structural formula was dissolved in 2,2,2-trifluoroethanol on a polycarbonate substrate with a guide groove of φ130 mm, spin-coated to a film thickness of 900 Å, and then the method of the present invention was used. Unnecessary dyes on the outer peripheral edge and the surface were dissolved and removed.

[0030]

[Chemical 1]

Comparative Example 1 A dye layer was obtained in the same manner as in Example, and the dissolved solution was discharged at a position 3 cm far from the disc and 2 mm above the disc surface.
N and OFF were performed to remove the unnecessary dye at the outer peripheral edge (no scattering prevention wall) Comparative Example 2 A dye layer was obtained in the same manner as in Example, and the unnecessary dye at the outer peripheral edge was removed by fixing the nozzle as shown in FIG.

In each of the above Examples and Comparative Examples, 2-ethoxyethanol was used as the unnecessary dye removing liquid, and the rotation speed at that time was 1800 rpm.

Results 100 sheets of each of the examples and the comparative examples were carried out, and the results of the dispersion liquid dispersion in the recording area at that time are shown below.

[0034]

[Table 1]

[0035]

As described above, according to the present invention,
The unnecessary dye layer can be removed by a relatively small device. Further, by using the disc from which the unnecessary dye layer has been removed, it is possible to provide an optical information recording medium having an air sandwich structure with improved adhesive strength with the spacer and improved storage stability.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a specific example of the present invention.

FIG. 2 is an explanatory diagram of a conventional technique.

FIG. 3 is an explanatory diagram of another specific example of the present invention.

[Explanation of symbols]

 1 substrate 2 pigment film 3 turntable 4 and 6 nozzle 5 shatterproof wall

Claims (4)

[Claims] 1. While rotating a disk having a recording layer on a disk-shaped substrate having a central hole, the recording layer solution is discharged from a nozzle to a position where the recording layer should be removed so that the surface of the disk flows down. In a method of manufacturing an optical information recording medium in which a recording layer at a predetermined position is removed, the position of the nozzle for starting and stopping the discharge of the dissolving liquid is set so as to be farther from the rotation center of the disc than the radius of the disc and below the disc surface. A method for manufacturing an optical information recording medium, characterized in that 2. A nozzle is also arranged on the lower surface of the disc, and the recording layer dissolving liquid is discharged from the nozzle to the lower face of the disc so that the dissolving liquid flows on the rear face of the disc, and the recording layer on the front face of the disc is removed and the rear face of the disc is removed. 2. The method for manufacturing an optical information recording medium according to claim 1, wherein the recording layer forming liquid adhered to is also removed. 3. Optical information having a turntable for rotating a disc having a recording layer on a disk-shaped substrate having a central hole, and an ejection nozzle for letting a recording layer solution flow down on the surface of the disc on the turntable. An apparatus for manufacturing an optical information recording medium, characterized in that the discharge nozzle is movable from the center of the disk to a position farther than the radius of the disk and below the surface of the disk. 4. The apparatus for manufacturing an optical information recording medium according to claim 2, further comprising a scattering prevention wall adjacent to the discharge nozzle for blocking a splash of liquid flowing down from the discharge nozzle.