JPS63269347A - Production of optical recording medium - Google Patents

Abstract

PURPOSE:To prevent intrusion of air bubbles into a 2P cured resin by carrying out an operation of packing a photopolymer between a stamper and transparent substrate in an inert gaseous atmosphere in a substrate molding method (2P method) of transferring a preformat part and pregroove part by using the photopolymer. CONSTITUTION:A replica is constituted of the glass substrate 1, a silane coupling agent layer 2 and the pregroove part 3 formed by the 2P method. A flat substrate 5 is a glass substrate subjected to a surface treatment and a dispensing nozzle 6 drops a 2P liquid onto the nickel stamper 4. A substrate supporting arm 7 removes the support of the flat substrate 5 after the 2P liquid is dropped. The entire part of a supporting base 8 connected to a motor in a lower part is rotated. The inside of the device is so constructed as to allow gas flow so that the inert gaseous atmosphere of argon, etc., can be formed. The intrusion of the air bubbles into the 2P cured resin is thereby prevented, the presence of the unreacted monomer is decreased and the oxidation resistance of the optical recording medium is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing an optical recording medium in which information is written and read using laser light.

[Conventional technology]

JOlJRNAL OF RADIATIONCU
In RING JANUARY 1084, A, J,
M., VAN DEN IIROEK et al. describe a conventional substrate molding method (2P method) using 7 otobolimer. In the atmosphere, photopolymer is applied on the stanbar, the circular base μ is uniformly curved in the radial direction, and UV curing #! #This is a method in which resin is placed in contact with the sushi and filled between the stand bar and the substrate to prevent air bubbles from entering. or,
AUDIO ENGINEERING 5oCIETY
1084 0CTOnER8-11NEW YO
Matsushita Electric Industrial Co., Ltd. has announced this in Rl.
This is a method of filling the gap between the stand bar and the substrate.

(Problem to be solved by the invention) In the conventional technology, ultraviolet curing resin (2P liquid) is filled between the standber and the substrate in the atmosphere.
It was impossible to completely prevent air bubbles from entering the P liquid. Moreover, the inclusion of air bubbles in the 2P liquid caused burst errors in the cured film, and the solidity of the 2P cured product on the standber caused deterioration of the stamper signal during duplication. In addition, when irradiating the 2P liquid and curing it with ultraviolet rays, it was difficult to remove the interface between the substrate and the 2P liquid, the interface between the standber and the 2P liquid, and the oxygen molecules in the liquid when filling in the atmosphere. . In the presence of oxygen molecules, the curing reaction of the 2P liquid is insufficient, and the monomers in the 2P liquid exist in an unreacted form. When fabricated, recording material (TbFeCo
, TbGdFeCo, NdDyFeCo, etc.).

Therefore, the present invention is intended to solve these problems.The purpose of the present invention is to prevent air bubbles from being mixed into the 2P liquid curing resin, and to increase the reactivity of the 2P liquid curing resin, thereby removing unreacted monomers. The objective is to reduce the presence of oxidation and improve the oxidation resistance of optical recording media.

[Means for solving problems]

The present invention uses a photopolymer to improve the unevenness of the stand bar.
That is, in a substrate molding method (2P method) in which a preformat part and a pregroove part are copied, the operation of filling a photopolymer between a standber and a transparent substrate is performed in an inert gas atmosphere. .

[Example 1] FIG. 1 shows a cross-sectional view of a replica for optical record media based on the present invention.

2 is a glass substrate, 2 is a silane cuff pulling agent layer (γ-methacryloxypropyltrimethoxysilane is used here), and 3 is a pregroove portion formed by the 2P method (the composition is TIIFA: tetrahydrofurfuryl acrylic). 80ff [n%, TMPTA:) limethylolproba/triacrylate IEiffKffi%, Irgacure 651: Ciba Geigy photopolymerization initiator dffl amount%).

FIG. 2 is a configuration diagram showing an outline of a bonding apparatus used in the present invention.

4 is a nickel stump bar, for example, pitch 1, 0.8 μm in 6 μm groove, groove depth 600 mm, thickness 0.3 mm.

5 is a flat substrate, which is a glass substrate subjected to surface treatment as described above.

6 is a dispensing nozzle that drops the 2P liquid onto the nickel stanbar.

7 is the substrate support arm, and after the 2P liquid is dropped, it is held 2)
Remove support from the board.

8 is the support stand, which is connected to the motor at the bottom and rotates the whole thing.

The inside of the device is structured to allow gas flow, and an inert gas atmosphere such as argon, nitrogen, helium, etc. can be created.

The 2P liquid is cured by irradiating it with ultraviolet light having a wavelength of 365 nm and an intensity of 50 mw/cm'' for 10 seconds.

FIG. 3 shows a cross-sectional view of the vi bamboo laminated disk produced. Here, 11 is a glass substrate, 12 is a silane coupling agent layer, 13 is a 2P repliability layer, and 14 is a protective layer (!
! 15 is Tb
The FeCo layer 16 is a 2P contact layer, and 17 is a flat glass substrate.

No bubbles were formed with the inert gas in either case.

The magneto-optical recording medium produced in the atmosphere by the conventional method and the magneto-optical recording medium produced in an inert gas atmosphere according to the present invention are placed in a constant temperature and humidity chamber at 60°C x 90% RTL, As a result of a weather resistance test, the magneto-optical recording medium according to the present invention had about twice the durability as compared to the conventional method.

[Example 2] FIG. 4 shows a sectional view of another closely bonded disk. Here, 21 is a polycarbonate substrate, 22 is a 2P repulsion layer, 23 is a protective layer (silicon nitride layer), and 24 is NdDy.
A FeCo layer, 25 a 2P adhesive layer, and 26 a flat polycarbonate substrate.

The polycarbonate substrate 21 was set in the same bonding device as in Example 1, and the groove shape of the Nirakuru stambar was adjusted to 2N).
Transfer and cure with liquid.

The inert gases used are argon, nitrogen, and F1/Off (
CF, ) was used, but no bubbles were generated in any case.

Such an optical recording medium and an optical recording medium according to a conventional method are separated at 60°.
It was placed in a constant temperature and humidity chamber of C x 90% R11, and a weather resistance test was conducted. The results are shown in FIG.

Here, 31.32 is for the conventional method, and 33.34 is for the present invention with 1λ added.

Weather resistance was checked by checking the change in n, E, R, <bit error rate) over time, and it was found that the present invention had approximately twice the durability compared to the conventional method.

In addition, in the example, Tl11? is used as the 2P repliability layer. Δ
/ TMI'TA was used as an example, but similar results were obtained with LIDIA (hexanediol diacrylate) and NPGDA (neobectyl glycol diacrylate). , Irgacula 65! is also used as a photopolymerization CI initiator. Similar results were obtained with Irgacure 907. Regarding the substrate, in addition to glass and polycarbonate, substrates having light transmittance such as epoxy and PMMAAlAPO were used to obtain the same effect as in the same invention.

Furthermore, although the case where the magneto-optical distribution L1 layer is used as an example is explained as a recording medium, it is also applicable to other optical recording media using a phase-change type or perforation dye recording layer.

〔Effect of the invention〕

As described in detail above, according to the present invention, by using a photopolymer, the uneven portions of the standber, that is, the preformat portion,
And a substrate molding method that copies the pre-groove part (2P method)
By filling the photopolymer between the standber and the transparent substrate in an inert gas atmosphere,
It was possible to prevent air bubbles from entering the 2P cured resin, and it was possible to eliminate burst errors caused by air bubbles.

Moreover, the reactivity of the 2P cured resin can be increased, and the presence of unreacted monomers can be reduced.
We were able to significantly improve the weather resistance of optical recording media.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a replica for optical record media according to the present invention. FIG. 2 is a block diagram schematically showing a bonding apparatus used in the present invention. FIG. 3 is a cross-sectional view of a closely laminated disk produced according to the present invention. FIG. 4 is a cross-sectional view of another closely laminated disk produced according to the present invention. FIG. 5 is a diagram showing the results of weather resistance tests of optical recording media based on the conventional method and the present invention. Applicant Seiko Epson Co., Ltd. 2P No. 2 Figure S

Claims (1)

[Claims] In a substrate molding method (2P method) that uses a photopolymer to copy the irregularities of a stamper, that is, the preformat part and the pregroove part, the operation of filling the space between the stamper and the transparent substrate with the photopolymer is performed in an inert gas atmosphere. 1. A method for manufacturing an optical recording medium, characterized in that the manufacturing method is carried out inside.