JP2007141340A - Optical information recording medium, substrate for optical information recording medium, stamper, optical information recording medium manufacturing method and stamper manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stably perform information recording to a record layer by surely detecting groove meandering parts even in an optical disk having a substrate in which record layers and grooves are formed in this order seen from a direction where laser beams are emitted. <P>SOLUTION: A pregroove 16 has a plurality of meandering parts 40 in the optical disk having the substrate in which the recording layers and pregrooves 16 are formed in this order seen from the direction where laser beams for recording and/or reproduction are emitted. A meandering part 40 has a first bent part 44 that is bent toward a first groove 42a adjacent to one side of a corresponding land 36 and a second bent part 46 that is bent toward the land 36 from a second groove 42b adjacent to the other of the land 36, and satisfies 100 nm<T1<200 nm when the amount of projection to the first groove 42a of the first bend part 44 is set to T1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat mode type optical information recording medium capable of writing (recording) and reading (reproducing) information using a laser beam having a high energy density, a substrate for an optical information recording medium, a stamper, and an optical information recording medium And a stamper manufacturing method.

  Conventionally, an optical information recording medium (optical disc) capable of recording information by laser light is known. Such optical disks include those having one information recording layer and those having two information recording layers.

  A first optical disc having one information recording layer includes a substrate having a pregroove formed on the surface, a reflective layer formed along the surface of the substrate, an information recording layer formed on the reflective layer, And a protective layer formed on the information recording layer.

  A second optical disc having two information recording layers includes a substrate having a first pregroove formed on a surface thereof, a translucent reflective layer formed along irregularities on the surface of the substrate, and the translucent reflective layer. A first information recording layer formed on the first information recording layer, an intermediate layer formed on the first information recording layer and having irregularities formed on the surface, and a second layer formed along the irregularities on the surface of the intermediate layer. It has an information recording layer, a reflective layer formed on the second information recording layer, and a protective layer formed on the reflective layer (see, for example, Patent Documents 1 to 3). The reflective layer is formed along the unevenness of the intermediate layer, whereby the unevenness of the reflective layer functions as the second pregroove of the second information recording layer.

  In addition to the formation of address pits for address detection, the pre-groove of the first optical disc and the first pre-groove and the second pre-groove of the second optical disc described above, the servo control of the spindle motor, the tracking control of the pickup, Servo pre-pits for focus control are formed.

  In addition, there is an example in which the pregroove of the first optical disc or the first pregroove and the second pregroove of the second optical disc are wobbled (see, for example, Patent Document 4). By wobbling, sector management information such as sector addresses can be given, and rotation control information at the time of recording can be obtained by reproducing the wobbled pregroove, so dedicated address pits and servo prepits can be obtained. It is unnecessary to provide the data pits, and the data writing efficiency can be improved by the amount of these address pits and servo pre-pits. In addition, there is an advantage that a method effective at the time of continuous data writing such as CLV rotation control can be adopted.

Japanese Patent Laid-Open No. 2005-4808 Japanese Patent Laid-Open No. 10-283682 JP-A-8-203125 Japanese Patent Laid-Open No. 9-219024

  By the way, when information is recorded on the information recording layer of the first optical disc, laser light is irradiated in the direction from the end face of the substrate toward the information recording layer, and the laser light is imaged on the information recording layer to record information. To do.

  In addition, when recording information on the first information recording layer of the second optical disc, laser light is irradiated in a direction from the end surface of the substrate toward the first information recording layer, and the laser light is coupled to the first information recording layer. Image and record information. Similarly, when recording information on the second information recording layer, laser light is irradiated in a direction from the end face of the substrate toward the second information recording layer, and the laser light is imaged on the second information recording layer. Record information.

  When recording information on the information recording layer of the first optical disc or the first information recording layer of the second optical disc, the pregroove and the information recording layer (first information recording) are arranged in this order as viewed from the direction of laser light irradiation. Since it is formed, when the pre-groove or the first pre-groove is wobbled, the wobbling shape can be reliably detected with the reproduction laser beam. Similarly, even when address prepits or servo prepits are formed in the pregroove or the first pregroove, these prepits can be reliably detected by the reproduction laser beam.

  However, in recording information on the second information recording layer of the second optical disc, the second information recording layer and the second pregroove are formed in this order when viewed from the direction of laser light irradiation. For this reason, when the second pregroove is wobbled, the wobbling shape is partially hidden by the pits recorded in the second information recording layer and cannot be reliably detected by the reproduction laser beam. Arise. Similarly, even when address prepits or servo prepits are formed in the pregroove or the first pregroove, these prepits are hidden by the pits recorded in the second information recording layer. This causes a problem that it cannot be reliably detected.

  The present invention has been made in view of the above problems, and its object is to provide a substrate on which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam. It is an object of the present invention to provide an optical information recording medium that can reliably detect a meandering portion of a groove and can stably record information on a recording layer.

  Another object of the present invention is to provide an optical information recording medium capable of reliably detecting the meandering portion of the groove and easily realizing an optical information recording medium capable of stably recording information on the recording layer. It is to provide a substrate for a recording medium.

  Another object of the present invention is to provide a stamper capable of reliably detecting a meandering portion of a groove and easily producing an optical information recording medium capable of stably recording information on a recording layer. It is to provide.

  Another object of the present invention is to provide an optical information recording medium capable of reliably detecting the meandering portion of the groove and easily producing an optical information recording medium capable of stably recording information on the recording layer. It is an object of the present invention to provide a recording medium manufacturing method and a stamper manufacturing method.

An optical information recording medium according to a first aspect of the present invention is an optical information recording medium having a substrate on which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam. The groove has a plurality of meandering portions, and the meandering portion includes a first curved portion that curves toward the first groove adjacent to one of the lands, and a second groove adjacent to the other of the lands. A second bending portion that curves toward the first projection, and when the protruding amount of the first bending portion with respect to the first groove is T1,
100 nm <T1 <200 nm
It is characterized by satisfying.

An optical information recording medium according to the second aspect of the present invention is an optical information recording medium having a substrate on which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam. The groove has a plurality of meandering portions, and the meandering portion includes a first curved portion that curves toward the first groove adjacent to one of the lands and a second groove adjacent to the other of the lands. A second curved portion that curves toward the land, and a protruding area of the first curved portion with respect to the first groove is A1,
2.8 × 10 ⁴ nm ² <A1 <1.6 × 10 ⁵ nm ²
It is characterized by satisfying.

  In the optical information recording media according to the first and second aspects of the present invention, the light having the substrate on which the recording layer and the groove are formed in this order when viewed from the direction in which the recording and / or reproducing laser light is irradiated. Even in the information recording medium, the meandering portion of the groove can be reliably detected, and information recording on the recording layer can be performed stably.

In the first and second aspects of the present invention, the width of the groove is Wg, the length of the meandering portion is Lw, and the distance from the vertex of the first curved portion of the meandering portion to the vertex of the second curved portion. Is Wp,
350 nm ≦ Wg ≦ 460 nm
700nm ≦ Lw ≦ 1000nm
700nm ≦ Wp ≦ 1000nm
Is preferably satisfied.

  In the first and second aspects of the present invention, another substrate is laminated on the substrate via an intermediate layer, and the other substrate has a groove and a recording layer as viewed from the direction of laser light irradiation. They may be formed in order.

  In this case, the another substrate, the intermediate layer, and the substrate may be laminated in this order when viewed from the direction of the laser light irradiation.

The optical information recording medium is an optical information recording medium having a substrate in which a recording layer and a groove are formed in this order when viewed from the direction in which the recording and / or reproducing laser light is irradiated. The meandering portion has a first curved portion that curves toward the first groove adjacent to one of the lands and the second groove adjacent to the other of the lands, and curves toward the land. When the projecting amount of the first curved portion with respect to the first groove is T1, and the projecting amount of the second curved portion with respect to the land is T2,
0.8 <T1 / T2 <2.0
May be satisfied.

Next, the optical information recording medium substrate according to the third aspect of the present invention is an optical information recording in which a recording layer and a groove are formed in this order when viewed from the direction in which recording and / or reproducing laser light is irradiated. In the medium substrate, the groove has a plurality of meandering portions, and the meandering portion is adjacent to the first curved portion that curves toward the first groove adjacent to one of the lands and the other of the lands. A second curved portion that curves from the second groove toward the land, and a protruding amount of the first curved portion with respect to the first groove is T1,
100 nm <T1 <200 nm
It is characterized by satisfying.

Further, the optical information recording medium substrate according to the fourth aspect of the present invention is an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam. The groove has a plurality of meandering portions, and the meandering portions are curved toward the first groove adjacent to one of the lands, and the first curved portion adjacent to the other of the lands. A second curved portion that curves from the two grooves toward the land, and a protruding area of the first curved portion with respect to the first groove is A1,
2.8 × 10 ⁴ nm ² <A1 <1.6 × 10 ⁵ nm ²
It is characterized by satisfying.

  Thus, an optical information recording medium having a substrate in which a recording layer and a groove are formed in this order when viewed from the direction in which recording and / or reproducing laser light is irradiated, and the meandering portion of the groove is reliably detected. Therefore, an optical information recording medium that can stably record information on the recording layer can be easily realized.

The substrate for the optical information recording medium is a substrate for an optical information recording medium in which the recording layer and the groove are formed in this order when viewed from the direction in which the recording and / or reproducing laser beam is irradiated. Has a plurality of meandering portions, the meandering portion being curved toward the first groove adjacent to one of the lands, and from the second groove adjacent to the other of the lands toward the land. A second curved portion that curves, and a projection amount of the first curved portion with respect to the first groove is T1, and a projection amount of the second curved portion with respect to the land is T2,
0.8 <T2 <2.0
May be satisfied.

Next, a stamper according to a fifth aspect of the present invention produces a substrate for an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam. The groove has a plurality of meandering portions, and the meandering portion is adjacent to the first curved portion that curves toward the first groove adjacent to one of the lands and the other of the lands. A second curved portion that curves from the second groove toward the land, and a protruding amount of the first curved portion with respect to the first groove is T1,
100 nm <T1 <200 nm
It is characterized by satisfying.

The stamper according to the sixth aspect of the present invention produces a substrate for an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam. In the stamper, the groove has a plurality of meandering portions, and the meandering portion is curved toward the first groove adjacent to one of the lands, and the first curved portion adjacent to the other of the lands. A second curved portion that curves from the two grooves toward the land, and a protruding area of the first curved portion with respect to the first groove is A1,
2.8 × 10 ⁴ nm ² <A1 <1.6 × 10 ⁵ nm ²
It is characterized by satisfying.

  Thus, an optical information recording medium having a substrate in which a recording layer and a groove are formed in this order when viewed from the direction in which recording and / or reproducing laser light is irradiated, and the meandering portion of the groove is reliably detected. Thus, an optical information recording medium capable of stably recording information on the recording layer can be easily produced.

The stamper is a stamper for producing a substrate for an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from a direction in which recording and / or reproducing laser light is irradiated. Has a plurality of meandering portions, the meandering portion being curved toward the first groove adjacent to one of the lands, and from the second groove adjacent to the other of the lands toward the land. A second curved portion that curves, and a projection amount of the first curved portion with respect to the first groove is T1, and a projection amount of the second curved portion with respect to the land is T2,
0.8 <T1 / T2 <2.0
May be satisfied.

Next, in the seventh method for manufacturing an optical information recording medium according to the present invention, the first substrate, the intermediate layer, and the second substrate are arranged in this order as viewed from the direction in which the recording and / or reproducing laser light is irradiated. In the method for manufacturing a laminated optical information recording medium, a step of producing the first substrate on which grooves and lands are formed using a first stamper, and the grooves and lands of the first substrate are formed. Forming a recording layer on the formed surface, forming a second substrate on which grooves and lands are formed using a second stamper, and forming the grooves and lands in the second substrate. Forming a recording layer on the formed surface, and the groove formed on the second substrate when the second substrate is produced by the second stamper has a plurality of meander parts, and the meander part Is the first adjacent to one of the lands A first curved portion that curves toward the lube, and a second curved portion that curves toward the land from the second groove adjacent to the other of the lands, and the first curved portion with respect to the first groove When the protruding amount is T1,
100 nm <T1 <200 nm
It is characterized by satisfying.

Further, in the manufacturing method of the optical information recording medium according to the eighth aspect of the present invention, the first substrate, the intermediate layer, and the second substrate are laminated in this order when viewed from the direction in which the recording and / or reproducing laser beam is irradiated. In the method of manufacturing an optical information recording medium, the step of producing the first substrate on which grooves and lands are formed using a first stamper, and the grooves and the lands are formed on the first substrate. A step of forming a recording layer on the surface, a step of manufacturing the second substrate on which grooves and lands are formed using a second stamper, and the grooves and the lands of the second substrate are formed. Forming a recording layer on the surface, and the groove formed on the second substrate when the second substrate is manufactured by the second stamper has a plurality of meandering portions, , First adjacent to one of the lands A first curved portion that curves toward the lube, and a second curved portion that curves toward the land from the second groove adjacent to the other of the lands, and the first curved portion with respect to the first groove When the protruding area is A1,
2.8 × 10 ⁴ nm ² <A1 <1.6 × 10 ⁵ nm ²
It is characterized by satisfying.

  Thus, an optical information recording medium having a substrate in which a recording layer and a groove are formed in this order when viewed from the direction in which recording and / or reproducing laser light is irradiated, and the meandering portion of the groove is reliably detected. Thus, an optical information recording medium capable of stably recording information on the recording layer can be easily produced.

The method for producing an optical information recording medium is an optical information recording medium in which a first substrate, an intermediate layer, and a second substrate are laminated in this order when viewed from the direction in which recording and / or reproducing laser light is irradiated. In the manufacturing method, a step of producing the first substrate on which grooves and lands are formed using a first stamper, and a recording layer is formed on a surface of the first substrate on which the grooves and lands are formed. Forming a recording layer on a surface of the second substrate on which the groove and the land are formed, and a step of forming the second substrate on which the groove and the land are formed using a second stamper. And the groove formed on the second substrate when the second substrate is produced by the second stamper has a plurality of meandering portions, and the meandering portion is adjacent to one of the lands. Bay towards the first groove And a second curved portion that curves toward the land from the second groove adjacent to the other of the lands, and the amount of protrusion of the first curved portion with respect to the first groove is T1, When the amount of protrusion of the second curved portion with respect to the land is T2,
0.8 <T1 / T2 <2.0
May be satisfied.

Next, a stamper manufacturing method according to a ninth aspect of the present invention is for an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam. In the stamper manufacturing method for manufacturing a substrate, the method includes a step of selectively etching the stamper original plate to form a stamper having unevenness on a surface, and the unevenness is When making the substrate,
(1) the groove has a plurality of meandering portions;
(2) The meandering portion has a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curve that curves toward the land from the second groove adjacent to the other of the lands. Having a part,
(3) When the protruding amount of the first curved portion with respect to the first groove is T1,
100 nm <T1 <200 nm
The groove satisfying the above is a shape transferred to the substrate.

A stamper manufacturing method according to a tenth aspect of the present invention is a substrate for an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam. In the method of manufacturing a stamper for manufacturing, a step of selectively etching the stamper original plate to form a stamper having unevenness on the surface, the unevenness is formed on the substrate by the stamper. When making
(1) the groove has a plurality of meandering portions;
(2) The meandering portion has a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curve that curves toward the land from the second groove adjacent to the other of the lands. Having a part,
(3) When the projected area of the first curved portion with respect to the first groove is A1,
2.8 × 10 ⁴ nm ² <A1 <1.6 × 10 ⁵ nm ²
The groove satisfying the above is a shape transferred to the substrate.

  Thus, an optical information recording medium having a substrate in which a recording layer and a groove are formed in this order when viewed from the direction in which recording and / or reproducing laser light is irradiated, and the meandering portion of the groove is reliably detected. Thus, an optical information recording medium capable of stably recording information on the recording layer can be easily produced.

Note that the stamper manufacturing method includes a stamper for manufacturing a substrate for an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam. In the manufacturing method, the method includes a step of selectively etching the stamper original plate to produce a stamper having irregularities on the surface, and the irregularities are produced when the substrate is produced by the stamper.
(1) the groove has a plurality of meandering portions;
(2) The meandering portion has a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curve that curves toward the land from the second groove adjacent to the other of the lands. Having a part,
(3) When the protruding amount of the first curved portion with respect to the first groove is T1, and the protruding amount of the second curved portion with respect to the land is T2,
0.8 <T1 / T2 <2.0
The groove satisfying the condition may be transferred to the substrate.

  As described above, according to the optical information recording medium of the present invention, the light having the substrate on which the recording layer and the groove are formed in this order when viewed from the direction in which the recording and / or reproducing laser light is irradiated. Even in the information recording medium, the meandering portion of the groove can be reliably detected, and information recording on the recording layer can be performed stably.

  Further, according to the substrate for optical information recording medium according to the present invention, the optical information having the substrate on which the recording layer and the groove are formed in this order when viewed from the direction in which the recording and / or reproducing laser light is irradiated. An optical information recording medium that is a recording medium and can reliably detect the meandering portion of the groove and can stably record information on the recording layer can be easily realized.

  The stamper according to the present invention is an optical information recording medium having a substrate in which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam. In addition, the meandering portion of the groove can be reliably detected, and information recording on the recording layer can be performed stably.

  Further, according to the method for manufacturing an optical information recording medium and the method for manufacturing a stamper according to the present invention, the recording layer and the groove are formed in this order when viewed from the direction in which the recording and / or reproducing laser light is irradiated. An optical information recording medium having a substrate, which can reliably detect a meandering portion of a groove and can stably record information on a recording layer, can be easily manufactured. it can.

  Hereinafter, an optical information recording medium, a substrate for an optical information recording medium, a stamper, an optical information recording medium manufacturing method, and a stamper manufacturing method according to the present invention are applied to an optical disc having two information recording layers. An example will be described with reference to FIGS.

  First, as shown in FIG. 1, the optical disc 10A according to the first embodiment includes a first substrate 14 having a first pregroove 12 formed on the surface and a second pregroove 16 formed on the surface. The two substrates 18 have a configuration in which the intermediate layer 20 is bonded.

  That is, as shown in FIG. 2, the first information recording layer 22 is formed on the surface of the first substrate 14 along the unevenness of the first pregroove 12, and the semi-transparent reflection is formed on the first information recording layer 22. Layer 24 is formed.

  As shown in FIG. 3, a reflective layer 26 is formed on the surface of the second substrate 18 along the irregularities of the second pregroove 16, and a second information recording layer 28 is formed on the reflective layer 26. A barrier layer 30 is formed on the second information recording layer 28.

  Then, when the first substrate 14 and the second substrate 18 are bonded together, as shown in FIG. 1, the first information recording layer 22 formed on the first substrate 14 and the first information recording layer 22 formed on the second substrate 18 are formed. The optical disk 10A according to the first embodiment is configured by causing the two information recording layers 28 to face each other and bonding them with the intermediate layer 20 interposed between the first substrate 14 and the second substrate 18. Is done.

  When recording information on the first information recording layer 22, the recording laser beam 32 is irradiated in the direction from the end surface 14 a of the first substrate 14 toward the first information recording layer 22, and the laser beam 32 is irradiated with the first laser beam 32. Information (pits) is recorded by forming an image on the information recording layer 22. At this time, information is recorded in a portion of the first information recording layer 22 corresponding to the groove 34 of the first pre-groove 12. As the recording laser beam 32, a semiconductor laser beam having an oscillation wavelength in the range of 600 nm to 700 nm (preferably 620 to 680 nm, more preferably 630 to 660 nm) is used.

  When information is recorded on the second information recording layer 28, the recording laser beam 32 is irradiated in the direction from the end surface 14a of the first substrate 14 toward the second information recording layer 28, and the laser beam 32 is emitted from the second information recording layer 28 to the second information recording layer 28. Information (pits) is recorded by forming an image on the information recording layer 28. At this time, information is recorded in a portion of the second information recording layer 28 corresponding to the land 36 of the second pregroove 16.

  Therefore, the information recorded in the first information recording layer 22 and the information recorded in the second information recording layer 28 are provided by interposing the intermediate layer 20 between the first information recording layer 22 and the second information recording layer 28. Information interference can be prevented, and a good recording / reproducing signal can be obtained by the first information recording layer 22 and the second information recording layer 28.

  By the way, in the recording of information on the first information recording layer 22, the first pregroove 12 and the first information recording layer 22 are formed in this order when viewed from the direction in which the laser beam 32 is irradiated. Therefore, when the first pre-groove 12 is wobbled, the wobbling shape can be reliably detected with the reproduction laser beam.

  On the other hand, in the recording of information on the second information recording layer 28, the second information recording layer 28 and the second pregroove 16 are formed in this order when viewed from the direction in which the laser beam 32 is irradiated. Therefore, when the second pregroove 16 is wobbled, the wobbling shape is partially hidden by the pits recorded in the second information recording layer 28 and cannot be reliably detected by the reproduction laser beam. Inconvenience may occur.

  Therefore, in the optical disc 10A according to the first embodiment, the shape of the second pregroove 16 formed on the surface of the second substrate 18 is configured as follows, and the wobbling of the second pregroove 16 is performed. Can be reliably detected. Of course, the shape of the first pregroove 12 formed on the surface of the first substrate 14 may also be configured as follows.

  That is, as shown in FIG. 4, the second pregroove 16 has a plurality of meandering portions 40 so as to enlarge and show a part of the second pregroove 16. In FIG. 4, one meandering portion 40 is representatively shown. FIG. 4 shows one land 36 and first and second grooves 42 a and 42 b arranged on both sides of the land 36.

  The meandering portion 40 is curved toward the land 36 from the first curved portion 44 curved toward the first groove 42 a adjacent to one of the lands 36 and the second groove 42 b adjacent to the other of the lands 36. 2 curved portions 46.

And when the protrusion amount with respect to the 1st groove 42a of the 1st curved part 44 is set to T1,
100 nm <T1 <200 nm (1)
It is formed to satisfy.

Alternatively, when the projecting area of the first curved portion 44 with respect to the first groove 42a (region indicated by hatching) is A1,
2.8 × 10 ⁴ nm ² <A1 <1.6 × 10 ⁵ nm ² (2)
It is formed to satisfy.

  Of course, the expressions (1) and (2) may be satisfied.

Further, when the protruding amount of the first curved portion 44 with respect to the first groove 42a is T1, and the protruding amount of the second curved portion 46 with respect to the land 36 is T2,
0.8 <T1 / T2 <2.0 (3)
It may be formed so as to satisfy

  In this case, the expression (2) and the expression (3) are satisfied, the expression (1) and the expression (3) are satisfied, or the expressions (1), (2) and (3). It may be formed so as to satisfy the above.

Here, when the width of the land 36 is Wg, the length of the meandering portion 40 is Lw, and the distance from the vertex of the first curved portion 44 of the meandering portion 40 to the vertex of the second curved portion 46 is Wp,
350 nm ≦ Wg ≦ 460 nm (4)
700 nm ≦ Lw ≦ 1000 nm (5)
700 nm ≦ Wp ≦ 1000 nm (6)
Is preferably satisfied.

  Thus, even in the optical disc 10A in which the second information recording layer 28 and the second pregroove 16 are formed in this order when viewed from the direction of irradiation with the recording laser beam 32 and / or the reproduction laser beam. The meandering portion 40 of the second pregroove 16 can be reliably detected, and information recording on the second information recording layer 28 can be performed stably.

  Here, a manufacturing method of the optical disc 10A according to the first embodiment will be described with reference to FIGS. 1 to 3 and FIG.

  First, in step S1 in FIG. 5, a first stamper for producing the first substrate 14 is produced. In this case, the first original plate to be the first stamper is selectively etched to produce a first stamper having irregularities on the surface. For example, the first stamper is manufactured by performing high-precision mastering by cutting with a DUV (wavelength 330 nm or less, deep ultraviolet) laser or EB (electron beam) on the first original plate.

  At this time, the first pregroove 12 is formed on the surface of the first substrate 14 when the first substrate 14 is formed by, for example, injection molding or extrusion molding of a resin material with the first stamper completed. First, the first stamper is manufactured by performing mastering on the first original plate.

  Further, in step S2 of FIG. 5, a second stamper for producing the second substrate 18 is produced. In this case, the second original plate to be the second stamper is selectively etched to produce a second stamper having irregularities on the surface. For example, the second stamper is manufactured by performing high-precision mastering on the second original plate by cutting with a DUV (wavelength of 330 nm or less, deep ultraviolet) laser or EB (electron beam).

  At this time, when the second substrate 18 is formed, for example, by injection molding or extrusion molding of a resin material with the completed second stamper, at least the above-described formula (1), ( 2) Mastering is performed on the second original plate so that the second pregroove 16 having the meandering portion 40 satisfying any one of the expressions, and more preferably satisfying the expressions (4) to (6) is formed. A second stamper is produced.

  Thereafter, in step S3 of FIG. 5, the first substrate 14 is manufactured by injection molding a resin material such as polycarbonate on the first stamper. At this time, the unevenness of the first stamper is transferred to the surface of the first substrate 14 to form the first pregroove 12.

  Further, in step S4 of FIG. 5, the second substrate 18 is manufactured by injection molding or extrusion molding of a resin material such as polycarbonate for the second stamper. At this time, the unevenness of the second stamper is transferred to the surface of the second substrate 18 and satisfies at least one of the above-described formulas (1) and (2), and more preferably formulas (4) to (6). A second pregroove 16 having a meandering portion 40 that satisfies the equation is formed.

  In the above example, the first substrate 14 and the second substrate 18 are manufactured by injection molding or extrusion molding of a resin material such as polycarbonate. However, the first substrate 14 having a flat surface as described below is used. The first pregroove 12 and the second pregroove 16 may be formed by forming a pregroove layer on the surface of the second substrate 18.

  As a material for the pregroove layer, a mixture of at least one monomer (or oligomer) of monoester, diester, triester and tetraester of acrylic acid and a photopolymerization initiator can be used. The formation of the pre-groove layer is, for example, when the first substrate 14 is viewed, a mixed liquid composed of the above acrylate ester and a polymerization initiator is applied on the first stamper, and the first substrate 14 is further applied on the coating liquid layer. After mounting, the coating layer is cured by irradiating ultraviolet rays through the first substrate 14 or the first stamper to fix the first substrate 14 and the coating layer. Next, by peeling the first substrate 14 from the first stamper, it is possible to obtain the first substrate 14 with the pregroove layer having the first pregroove 12 formed on the surface. The same applies to the second substrate 18. By using the second stamper, it is possible to obtain the second substrate 18 having the pregroove layer having the second pregroove 16 formed on the surface thereof.

  Thereafter, in step S <b> 5 of FIG. 5, the first information recording layer 22 is formed on the surface of the first substrate 14, and then the translucent reflective layer 24 is formed on the first information recording layer 22.

  5, the reflective layer 26 is formed on the surface of the second substrate 18, the second information recording layer 28 is formed on the reflective layer 26, and the second information recording layer 28 is further formed. The barrier layer 30 is formed.

  Thereafter, in step S7 of FIG. 5, the first substrate 14 and the second substrate 18 are bonded together. At this time, the first information recording layer 22 formed on the first substrate 14 and the second information recording layer 28 formed on the second substrate 18 are opposed to each other, and further, the first substrate 14 and the second substrate The intermediate layer 20 is interposed between the two layers 18 and 18. By this bonding, the optical disc 10A according to the first embodiment is completed.

  Thus, by manufacturing the optical disc 10A using the second stamper and the second substrate 18, the second information recording layer is viewed from the direction in which the recording laser beam 32 and / or the reproduction laser beam is irradiated. 28 and the second pregroove 16 are formed in this order, and the meandering portion 40 of the second pregroove 16 can be reliably detected, and information recording on the second information recording layer 28 can be stably performed. The optical disc 10A according to the first embodiment that can be performed can be easily manufactured.

  The optical disc is suitable as DVD-R or DVD + R. In this case, in the DVD-R, the groove is wobbled at 100 to 200 KHz, and in the DVD + R, the groove is wobbled at 800 to 900 KHz.

  Next, an optical disc 10B according to a second embodiment will be described with reference to FIG.

  The optical disc 10B according to the second embodiment has substantially the same configuration as the optical disc 10A according to the first embodiment described above, but the surface of the second substrate 18 is a flat surface, and instead the intermediate layer 20 Concavities and convexities are formed at the interface between the reflective layer 26 and the barrier layer 30. The irregularities are reflected on the surface of the reflective layer 26 and function as the second pregroove 16 of the second information recording layer 28. The difference is that an adhesive layer 48 is interposed between the two substrates 18.

  Also in the optical disc 10B according to the second embodiment, the second information recording layer 28 and the second pregroove 16 are formed in this direction when viewed from the direction of irradiation with the recording laser beam 32 and / or the reproduction laser beam. Even in the case of optical disks formed in order, the meandering portion 40 of the second pregroove 16 can be reliably detected, and information recording on the second information recording layer 28 can be performed stably. In terms of performance, the optical disc 10A according to the first embodiment is preferable.

  Here, a manufacturing method of the optical disc 10B according to the second embodiment will be described with reference to FIGS.

  First, in step S101 in FIG. 7, a first stamper for producing the first substrate 14 is produced. Since this step S101 performs the same process as the above-described step S1, the redundant description thereof will be omitted.

  Further, in step S102 of FIG. 7, a second stamper for producing the second substrate 18 is produced. At this time, when the second substrate 18 is formed, for example, by injection molding a resin material with the completed second stamper, the second stamper is manufactured so that the surface of the second substrate 18 becomes a flat surface.

  Further, in step S103 of FIG. 7, a third stamper for forming irregularities on the surface of the intermediate layer 20 is produced. In this case, the third original plate to be the third stamper is selectively etched to produce a third stamper having irregularities on the surface. For example, the third stamper is manufactured by performing high-precision mastering on the third original plate by cutting with a DUV (wavelength of 330 nm or less, deep ultraviolet) laser or EB (electron beam).

  At this time, when the unevenness is formed on the surface of the intermediate layer 20 by the completed third stamper and the barrier layer 30, the second information recording layer 28, and the reflective layer 26 are further formed on the intermediate layer 20, the reflective layer 26 The second pregroove 16 having the meandering portion 40 satisfying at least one of the above-described formulas (1) and (2), more preferably satisfying the formulas (4) to (6) is formed on the surface of As described above, the third stamper is manufactured by performing mastering on the third original plate.

  Thereafter, in step S104 of FIG. 7, the first substrate 14 is manufactured by injection molding or extrusion molding of a resin material with respect to the first stamper. At this time, the unevenness of the first stamper is transferred to the surface of the first substrate 14 to form the first pregroove 12.

  Further, in step S105 of FIG. 7, the second substrate 18 is manufactured by injection molding or extrusion molding of a resin material with respect to the second stamper. At this time, the 2nd board | substrate 18 (refer FIG. 6) by which the surface was made into the flat surface is produced.

  Thereafter, in step S106 of FIG. 7, the first information recording layer 22 is formed on the surface of the first substrate 14, and then the semitransparent reflective layer 24 is formed on the first information recording layer 22, and further the semitransparent reflection is performed. An intermediate layer 20 is formed on the layer 24.

  Thereafter, in step S107 of FIG. 7, the third stamper is pressed against the intermediate layer 20 formed on the first substrate. At this time, the unevenness of the third stamper is transferred to the surface of the intermediate layer 20.

  7, the barrier layer 30 is formed on the intermediate layer 20, the second information recording layer 28 is then formed on the barrier layer 30, and the reflective layer is further formed on the second information recording layer 28. 26 is formed. At this time, the reflective layer 26 is formed by reflecting the unevenness of the intermediate layer 20, and satisfies at least one of the above-described formulas (1) and (2), and more preferably formulas (4) to (6). A second pregroove 16 having a meandering portion 40 that satisfies the equation is formed.

  Thereafter, in step S109 of FIG. 7, the adhesive layer 48 is formed on the reflective layer 26, and then the second substrate 18 is adhered on the adhesive layer 48, whereby the optical disc 10B according to the second embodiment is completed. To do.

  In this way, by manufacturing the optical disc 10B using the third stamper, the second information recording layer 28 and the second pre-recording layer 28 are seen from the direction of irradiation with the recording laser beam 32 and / or the reproduction laser beam. An optical disk in which the grooves 16 are formed in this order, the meandering portion 40 of the second pre-groove 16 can be reliably detected, and information recording on the second information recording layer 28 can be performed stably. The optical disc 10B according to the second embodiment can be easily manufactured.

  Next, materials and the like of each layer constituting the optical disks 10A and 10B according to the first and second embodiments will be described.

  First, as the first substrate 14 and the second substrate 18, various materials used as substrate materials for conventional optical discs can be arbitrarily selected and used.

  Specifically, glass; acrylic resin such as polycarbonate and polymethyl methacrylate; vinyl chloride resin such as polyvinyl chloride and vinyl chloride copolymer; epoxy resin; amorphous polyolefin; polyester; metal such as aluminum; These may be used together if desired.

  Among the above materials, thermoplastic resins such as amorphous polyolefin and polycarbonate are preferable, and polycarbonate is particularly preferable from the viewpoints of moisture resistance, dimensional stability, and low price.

  When these resins are used, the first substrate 14 and the second substrate 18 can be manufactured by injection molding.

  Moreover, the thickness of the 1st board | substrate 14 and the 2nd board | substrate 18 is the range of 0.7-2 mm, It is preferable that it is the range of 0.9-1.6 mm, and is 1.0-1.3 mm. It is more preferable.

  In addition, the upper limit of the track pitch of the first pregroove 12 formed on the first substrate 14 and the second pregroove 16 formed on the second substrate 18 is preferably 500 nm or less, and 420 nm or less. Is more preferably 370 nm or less, and particularly preferably 330 nm or less. Further, the lower limit is preferably 50 nm or more, more preferably 100 nm or more, further preferably 200 nm or more, and particularly preferably 260 nm or more.

  The upper limit of the widths (half widths) of the first pregroove 12 and the second pregroove 16 is preferably 250 nm or less, more preferably 200 nm or less, further preferably 170 nm or less, and 150 nm or less. It is particularly preferred that Further, the lower limit is preferably 23 nm or more, more preferably 50 nm or more, further preferably 80 nm or more, and particularly preferably 100 nm or more.

  The (groove) depth of the first pregroove 12 and the second pregroove 16 is preferably 150 nm or less, more preferably 100 nm or less, even more preferably 70 nm or less, and even more preferably 50 nm or less. It is particularly preferred that Further, the lower limit is preferably 5 nm or more, more preferably 10 nm or more, further preferably 20 nm or more, and particularly preferably 28 nm or more.

  The upper limit of the angles of the first pregroove 12 and the second pregroove 16 is preferably 80 ° or less, more preferably 70 ° or less, further preferably 60 ° or less, and 50 ° or less. It is particularly preferred that Further, the lower limit value is preferably 20 ° or more, more preferably 30 ° or more, and further preferably 40 ° or more.

  The upper limit value and the lower limit value related to the first pregroove 12 and the second pregroove 16 can be arbitrarily combined.

  The values of the first pregroove 12 and the second pregroove 16 can be measured by an AFM (atomic force microscope).

  For example, the angle of the first pregroove 12 refers to the surface of the first substrate 14 before the groove is formed, with a depth of D / 10 from the surface when the groove depth of the first pregroove 12 is D. This is an angle formed by a straight line connecting the sloped portion and the sloped portion having a height of D / 10 from the deepest portion of the groove and the surface of the first substrate 14 (bottom surface of the groove portion). The same applies to the angle of the second pregroove 16.

  Further, when the optical discs 10A and 10B according to the first and second embodiments are read-only optical discs, predetermined information is formed simultaneously with the formation of the first pregroove 12 and the second pregroove 16 described above. Is formed.

  In addition, it is preferable to form an undercoat layer on the surfaces of the first substrate 14 and the second substrate 18 for the purpose of improving the flatness and the adhesive force.

  Examples of the material for the undercoat layer include polymethyl methacrylate, acrylic acid / methacrylic acid copolymer, styrene / maleic anhydride copolymer, polyvinyl alcohol, N-methylol acrylamide, styrene / vinyl toluene copolymer, and chloro. Polymer materials such as sulfonated polyethylene, nitrocellulose, polyvinyl chloride, chlorinated polyolefin, polyester, polyimide, vinyl acetate / vinyl chloride copolymer, ethylene / vinyl acetate copolymer, polyethylene, polypropylene, polycarbonate, etc .; silane coupling Surface modifiers such as agents;

  The undercoat layer is formed by dissolving or dispersing the above materials in an appropriate solvent to prepare a coating solution, and then applying this coating solution to the substrate surface by a coating method such as spin coating, dip coating, or extrusion coating. can do. The thickness of the undercoat layer is generally in the range of 0.005 to 20 μm, and preferably in the range of 0.01 to 10 μm.

  The first information recording layer 22 and the second information recording layer 28 are preferably of a dye type containing a dye as a recording material. Examples of the recording material contained in the first information recording layer 22 and the second information recording layer 28 include organic compounds such as dyes and phase change metal compounds.

  Among these, the dye-type first information recording layer 22 and the second information recording layer 28 that can record information only once with a laser beam are preferable. The dye-type first information recording layer 22 and the second information recording layer 28 preferably contain a dye having absorption in the recording wavelength region. Examples of the dye include a cyanine dye, an oxonol dye, a metal complex dye, an azo dye, and a phthalocyanine dye, and among them, an oxonol dye is preferable. By containing an oxonol dye, stable recording / reproducing characteristics can be maintained over a long period of time.

  Here, the oxonol dye used in the first information recording layer 22 and the second information recording layer 28 will be described.

  Specific examples of the oxonol dye include F.I. M.M. Examples include those described by Harmer, Heterocyclic Compounds-Cyanine Dies and Related Compounds, John & Wiley & Sons, New York, London, 1964.

  The oxonol dye can be synthesized by a condensation reaction between a corresponding active methylene compound and a methine source (a compound used for introducing a methine group into a methine dye).

  Details of this type of compound are described in JP-B-39-22069, JP-A-43-3504, JP-A-52-38056, JP-A-54-38129, JP-A-55-10059, and JP-A-58-35544. JP, 49-99620, 52-92716, 59-16834, 63-316853, 64-40827, British Patent 1133986, US Patent Nos. 3,247,127, 4042397, 4,181,225, 5,213,956 and 5,260,179 can be referred to. Also described in JP-A-63-209995, JP-A-10-309871 and JP-A-2002-249674.

  Oxonol dyes may be used alone or in combination of two or more. Further, the above-mentioned oxonol dye and other dye compounds may be used in combination. Examples of the dye to be used in combination include azo dyes (including those complexed with metal ions), pyromethene dyes, cyanine dyes, and the like.

  The dye preferably has a thermal decomposition temperature in the range of 100 ° C to 350 ° C. Furthermore, what is in the range of 150 to 300 degreeC is preferable. Furthermore, the thing in the range of 200 to 300 degreeC is preferable.

  Complex refractive index due to optical characteristics of the amorphous film of the dye used in the first information recording layer 22 and the second information recording layer 28 ("Oxonol dye" or "Oxonol dye described above and a dye used in combination therewith") The coefficients n (real part: refractive index) and k (imaginary part: extinction coefficient) are preferably 2.0 ≦ n ≦ 3.0 and 0.005 ≦ k ≦ 0.30. More preferably, 2.1 ≦ n ≦ 2.7 and 0.01 ≦ k ≦ 0.15. Most preferably, 2.15 ≦ n ≦ 2.50 and 0.03 ≦ k ≦ 0.10.

  The first information recording layer 22 and the second information recording layer 28 can contain various anti-fading agents for further improving light resistance. Representative examples of the anti-fading agent include metal complexes, diimmonium salts, aminium salts represented by general formula (III), (IV) or (V) described in JP-A-3-224793, and JP-A-2-300287. And nitroso compounds disclosed in JP-A-2-300288 and TCNQ derivatives disclosed in JP-A-10-151861.

  The first information recording layer 22 and the second information recording layer 28 are formed by preparing a coating solution by dissolving the oxonol dye described above and, if desired, a quencher, a binder and the like in a solvent. It can be carried out by drying after coating the surface of the substrate 14 and the surface of the second substrate 18 to form a coating film. Examples of the solvent of the coating solution include esters such as butyl acetate, ethyl lactate, and cellosolve acetate; ketones such as methyl ethyl ketone, cyclohexanone, and methyl isobutyl ketone; chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane, and chloroform; dimethylformamide and the like Amides; hydrocarbons such as cyclohexane; ethers such as tetrahydrofuran, ethyl ether, dioxane; alcohols such as ethanol, n-propanol, isopropanol, n-butanol, diacetone alcohol; 2,2,3,3-tetrafluoro Fluorine solvents such as propanol; glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, etc. That.

  The said solvent can be used individually or in combination of 2 or more types in consideration of the solubility of the compound to be used. Various additives such as an antioxidant, a UV absorber, a plasticizer, and a lubricant may be further added to the coating solution depending on the purpose.

  Examples of the binder include natural organic polymer materials such as gelatin, cellulose derivatives, dextran, rosin and rubber; and hydrocarbon resins such as polyethylene, polypropylene, polystyrene and polyisobutylene; polyvinyl chloride, polyvinylidene chloride, Vinyl resins such as polyvinyl chloride / polyvinyl acetate copolymers; acrylic resins such as polymethyl acrylate and polymethyl methacrylate; polyvinyl alcohol, chlorinated polyethylene, epoxy resins, butyral resins, rubber derivatives, phenol / formaldehyde resins And synthetic organic polymers such as an initial condensate of a thermosetting resin.

  When a binder is used in combination as a material for the first information recording layer 22 and the second information recording layer 28, the amount of the binder used is generally 0.01 relative to the amount of the dye including the oxonol dye described above. It exists in the range of -50 times amount (mass ratio), Preferably it exists in the range of 0.1-5 times amount (mass ratio). The pigment concentration of the coating solution thus prepared is generally in the range of 0.01 to 10% by mass, preferably in the range of 0.1 to 5% by mass.

  Examples of the coating method include a spray method, a spin coating method, a dip method, a roll coating method, a blade coating method, a doctor roll method, and a screen printing method. Each of the first information recording layer 22 and the second information recording layer 28 may be a single layer or a multilayer. The thicknesses of the first information recording layer 22 and the second information recording layer 28 are generally in the range of 20 to 500 nm, and preferably in the range of 50 to 300 nm.

  Next, the translucent reflective layer 24 and the reflective layer 26 will be described. The light reflective material that is a material of the reflective layer 26 is a material having a high reflectance with respect to laser light. Examples thereof include Mg, Se, and Y. Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Co, Ni, Ru, Rh, Pd, Ir, Pt, Cu, Ag, Au, Zn, Cd, Al , Ga, In, Si, Ge, Te, Pb, Po, Sn, Bi, and other metals and metalloids, and stainless steel.

  Among these, preferred are Cr, Ni, Pt, Cu, Ag, Au, Al, and stainless steel, and particularly preferred is Ag. These substances may be used alone or in combination of two or more or as an alloy. The reflective layer 26 can be formed on the first information recording layer 22, the second information recording layer 28, and the second substrate 18, for example, by vapor deposition, sputtering, or ion plating of the reflective material.

  And it is preferable that the layer thickness of the translucent reflective layer 24 exists in the range of 2-150 nm. The thickness of the reflective layer 26 is generally in the range of 10 to 300 nm, preferably in the range of 50 to 200 nm.

  Next, the barrier layer 30 is provided for the purpose of physically and chemically protecting the second information recording layer 28 and the like. The barrier layer 30 is provided in the first substrate 14 and the second substrate 18 in a portion where the first information recording layer 22 and the second information recording layer 28 are not provided for the purpose of improving scratch resistance and moisture resistance. May be.

Examples of the material used for the barrier layer 30 include inorganic substances such as SiO, SiO ₂ , MgF ₂ , SnO ₂ , Si ₃ N ₄ , and ZnO—Ga ₂ O ₃ ; thermoplastic resins, thermosetting resins, and UV curing. Organic substances such as a conductive resin;

  The barrier layer 30 can be provided by a method such as vacuum deposition, sputtering, or coating. Moreover, when using a thermoplastic resin and a thermosetting resin, it can also form by preparing the coating liquid which melt | dissolved these in the appropriate solvent, apply | coating this coating liquid, and drying. In the case of a UV curable resin, it can also be formed by preparing a coating solution as it is or by dissolving it in an appropriate solvent, and then applying the coating solution and curing it by irradiating with UV light. In these coating liquids, various additives such as an antistatic agent, an antioxidant, and a UV absorber may be added according to the purpose. The layer thickness of the barrier layer 30 is generally in the range of 1 nm to 10 μm.

  Next, as described above, the intermediate layer 20 is provided at least between the first information recording layer 22 and the second information recording layer 28.

Examples of the material for the intermediate layer 20 and the adhesive layer 48 include thermoplastic resins, thermosetting resins, electron beam curable resins, ultraviolet curable resins, pressure-sensitive double-sided tapes, and inorganic materials such as SiO ₂ . These materials may be used alone or in combination, and may be used not only as a single layer but also as a multilayer film. Such an intermediate layer 20 can be formed by spin coating, casting, or sputtering. The thickness of the intermediate layer 20 is preferably 5 to 100 μm, more preferably 10 to 70 μm.

  Here, experimental examples in which AR (aperture ratio:%) and PIE (PI error: pieces) are evaluated in Examples 1 to 5 and Comparative Examples 1 to 3 will be described.

  First, the contents of Examples 1 to 5 and Comparative Examples 1 to 3 are as follows.

Example 1
A polycarbonate resin is injection-molded by using the first stamper, so that the spiral first pregroove 12 (depth 120 nm, groove width 365 nm, track pitch 0.74 μm) is 0.575 mm thick and 120 mm in diameter. The substrate was molded into a first substrate 14 for forming the first information recording layer 22.

  Thereafter, an oxonol dye represented by the following chemical formula (Chemical Formula 1) and an oxonol dye represented by the following chemical formula (Chemical Formula 2) were mixed at a ratio of 90:10, and 1.00 g of the mixed dye was mixed with 2, 2, 3 , 3-Tetrafluoro-propanol A coating solution dissolved in 100 ml is prepared, and this coating solution is applied onto the surface of the first substrate 14 on which the first pregroove 12 is formed by the spin coating method. Layer 22 was formed.

  Next, an AgBiNd alloy (target composition: Ag = 99.45 at%, Nd = 0.35 at%, Cu = 0.20 at%) is sputtered on the first information recording layer 22 to produce a semitransparent reflection having a layer thickness of 13 nm. Layer 24 was formed. Thereby, the first substrate 14 having the first information recording layer 22 was obtained.

  On the other hand, by molding the polycarbonate resin using the second stamper, a thickness of 0.600 mm having a spiral second pregroove 16 (depth 30 nm, land width 440 nm, track pitch 0.74 μm), This was formed into a substrate having a diameter of 120 mm, and this was used as the second substrate 18 for forming the second information recording layer 28.

  In Example 1, the shape of the second pregroove 16 formed on the second substrate 18 is as follows: T1 in the above-described equation (1) is 120 nm, T2 in the equation (3) is 110 nm, and the length Lw of the meandering portion 40 Is 800 nm (T1 / T2 = about 1.091), and the uneven shape formed on the second stamper has a value corresponding to T1 in the above-described equation (1) of 138 nm and corresponds to T2 in the equation (3). The value to be obtained was 127 nm (T1 / T2 = about 1.087).

  That is, Example 1 satisfies at least the expressions (1), (3), (4), and (5) described above.

  Next, an AgBiNd alloy (target composition: Ag = 99.45 at%, Nd = 0.35 at%, Cu = 0.20 at%) is formed on the surface of the second substrate 18 where the second pregroove 16 is formed. A reflective layer 26 having a layer thickness of 120 nm was formed by sputtering.

  Further, a coating solution in which 2.00 g of the oxonol dye represented by the above chemical formula (Chemical Formula 1) was dissolved in 100 ml of 2,2,3,3-tetrafluoro-propanol was prepared, and this coating solution was subjected to second coating by spin coating. The second information recording layer 28 was formed on the surface of the substrate 18 on which the reflective layer 26 was formed by applying the laser light at the longest wavelength λmax with absorbance = 1.10.

Subsequently, ZnO—Ga ₂ O ₃ (target composition: ZnO = 30 wt%, Ga ₂ O ₃ = 70 wt%) is RF-sputtered as a dye protection on the second information recording layer 28 to form a barrier layer 30 having a layer thickness of 5 nm. Formed. Thereby, the second substrate 18 having the second information recording layer 28 was obtained.

  Then, the 1st board | substrate 14 and the 2nd board | substrate 18 were bonded together using the ultraviolet curing resin (Dicure Clear SD640 Dainippon Ink and Chemicals make) as an adhesive agent, and the optical disk was obtained. The thickness of this adhesive layer, that is, the intermediate layer 20 was 50 μm.

(Example 2)
In the first embodiment, among the shapes of the second pregroove 16 formed on the second substrate 18, T1 in the above-described equation (1) is 150 nm, T2 in the equation (3) is 100 nm, and the length Lw of the meandering portion 40 is Lw. Is 800 nm (T1 / T2 = 1.5), and among the uneven shapes formed in the second stamper, the value corresponding to T1 in the above-described equation (1) corresponds to 173 nm, and corresponds to T2 in the equation (3). The value was 115 nm (T1 / T2 = 1.504).

  That is, Example 2 satisfies at least the expressions (1), (4), and (5) described above.

(Example 3)
In Example 1, among the shapes of the second pregrooves 16 formed on the second substrate 18, T1 in the above-described equation (1) is 190 nm, T2 in the equation (3) is 160 nm, and the length Lw of the meandering portion 40 Is set to 800 nm (T1 / T2 = 1.186), and among the uneven shapes formed on the second stamper, the value corresponding to T1 in the above-described equation (1) corresponds to 219 nm, and corresponds to T2 in the equation (3). The value was 184 nm (T1 / T2 = about 1.190).

  That is, Example 3 satisfies at least the expressions (1), (3), (4), and (5) described above.

Example 4
In the first embodiment, among the shapes of the second pregroove 16 formed on the second substrate 18, T1 in the above-described equation (1) is 150 nm, T2 in the equation (3) is 130 nm, and the length Lw of the meandering portion 40 is Lw. Is 900 nm (T1 / T2 = 1.154), and among the uneven shapes formed on the second stamper, the value corresponding to T1 in the above-described expression (1) corresponds to 173 nm, and corresponds to T2 in the expression (3). The value was 150 nm (T1 / T2 = 1.153).

  That is, Example 3 satisfies at least the expressions (1), (3), (4), and (5) described above.

(Example 5)
In Example 1, among the shapes of the second pregrooves 16 formed on the second substrate 18, T1 in the above-described equation (1) is 150 nm, T2 in the equation (3) is 110 nm, and the length Lw of the meandering portion 40 Is set to 1000 nm (T1 / T2 = 1.364), and among the uneven shapes formed on the second stamper, the value corresponding to T1 in the above-described equation (1) corresponds to 173 nm, and corresponds to T2 in the equation (3). The value was 127 nm (T1 / T2 = 1.362).

  That is, Example 5 satisfies at least the expressions (1), (3), (4), and (5) described above.

(Comparative Example 1)
In Example 1, among the shapes of the second pregroove 16 formed on the second substrate 18, T1 in the above-described equation (1) is 80 nm, T2 in the equation (3) is 70 nm, and the length Lw of the meandering portion 40 is Is 900 nm (T1 / T2 = 1.143), and among the uneven shapes formed on the second stamper, the value corresponding to T1 in the above-described equation (1) corresponds to 92 nm, and corresponds to T2 in the equation (3). The value was 80.5 nm (T1 / T2 = about 1.143).

  That is, the comparative example 1 satisfies at least the above-described formulas (3), (4), and (5).

(Comparative Example 2)
In Example 1, among the shapes of the second pregroove 16 formed on the second substrate 18, T1 in the above-described equation (1) is 220 nm, T2 in the equation (3) is 200 nm, and the length Lw of the meandering portion 40 is Is 900 nm (T1 / T2 = 1.1), and among the uneven shapes formed on the second stamper, the value corresponding to T1 in the above-described expression (1) corresponds to 253 nm, and corresponds to T2 in the expression (3). The value was 230 nm (T1 / T2 = about 1.1).

  That is, the comparative example 2 satisfies at least the above-described expressions (3), (4), and (5).

(Evaluation)
And, using DDU-1000 and a multi-signal generator (manufactured by Pulstec Corporation: laser wavelength = 659.8 nm, numerical aperture of objective lens = 0.60), the linear velocity is set to 7.68-30.72 m / sec, An 8-16 modulation signal was recorded, and push-pull signal evaluation, that is, aperture ratio (AR) was evaluated. The recording laser emission pattern used (recording strategy) was optimized for each optical disc.

  Thereafter, using DDU-1000 (manufactured by Pulstec Corporation: laser wavelength = 651.0 nm, numerical aperture of the objective lens = 0.60), the linear velocity is 3.84 m / sec, reproduction is performed, and PI error is evaluated. did.

  FIG. 8 shows the evaluation results of aperture ratio (AR) and PI error in Examples 1 to 5 and Comparative Examples 1 to 3.

  In Comparative Example 1, the PI error is less than the standard value of 280, but AR is 0% because it does not satisfy the expression (1), and is extremely low.

  In Comparative Example 2, although AR is 10% or more of the standard value, since the expression (1) is not satisfied, the number of PI errors is 853, which is extremely large.

  On the other hand, in Examples 1 to 5 that satisfy at least the expressions (1), (4), and (5), the aperture ratio (AR) is 10% or more of the standard value, and the PI error Is less than the standard value of 280. Therefore, in Examples 1 to 5, both AR and PI errors that are in a trade-off relationship with each other are good values and have a good balance relationship. This indicates that information recording on the second information recording layer 28 can be performed stably. In Examples 1 to 5, the degree of modulation in double speed recording (linear velocity 7.68 m / sec) was 0.50 or more and 0.63 or less.

  The optical information recording medium, the substrate for the optical information recording medium, the stamper, the manufacturing method of the optical information recording medium, and the manufacturing method of the stamper according to the present invention are not limited to the above-described embodiments, and depart from the gist of the present invention. Of course, various configurations can be adopted.

It is sectional drawing which abbreviate | omits and shows the optical disk which concerns on 1st Embodiment. It is sectional drawing which shows a 1st board | substrate. It is sectional drawing which shows a 2nd board | substrate. It is explanatory drawing which shows the shape of the meander part formed in a 2nd pregroove. It is process drawing which shows the manufacturing method of the optical disk which concerns on 1st Embodiment. It is sectional drawing which abbreviate | omits and shows the optical disk which concerns on 2nd Embodiment. It is process drawing which shows the manufacturing method of the optical disk which concerns on 2nd Embodiment. It is a table | surface which shows the evaluation result of the aperture ratio (AR) and PI error (PIE) of Examples 1-5 and Comparative Examples 1-3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10A, 10B ... Optical disk 12 ... 1st pregroove 14 ... 1st board | substrate 16 ... 2nd pregroove 18 ... 2nd board | substrate 20 ... Intermediate | middle layer 22 ... 1st information recording layer 28 ... 2nd information recording layer 36 ... Land 40 ... Meandering part 42a ... 1st groove 42b ... 2nd groove 44 ... 1st curved part 46 ... 2nd curved part

Claims (13)

In an optical information recording medium having a substrate on which a recording layer and a groove are formed in this order when viewed from the direction in which the recording and / or reproducing laser beam is irradiated,
The groove has a plurality of meander parts,
The meandering portion includes a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curved portion that curves toward the land from the second groove adjacent to the other of the lands. Have
When the protruding amount of the first curved portion with respect to the first groove is T1,
100 nm <T1 <200 nm
An optical information recording medium characterized by satisfying In an optical information recording medium having a substrate on which a recording layer and a groove are formed in this order when viewed from the direction in which the recording and / or reproducing laser beam is irradiated,
The groove has a plurality of meander parts,
The meandering portion includes a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curved portion that curves toward the land from the second groove adjacent to the other of the lands. Have
When the protruding area of the first curved portion with respect to the first groove is A1,
2.8 × 10 ⁴ nm ² <A1 <1.6 × 10 ⁵ nm ²
An optical information recording medium characterized by satisfying The optical information recording medium according to claim 1 or 2,
When the width of the land is Wg, the length of the meandering portion is Lw, and the distance from the vertex of the first curved portion of the meandering portion to the vertex of the second curved portion is Wp,
350 nm ≦ Wg ≦ 460 nm
700nm ≦ Lw ≦ 1000nm
700nm ≦ Wp ≦ 1000nm
An optical information recording medium characterized by satisfying The optical information recording medium according to any one of claims 1 to 3,
Another substrate is laminated on the substrate via an intermediate layer,
The optical information recording medium is characterized in that a groove and a recording layer are formed in this order on the other substrate as viewed from the direction in which the laser beam is irradiated. The optical information recording medium according to claim 4,
The optical information recording medium, wherein the another substrate, the intermediate layer, and the substrate are laminated in this order when viewed from the direction of the laser light irradiation. In a substrate for an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam,
The groove has a plurality of meander parts,
The meandering portion includes a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curved portion that curves toward the land from the second groove adjacent to the other of the lands. Have
When the protruding amount of the first curved portion with respect to the first groove is T1,
100 nm <T1 <200 nm
A substrate characterized by satisfying In a substrate for an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam,
The groove has a plurality of meander parts,
The meandering portion includes a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curved portion that curves toward the land from the second groove adjacent to the other of the lands. Have
When the protruding area of the first curved portion with respect to the first groove is A1,
2.8 × 10 ⁴ nm ² <A1 <1.6 × 10 ⁵ nm ²
A substrate characterized by satisfying In a stamper for producing a substrate for an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam,
The groove has a plurality of meander parts,
The meandering portion includes a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curved portion that curves toward the land from the second groove adjacent to the other of the lands. Have
When the protruding amount of the first curved portion with respect to the first groove is T1,
100 nm <T1 <200 nm
A stamper characterized by satisfying In a stamper for producing a substrate for an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from the direction of irradiation with a recording and / or reproducing laser beam,
The groove has a plurality of meander parts,
The meandering portion includes a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curved portion that curves toward the land from the second groove adjacent to the other of the lands. Have
When the protruding area of the first curved portion with respect to the first groove is A1,
2.8 × 10 ⁴ nm ² <A1 <1.6 × 10 ⁵ nm ²
A stamper characterized by satisfying In the method of manufacturing an optical information recording medium in which the first substrate, the intermediate layer, and the second substrate are laminated in this order when viewed from the direction in which the recording and / or reproducing laser light is irradiated.
Producing the first substrate on which grooves and lands are formed using a first stamper;
Forming a recording layer on a surface of the first substrate on which the groove and the land are formed;
Producing the second substrate on which grooves and lands are formed using a second stamper;
Forming a recording layer on a surface of the second substrate on which the groove and the land are formed;
The groove formed on the second substrate when the second substrate is produced by the second stamper has a plurality of meandering portions,
The meandering portion includes a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curved portion that curves toward the land from the second groove adjacent to the other of the lands. Have
When the protruding amount of the first curved portion with respect to the first groove is T1,
100 nm <T1 <200 nm
An optical information recording medium manufacturing method characterized by satisfying In the method of manufacturing an optical information recording medium in which the first substrate, the intermediate layer, and the second substrate are laminated in this order when viewed from the direction in which the recording and / or reproducing laser light is irradiated.
Producing the first substrate on which grooves and lands are formed using a first stamper;
Forming a recording layer on a surface of the first substrate on which the groove and the land are formed;
Producing the second substrate on which grooves and lands are formed using a second stamper;
Forming a recording layer on a surface of the second substrate on which the groove and the land are formed;
The groove formed on the second substrate when the second substrate is produced by the second stamper has a plurality of meandering portions,
The meandering portion includes a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curved portion that curves toward the land from the second groove adjacent to the other of the lands. Have
When the protruding area of the first curved portion with respect to the first groove is A1,
2.8 × 10 ⁴ nm ² <A1 <1.6 × 10 ⁵ nm ²
An optical information recording medium manufacturing method characterized by satisfying In a manufacturing method of a stamper for producing a substrate for an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from a direction in which recording and / or reproducing laser light is irradiated,
Selectively etching the stamper original plate to produce a stamper having irregularities on the surface;
The irregularities are produced when the substrate is produced with the stamper.
(1) the groove has a plurality of meandering portions;
(2) The meandering portion has a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curve that curves toward the land from the second groove adjacent to the other of the lands. Having a part,
(3) When the protruding amount of the first curved portion with respect to the first groove is T1,
100 nm <T1 <200 nm
The method of manufacturing a stamper, wherein the groove satisfying the above is a shape transferred to the substrate. In a manufacturing method of a stamper for producing a substrate for an optical information recording medium in which a recording layer and a groove are formed in this order when viewed from a direction in which recording and / or reproducing laser light is irradiated,
Selectively etching the stamper original plate to produce a stamper having irregularities on the surface;
The irregularities are produced when the substrate is produced with the stamper.
(1) the groove has a plurality of meandering portions;
(2) The meandering portion has a first curved portion that curves toward the first groove adjacent to one of the lands, and a second curve that curves toward the land from the second groove adjacent to the other of the lands. Having a part,
(3) When the projected area of the first curved portion with respect to the first groove is A1,
2.8 × 10 ⁴ nm ² <A1 <1.6 × 10 ⁵ nm ²
The method of manufacturing a stamper, wherein the groove satisfying the above is a shape transferred to the substrate.

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