JPH03108140A - Method and apparatus for continuous production of substrate for optical recording medium - Google Patents

Abstract

PURPOSE:To prevent the intrusion of bubbles into a UV curing resin and to continuous produce the substrate with good productivity by using the rugged patterns of a rolled stamper which is plastically deformable and transferring the patterns onto the substrate. CONSTITUTION:The rugged patterns of the stamper 3 are transferred onto the sheet substrate 1 by using the rolled stamper 3 which is plastically deformable. The intrusion of the bubbles into the UV curing resin 9 is then prevented and the follow-up of the stamper 3 and the substrate 1 is improved. An error rate is thus improved. The accuracy of the ruggedness corresponding to the required guide grooves and information of the stamper 3 is obtd. The optical recording substrate is continuously produced with the good accuracy in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for continuously manufacturing a substrate for an optical recording medium suitable for optical writing and recording using a laser or the like.

[Conventional Technique #I] Conventionally, optical information recording media such as optical disks or optical cards have optically detectable minute pits in the form of tracks on a thin recording layer provided on a substrate. By forming this, information can be recorded with high density. In such optical information recording media, it is necessary to scan a laser beam along a track when recording and reproducing information, and therefore a substrate with a guide groove for tracking is generally used.

A method for manufacturing such guide grooves or substrates with guide grooves is compression molding, in which a softened plastic material is pressed with a stamper and then solidified.
On Mol d) method, injection molding (
injection mold) method and ultraviolet curing resin (
Transfer the guide groove from the stamper using a Photo Polymer (Photo Polymer).
Among the known methods, method 22 is the best in terms of transferability of guide grooves and solvent resistance of the substrate. The fact that the substrate has excellent solvent resistance is particularly advantageous when an organic material is used as the recording material and a recording layer is formed by coating.

In this case, since it is possible to use a solvent that cannot be used because it corrodes the substrate, it is possible to greatly expand the range of choices of recording materials.

Furthermore, the 22 method has the great advantage of requiring very little capital investment compared to other methods.

However, the 22 method has a problem in that it takes longer to manufacture per substrate than other methods, making it unsuitable for mass production. Therefore, as disclosed in, for example, WO 381 Oko 311 (Japanese Patent Application No. 62-506504), a stamper on which an uneven pattern is formed is used to transfer and form the uneven pattern of this stamper onto a film base material. has proposed a technique for continuously manufacturing film-like substrates for optical information recording media. Specifically, for example, after applying an ultraviolet curable resin to a rolled stamper on which a concavo-convex pattern is formed, it is overlapped with a film base material provided with an anchor material layer as needed, and then irradiated with ultraviolet rays to cure the ultraviolet curable resin. A technique has been proposed in which the resin is cured, and then the film substrate and the cured ultraviolet curable resin are peeled off using a stamper.

[5P, the problem that Ming is trying to solve] However, when superimposing the ultraviolet curable resin and the base material using the above method, the contact between the resin coated surface and the base material is between the liquid surface and the solid surface, and the contact There was a problem that air bubbles were easily mixed in.

Furthermore, although submicron precision is required for the guide grooves of the roll-shaped stamper and the unevenness corresponding to the information, it is necessary to eliminate rotation irregularities of the DC motor that drives the roll-shaped stamper and rotation irregularities caused by gears with even higher precision. It wasn't very easy. This means that the eccentricity of the recording medium
This was one of the causes of defects and recording errors.

The present invention has been made in view of the above problems, and by using a roll-shaped stamper that is elastically deformed as a roll-shaped stamper, it is possible to prevent air bubbles from being mixed into the ultraviolet curable resin, and to improve the ability of the roll-shaped stamper and sheet. It is an object of the present invention to provide a method and apparatus for continuously manufacturing a substrate for an optical recording medium with good productivity, which improves the error rate by improving the tracking of the substrate.

[Means for Solving the Problems] That is, the present invention uses a rolled stamper having a fine uneven pattern corresponding to guide grooves and/or information,
In a method for continuously manufacturing a substrate for an optical recording medium by transferring and forming an uneven pattern of the stamper onto a sheet substrate using an ultraviolet curing resin, the unevenness of the stamper is formed using an elastically deformable roll-shaped stamper. This is a method for continuously manufacturing a substrate for an optical recording medium, characterized by transferring a pattern onto a sheet substrate.

Further, the present invention uses a rolled stamper having a fine uneven pattern corresponding to guide grooves and/or information,
In an apparatus for continuously manufacturing substrates for optical recording media by transferring and forming a concavo-convex pattern of the stamper onto a sheet substrate using an ultraviolet curing resin, the roll-shaped stamper is composed of a roll-shaped stamper that is elastically deformed. 1 is a continuous manufacturing apparatus for optical recording medium substrates, characterized in that:

The present invention will be explained in detail below.

The present invention improves the contact between the sheet substrate and the roll stamper by using an elastically deformable roll stamper as the roll stamper, and prevents the mixing of air bubbles into the ultraviolet curable resin sandwiched between the sheet substrate and the roll stamper. This makes it easier to prevent. Furthermore, the sheet substrate has excellent followability against fine rotational irregularities of the roll-shaped stamper and electric current, thereby easily reducing medium errors.

FIG. 1 is a structural diagram showing an example of an apparatus used in the continuous manufacturing method of optical recording medium substrates of the present invention. In FIG. 1, a sheet substrate 1 is configured to be fed out by a feeding roller 2. As shown in FIG. The sheet substrate 1 is not limited in any way as long as it is flexible, and for example, plastic sheets such as polycarbonate, acrylic resin, polyolefin resin, polyester resin, and epoxy resin can be suitably used. In addition.

A primer layer may be formed on the surface of the sheet substrate 1 in order to improve the adhesion with the ultraviolet curing resin 5.

On the surface of the rolled stamper 3, guide grooves 6 and unevenness according to information are formed, and the sheet substrate l sent out from the feeding roller 2 is conveyed along the circumference of the rolled stamper 3. The diameter of the rolled stamper 3 varies depending on the thickness and material of the sheet substrate l, but for example, considering an optical disc using 1.2 mm thick polycarbonate, the diameter is φ3.
00m5 or more is preferable. In addition, even considering an optical card made of polycarbonate with a thickness of 150 mm or more, it is preferable.

As shown in FIG. 1, such a roll-shaped stamper 3 is made by providing an elastomer 5 such as polyurethane, natural rubber, isoprene rubber, chloroprene rubber, silicone rubber, etc. on the outer peripheral surface of a metal core 4, and forming an elastic roll. Ni is formed on the outer peripheral surface of the elastic roll with a thickness of 0.1 to 0.3 mm.
A method of bonding the flat plate stamper 6 along the roll surface with an adhesive or the like.

Alternatively, it can be manufactured by mechanically fixing with screws or the like.

Figure t52 is a structural diagram showing another apparatus used in the continuous manufacturing method of optical recording medium substrates of the present invention. In FIG. 2, the roll-shaped stamper 3 has a stamper 7 made of an elastic resin such as silicone resin or fluororesin around the metal core 4, which is glued along the outer peripheral surface of the roll of the metal core 4 or directly on the roll. It can be produced by solidification molding.

The nip roller 8 has a function of pressing the sheet substrate 1 against the surface of the rolled stamper 3. A resin tank 1O containing a liquid ultraviolet curing resin 9 that is cured by ultraviolet irradiation is provided below the rolled stamper 3. In the resin tank IO, a liquid ultraviolet curing resin 9 is applied to the surface of the roll stamper 3 by a coating roller 11 that rotates while being pressed against the surface of the roll stamper 3. The resin liquid applied in this way is BLATE! After the thickness is adjusted to be uniform by step 2, the nip roller 8 fills the space between the sheet substrate 1 and the rolled stamper 3. The thickness of the coating is 0.1. - Adjust so that no bubbles are mixed in between 50 and 50 cm.

As the ultraviolet curable resin 9, a prepolymer, oligomer, hexamer, etc. having an unsaturated bond in the molecule can be used. For example, unsaturated polyesters, acrylates such as epoxy acrylate, urethane acrylate, and polyether acrylate, and one or more types of methacrylates such as epoxy methacrylate, urethane methacrylate, polyether methacrylate, and polyester methacrylate are used in the molecule. A photopolymerizable monomer having a bond, such as a mixture of functional monomers such as dicyclopentenyl acrylate, 3-butanediol acrylate, polyethylene glycol diacrylate, and pentaerythritol triacrylate, and a halogenated polymerization initiator. Radical-generating compounds such as acetophenones, benzophenone, benzoin, benzoin ether, Michler's ketone, benzyl, benzyl dimethyl ketal, tetramethylthiuram monosulfide, and thioxanthone are used, and they are easy to peel off from the stamper in the cured state and are easy to bond with the recording layer. Any material with good matching may be used; however, the application of the liquid ultraviolet curing resin 9 to the rolled stamper 3 is not particularly limited, and a dispenser nozzle or other device may be used in place of the application roller 11 for printing. The coating method can be selected from known coating methods depending on the viscosity and coating film thickness. Further, the ultraviolet curable resin 9 may be applied directly to the sheet substrate using a coating roll 11'.

The sheet substrate l that has passed the nip roller 8 is exposed to ultraviolet rays over the entire width of the ultraviolet curing resin liquid filled between the sheet substrate l and the roll stamper 3 by an ultraviolet lamp 13 provided above the rolled stamper 3. is irradiated to cure the ultraviolet curing resin 9. The delivery roller 14 has a function of peeling off the sheet substrate 1 and the layer of the ultraviolet curable resin 9 that has been cured while being fixed thereto from the rolled stamper 3.

In this way, a concavo-convex pattern corresponding to the information on the optical disc is transferred onto the substrate, and substrates for optical information recording media can be continuously manufactured. Note that, if necessary, a step of further irradiating ultraviolet rays may be provided after the layer of ultraviolet curable resin 9 is peeled off.

In addition, the feeding speed of the sheet substrate l is preferably in the range of 0.05 to 5 m/in, preferably 0.05 to 2.5 m/in, or less than O,OS/in. The productivity cannot be increased by increasing the speed, and if the speed exceeds 5 increments/sin, air bubbles are likely to be mixed in.

[Example] Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 After forming a photoresist film (product name: AZ-1300 manufactured by Hoechst Co., Ltd.) with a thickness of 1000 on a glass master, it was exposed to light using a laser cutting device, and then developed to form a concavo-convex pattern. was formed.Next, the formed uneven pattern was sputtered on the old! After forming the J film and making the surface conductive, it is electroformed to a thickness of 0.1
- The Ni body of ■ was applied and then peeled off from the glass master disk, groove width 0.6 gm, pitch 1.6 end ■, groove depth 9
00 people 3, 5 with a spiral-shaped uneven pattern
A Ni flat plate stamper for an inch optical disk was obtained.

The obtained Ni plate stamper was placed around a stainless steel core roll with an outer diameter of 350 m5+ and a width of 150 layers.
Apply epoxy adhesive (product name:
EP-170 (manufactured by Cemedine).

Twelve pieces were adhered in a row to produce a rolled stamper.

A polycarbonate sheet substrate with a thickness of 1.2 ms and a width of 130 mm was used as the substrate, and an epoxy acrylate ultraviolet curing resin (manufactured by Mitsubishi Rayon, MRA-5000) was applied to the uneven surface of the rolled stamper to a thickness of 25 mm. After supplying the stamper at a speed of 2.5 m/sin and bringing the rolled stamper and sheet substrate into close contact with nip rolls, the spread ultraviolet curing resin was exposed to ultraviolet light (a high-pressure mercury lamp, 300■W/c■2
) to cure the ultraviolet curing resin.

Next, the sheet substrate and the cured ultraviolet curable resin on it are peeled off using a roll stamper, and the sheet substrate has a concavo-convex pattern with a groove width of 0.6 mm and a pitch of 1.6 mm and a groove depth of 900 mm. I got it. No defects due to air bubbles were observed in the substrate obtained in this way, and when a disk substrate was cut from this sheet substrate with a mask using a C02 laser cutting machine and the error rate of the substrate was measured, it was found that the error rate was 10. The average value of the sheets was 5 x 10-'.

Comparative Example 1 The same operation as in Example 1 was performed except that a Ni flat plate stamper was bonded to the side surface of a stainless steel roll with an outer diameter of φ400 with epoxy adhesive as the rolled stamper. A disk substrate with a pattern was obtained. The substrates obtained in this way had some defects due to air bubbles, and the average error rate of 10 sheets was s
It was x to-'.

Example 2 A photoresist film (trade name: AZ1300, manufactured by Hoechst) having a thickness of 3000 was formed on a glass master disk, and then exposed using a laser cutting device and then developed to form a concavo-convex pattern. Next, a silicone resin (product name 2 EIO1 manufactured by Shin-Etsu Silicone) was applied to a thickness of 51 mm on the formed uneven pattern, and after curing at 60°C for 3 hours, it was peeled off from the glass master and the groove surface A silicone resin stamper for optical cards having a stripe-like concavo-convex pattern of 31!1m, pitch of 12 pitches, and groove depth of 3,000 people was produced.

This stamper was adhered to the side of a stainless steel core roll with an outer diameter of 200 mm and a width of 130 m using a silicone adhesive (product name: KE41, manufactured by Shin-Etsu Silicone) in rows of 10 stampers to produce a rolled stamper. .

A polycarbonate sheet substrate with a thickness of 0.4 mm and a width of 120 m5 was used as the substrate, and the sheet substrate was moved at a speed of 3 / s.
In, the same operation as in Example 1 was performed to make the groove width 3.
A substrate for an optical card was obtained which had a concavo-convex pattern with a pitch of 12 μm and a groove depth of 3000 mm. No defects due to air bubbles were observed in the substrate thus obtained, and the average error rate of one card substrate was 7×10'''.

[Effects of the Invention] As explained above, according to the present invention, by using a roll-shaped stamper that is elastically deformable as a roll-shaped stamper, it is possible to prevent air bubbles from being mixed into the ultraviolet curable resin, and to make the roll-shaped stamper It is possible to continuously manufacture a substrate for an optical recording medium with good productivity and improved error rate due to good tracking of the sheet substrate.

[Brief explanation of drawings]

FIG. 1 is a structural diagram showing an example of the apparatus used in the continuous manufacturing method of optical recording medium substrates of the present invention, and FIG. F52 is a structural diagram showing another example of the apparatus of the present invention. l... Sheet substrate 2... Feeding roller 3.
...Rolled stamper 4...Metallic core 5...Elastomer 6...Ni stamper 7...Elastic resin stamper 8...Nip roller

Claims (4)

[Claims] (1) A roll-shaped stamper having a fine uneven pattern corresponding to guide grooves and/or information is used, and the uneven pattern of the stamper is transferred onto a sheet substrate using an ultraviolet curing resin to form an optical recording medium. 1. A method for continuously manufacturing a substrate for an optical recording medium, the method comprising using an elastically deformable roll stamper to transfer a concavo-convex pattern of the stamper onto a sheet substrate. (2) A roll-shaped stamper having a fine uneven pattern corresponding to guide grooves and/or information is used, and the uneven pattern of the stamper is transferred onto a sheet substrate using an ultraviolet curing resin to form an optical recording medium. 1. An apparatus for continuously manufacturing substrates for optical recording media, characterized in that the roll-shaped stamper is comprised of a roll-shaped stamper that is elastically deformed. (3) The continuous manufacturing apparatus for optical recording medium substrates according to claim 2, wherein the elastically deformable roll-shaped stamper is formed by forming a metal stamper on an elastic roll. (4) The continuous manufacturing apparatus for optical recording medium substrates according to claim 2, wherein the elastically deformable roll-shaped stamper is formed by forming a resin stamper on a metal roll.