JPS62192947A - Method for duplicating optical disk - Google Patents

Abstract

PURPOSE:To obtain many copied disks easily from a recorded optical disk with low cost by forming a release film on a recording face of the recorded optical disk, coating an resin liquid cured by ultraviolet rays to transfer an information pattern on the recording face. CONSTITUTION:An optical disk substrate 1 having a recording layer 2 provided with pits 3 is extracted and put in a plasma reaction tank to apply gaseous growth of a tetrafluoroethylene plasma polymerization film (release film) 4 to the recording layer 2. Then an ultraviolet-ray curing resin liquid (2P liquid) having a bifunctional acrylic monomer and an optical polymerization initiator as major components is injected into a metallic die, ultraviolet rays are irradiated from the resin plate 5 while pressing the acrylic resin plate 5 to cure the packing layer thereby forming the packing layer (2P layer) 6 of acrylic resin. Then the acrylic resin plate 5 is exfoliated from the optical disc base 1 together with the packing layer 6 to form the acrylic resin plate 5 having the packing layer 6 duplicating the inverted information pattern as the recording layer 2 of the optical disk substrate 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a duplication method for manufacturing a new optical disc using a recorded optical disc on which information is engraved in the form of uneven pits as a master.

(Prior art) Conventionally, the recording film of a D RAW type optical disc has T.
e-C, Te0X and chalcogen compounds are used. The general guideline for the storage life of records is 10 years, but depending on storage conditions, the recording film may deteriorate within 10 years, or the optical disc substrate (polymethyl methacrylate) may deteriorate within 10 years.
, polycarbonate) itself may be deformed and become irrecyclable. Therefore, if a recorded optical disc can be copied at an appropriate time, the storage life of the recording can be extended as a result.

On the other hand, there is also a potential desire for users to request multiple copies of discs after recording their private information.

Conventionally, as a method to meet the above requirements, a method has been considered in which a reproduced signal is extracted from a recorded optical disc and rerecorded on a new unrecorded optical disc. However, conventional reproduction methods require several hours to reproduce one sheet, making it difficult to mass produce.
] There was a problem with respect to

(Problems to be Solved by the Invention) The present invention has been made to solve the above-mentioned problems, and provides a method for manufacturing a large number of duplicate discs from recorded optical discs easily and at low cost. That is.

[Composition of the present invention] (Means for solving the problem) The present invention forms a releasable film on the recording surface of a recorded optical disc on which information is recorded in the form of uneven pits by laser light. and a step of applying an ultraviolet curable resin liquid to transfer the information pattern on the recording surface.

The optical disc duplication method of the present invention will be explained in detail below.

First, the front wall f'l is placed on the recording surface of a recorded optical disk in which information is recorded in the form of concave and convex pitches using a laser beam.
Form the elbow. Next, a transparent 1:t(
2 [) - No. 2 [)-no. (3) At this time, it is recommended to harden the filled la layer while pressing it from the outside in order to ensure the fidelity of information transfer on the recording surface.
Funny 3. Harden the filling layer! 11 ff2, peel off transparent 2:L+IQ from each filling layer to the releasable film on the recording surface 1-3. During this peeling operation, the recording surface (-
When the releasable film is removed, a part of the recording layer is attached to the ultraviolet curable resin filling layer and peeled off.

Above) The information pattern of the recorded optical disc is transferred to the substrate side by the J culm which has been blown out. If necessary, by repeating the 1ill type processing and 2P process from the transfer body (filled @ layered M root), a transfer pattern similar to the uneven pattern of the optical disc to be copied can be obtained. A plurality of substrates having patterns can be obtained.

After forming a reflective film such as Aff or AQ on the substrate having the uneven transfer pattern obtained in this way and further applying a protective film, the final shape is formed by processing or bonding as necessary. Finalize it into an optical disc.

Methods for forming a releasable film on the recording surface of the recorded optical disc include, for example, a method of vapor phase growth of tetrafluoroethylene gas using high-frequency plasma, and a method of high-frequency sputtering using polytetrafluoroethylene as a target.

The method of vapor phase growth using high frequency plasma consists of the following process. The recorded optical disc is placed in a plasma reaction tank, and the reaction tank is degassed. Oxygen gas is introduced and the recording surface of the optical disk is cleaned and covered by plasma treatment. After degassing again, tetrafluoroethylene monomer gas (along with an inert gas as the case may be) is introduced into the reaction tank, and high-frequency plasma is applied to plasma polymerize the tetrafluoroethylene monomer. to be deposited. The thickness of this plasma polymerized film is 1000
It is preferable that it be less than Å. If the thickness is greater than this, the reproducibility of the pit shape by duplication will deteriorate. Furthermore, as a post-treatment, an inert gas may be introduced to perform a surface crosslinking treatment (Casino treatment) on the plasma membrane, or a heat treatment may be performed in a vacuum.

On the other hand, the high frequency sputtering method consists of the following process. A polytetrafluoroethylene plate is attached to the cathode (target) in the sputtering device, and a recorded optical disk is placed on the anode side. At this time, the recording surface is placed facing the target. After degassing the equipment,
An inert gas (for example, Ar, He, etc.) is introduced, and a high frequency is applied between the two electrodes. As a result, polymerizable active species are ejected from the polytetrafluoroethylene target, forming a polymer film and depositing -C on the recording surface of the optical disc. The thickness of this polymer film was also reduced to less than 1000 Å as described above.
It is preferable that

The ultraviolet curable resin liquid (2[) liquid) is a liquid resin that is polymerized and cured by ultraviolet rays, and acrylic resin is generally used. The components contained in (a) include -functional meth)acrylic monomers, trifunctional (meth)acrylic monomers, trifunctional (meth)acrylic monomers, or polyfunctional (meth)acrylic monomers having more (meth)acrylic functional groups. It mainly contains a photopolymerization initiator together with a reactive prepolymer, and additives such as a fine antistatic agent and a polymerization inhibitor may be added as appropriate.

Examples of the transparent substrate include an acrylic resin plate, a glass plate, and the like.

(Embodiments of the Invention) Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 5.

Example First, a recorded optical disc with a hollow structure (recording layer: T e
-C), and the optical disk substrate 1 having the recording layer 2 provided with pits 3 as shown in FIG. 1 was taken out.

Next, the optical disk substrate 1 was placed in a plasma reaction tank (not shown), and the reaction tank was degassed to 10-' torr. Subsequently, high-frequency plasma is applied while supplying a mixed gas of He and 02, cleaning is performed, and then degassing is performed again. After the inside of the reaction tank reached a vacuum level of 10-7 torr, a 1:1 mixed gas of N2 and tetrafluoroethylene was introduced at a flow rate of 150 cc/min, and the pressure inside the reaction tank was reduced to 0.
．． A high frequency plasma of 250 W is applied while keeping the pressure constant at 15 tOrr, and as shown in FIG. (H1 type r9) 4 was grown in vapor phase. After that, a casi+1g treatment or a vacuum heat treatment was performed as necessary.

Next, the optical disk substrate 1 on which the release film 4 was formed was placed in a mold (not shown) so that the surface of the recording layer 2 was positioned slightly below the opening surface of the mold, and then An acrylic resin plate 5 was installed on the upper surface of the opening of the mold, and was placed with a slight gap from the mold release film 4 of the optical device substrate 1. Subsequently, an ultraviolet curable resin liquid (2P liquid) containing a trifunctional acrylic monomer and a photopolymerization initiator as main components is injected into the mold, and the releasable film 4 of the optical disk substrate 1 and the acrylic resin plate 5 are injected into the mold. After filling the space between the acrylic resin plate 5 and the acrylic resin plate 5, ultraviolet rays were irradiated from the resin plate 5 side while pressing the acrylic resin plate 5 to harden the filling layer, thereby forming an acrylic resin-based filling layer (2P layer) 6 (third (Illustrated)

Next, the acrylic resin plate 5 is peeled off from the optical disk substrate 1 together with the filling layer 6 to produce the acrylic resin plate 5 on which the filling layer 6 to which the information pattern opposite to that of the recording layer 2 of the optical disk substrate 1 is transferred is attached. (Illustrated in Figure 4). At this time, since the releasable film 4 formed on the surface of the recording layer 2 of the optical disk substrate 1 has extremely excellent releasability, there was no problem that part of the filling layer 6 would chip or fall off. . Further, by forming a releasable film and repeating the above-described process from one recorded optical disc, an acrylic resin plate having a filling layer on which an information pattern is transferred can be obtained any number of times.

Next, on the filling layer (2P layer) 6 of the acrylic resin plate 5, a reflective film 7 made of approximately 1000 layers of Ag was formed, and a protective film 8 made of ultraviolet curable resin was further formed with a thickness of 5 μm ( (Illustrated in Figure 5). After this, it is processed into a disk shape,
It was assembled into a hollow optical disc using spacers.

When a playback test was performed on the obtained optical disc, the error rate was almost the same as that of the recorded optical disc as a master disc. On the other hand, the information pattern of the optical disc was applied to the filling layer (2P layer) of the acrylic resin plate by the same method as the above example except that the plasma polymerized film (llllll type film) was not formed on the recording surface of the recorded optical disc. When the information was transferred, the adhesion between the recording layer of the optical disc and the 2P layer was so strong that the information pattern of the recording layer could not be transferred to the 2P layer.

[Effects of the Invention] As detailed above, according to the optical disc duplication method of the present invention, a large number of duplication discs can be manufactured easily and at low cost from recorded optical discs, and the lifespan of the optical disc can be extended by one. It has remarkable effects, such as being able to extend the number of optical disks to a maximum of 10,000 yen, and providing replica (copying) services for recorded optical discs.

[Brief explanation of drawings]

FIGS. 1 to 5 are cross-sectional views showing a method for duplicating an optical disk in an embodiment of the present invention in the order of steps. DESCRIPTION OF SYMBOLS 1... Optical disk substrate, 2... Recording layer, 3... Recorded pits, 4... Plasma polymerized film (mold release film)
, 5... Acrylic resin plate, 6... Filled layer (2P layer)
, 7... Reflective film, 8... Protective film. Applicant's representative Patent attorney Takehiko Suzue No. 1! - 2nd [;ko1ζ[shi3 [:2i4Fig.

Claims (3)

[Claims] (1) A process of forming a releasable film on the recording surface of a recorded optical disc on which information has been recorded in the form of uneven pits using a laser beam, and applying an ultraviolet curable resin liquid to provide information on the recording surface. 1. A method for duplicating an optical disc, comprising the step of transferring a pattern. (2) A method for duplicating an optical disk according to claim 1, wherein the releasable film is formed by vapor phase growth of tetrafluoroethylene monomer gas using high-frequency plasma. . (3) The method for duplicating an optical disk according to claim 1, wherein the releasable film is formed by high-frequency sputtering of polytetrafluoroethylene.