JP4865660B2 - Optical information recording medium - Google Patents

Description

  The present invention relates to a disc-shaped optical information recording medium, and more particularly to an optical information recording medium capable of printing or drawing on the label surface (surface opposite to the light incident surface) side of the optical information recording medium. Specifically, the present invention relates to an optical information recording medium of a type in which an area where printing or drawing can be performed on the inner peripheral side rather than an information recording area where information can be recorded by laser light irradiation.

In disc-shaped optical information recording media such as CD-R, DVD ± R, HD-DVD-R, BD (Blu-ray Disc), etc., a structure in which a recording layer and a reflective layer are formed on one surface of a light-transmitting substrate And is configured to record data on the recording layer by irradiating a laser beam from the other surface side of the light transmissive substrate. In addition, the surface of the optical information recording medium opposite to the surface irradiated with the laser light is normally used as a label surface, and characters, symbols, figures, patterns, or combinations thereof are visible on the surface. Is displayed by printing or the like.

Various optical information recording media have been proposed in which the display is performed by an ink jet printer or the like. For example, in Patent Document 1, a dummy groove is provided in a portion corresponding to a clamping area of a disc-shaped light-transmitting substrate, a reflective layer is provided, and an image is formed on a corresponding portion of the reflective layer or another substrate. An optical information recording medium provided with a layer has been proposed. The clamping area is, for example, within a range of a radius of less than 22 mm from the center of the light-transmitting substrate around a hole provided with a radius of 7.5 mm in the center of the light-transmitting substrate. An information recording area in which pregrooves are formed is provided.
JP 2004-139697 A

  However, in order to further expand the image formation region of the optical information recording medium described in the background art, for example, as shown in FIG. 5, the reflective layer 4 provided on the recording layer 3 has at least the recording layer on the inner peripheral side. 3 is formed so as to reach the dummy groove 2b beyond the inner peripheral edge 3a of the groove 4a on the surface of the reflection layer 4 provided on the pregroove 2a formation region via the recording layer 3. Since the depth of the groove 4b on the surface of the reflective layer 4 provided on the dummy groove 2b formation region without the recording layer 3 is deeper than the depth, the surface (per unit area) is visible. The intensity of light reflection is lower than that of the former, and when viewed from the label surface side, the brightness decreases in an annular manner near the inner peripheral edge of the ink receiving layer 9 (the part adjacent to the mirror part 4d). The problem is that It was.

An object of the present invention is to pay attention to the above points, and an object of the present invention is to provide an optical information recording medium capable of reducing a difference in brightness when viewed from the label surface side.

In order to achieve the above object, the present invention provides (1) an optical information recording medium having a hole in the center, on one main surface, a pregroove provided in the information recording area and an inner periphery of the information recording area. A light-transmitting substrate having a dummy groove provided on the side, a region where the pregroove is formed on the main surface of the light-transmitting substrate, and a part of the region where the dummy groove is formed A recording layer provided with a dye material applied thereon, and a reflective layer provided over the recording layer and a region where the dye material is not applied on the light-transmitting substrate. The surface has a groove reflecting the pre-groove and a groove reflecting the dummy groove. The light-transmitting substrate has a pitch larger than the pre-groove pitch of the information recording area of the light-transmitting substrate in at least a part of the area where the dye material is not applied in the area where the dummy grooves are formed. The dummy groove is provided. (... Hereinafter referred to as the first problem solving means of the present invention.)

One of the main forms of the optical information recording medium is that, in addition to the first problem solving means, (2) the light-transmitting substrate is a dye in a region where dummy grooves are formed. In the area where the material is not applied, the dummy grooves are provided at a pitch larger than the pitch of the pregrooves in the information recording area of the light transmissive substrate. (... Hereinafter referred to as the second problem solving means of the present invention.)

Further, the present invention is (3) an optical information recording medium having a hole in the center, and is provided on one main surface on a pregroove provided in the information recording area and on an inner peripheral side of the information recording area. A light-transmitting substrate having a dummy groove, and a coloring material is applied over a region of the light-transmitting substrate on which the pregroove is formed on the main surface and a part of the region on which the dummy groove is formed. A recording layer provided on the surface of the reflective layer, and on the surface of the reflective layer, the reflective layer is provided on the recording layer and on the light-transmitting substrate. The light-transmitting substrate has a groove reflecting a pre-groove and a groove reflecting the dummy groove, and the light-transmitting substrate is a light-transmitting substrate in a region where a dye material is not applied in a region where a dummy groove is formed. Information recording area pre-glue The dummy grooves are provided in the depth less than the depth. (... Hereinafter referred to as the third problem solving means of the present invention.)

Further, the present invention is (4) an optical information recording medium having a hole in the center, and is provided on one main surface on a pre-groove provided in the information recording area and on an inner peripheral side of the information recording area. A light-transmitting substrate having a dummy groove, and a coloring material is applied over a region of the light-transmitting substrate on which the pregroove is formed on the main surface and a part of the region on which the dummy groove is formed. A recording layer provided on the surface of the reflective layer, and on the surface of the reflective layer, the reflective layer is provided on the recording layer and on the light-transmitting substrate. The light-transmitting substrate has a groove reflecting a pre-groove and a groove reflecting the dummy groove, and the light-transmitting substrate is a light-transmitting substrate in a region where a dye material is not applied in a region where a dummy groove is formed. The information recording area prep Wherein a narrow half-value width than (the width of the groove in the half point of the depth of the groove) the half-width of over blanking the dummy grooves are provided. (... Hereinafter referred to as the fourth problem solving means of the present invention.)

One of the main forms of the optical information recording medium is that, in addition to any one of the first to fourth problem-solving means, (5) the light-transmitting substrate includes at least the reflective layer. It has the area | region in which the said dummy groove was formed from the position of the edge part of an inner peripheral side to an inner peripheral side. (... Hereinafter referred to as the fifth problem solving means of the present invention.)

The operation of the first problem solving means is as follows. That is, the light-transmitting substrate has a pitch larger than the pre-groove pitch of the information recording area of the light-transmitting substrate in at least a part of the area where the dye material is not applied in the area where the dummy grooves are formed. Since the dummy groove is provided, the reflection intensity of visible light per unit area of the surface of the reflective layer provided via the recording layer on the region where the pregroove is formed and the dummy groove The difference between the reflection intensity of the visible light per unit area of the surface of the reflection layer provided on the area where the dye material is not applied in the formed area is reduced.

More specifically, the dummy groove is compared with the intensity of reflection of visible light (per unit area) on the surface of the reflective layer provided via the recording layer on the region where the pregroove is formed. The presence of a groove (per unit area) that reduces the intensity of reflection of visible light (per unit area) on the surface of the reflective layer provided on the area where the pigment material is not applied. Since the frequency decreases, the degree of reduction in the reflection of visible light (per unit area) can be reduced.

The operation of the second problem solving means is as follows. That is, the light-transmitting substrate has a larger pitch than the pre-groove pitch of the information recording area of the light-transmitting substrate in the area where the dye material is not applied in the area where the dummy grooves are formed. Therefore, the light-transmitting substrate has a groove reflecting the dummy groove on the surface of the reflective layer formed on the region where the dye material is not applied in the region where the dummy groove is formed ( The degree of reduction in the reflection of visible light (per unit area) can be reduced more effectively.

The operation of the third problem solving means is as follows. That is, the light-transmitting substrate has a depth shallower than the pregroove depth of the information recording region of the light-transmitting substrate in the region where the dye material is not applied in the region where the dummy grooves are formed. Since a groove is provided, the intensity of visible light reflection per unit area and the dummy groove are formed on the surface of the reflective layer provided via the recording layer on the region where the pre-groove is formed. The difference between the intensity of reflection of visible light per unit area on the surface of the reflective layer provided on the area where the pigment material is not applied in the area is reduced.

More specifically, the dummy groove is compared with the intensity of reflection of visible light (per unit area) on the surface of the reflective layer provided via the recording layer on the region where the pregroove is formed. Since the depth of the groove, which reduces the intensity of reflection of visible light (per unit area), on the surface of the reflective layer provided on the uncoated region of the dye material in the region where is formed, is reduced. The degree of reduction in the reflection of visible light (per unit area) can be reduced.

The operation of the fourth problem solving means is as follows. That is, the light-transmitting substrate has a half-value width that is narrower than the half-value width of the pregroove in the information recording region of the light-transmitting substrate in the region where the dye material is not applied in the region where the dummy grooves are formed. Since the dummy groove is provided, the intensity of the visible light reflection per unit area on the surface of the reflective layer provided via the recording layer and the dummy groove are formed on the region where the pre-groove is formed. The difference between the reflection intensity of visible light per unit area on the surface of the reflective layer provided on the area where the pigment material is not applied in the area is reduced.

More specifically, the dummy groove is compared with the intensity of reflection of visible light (per unit area) on the surface of the reflective layer provided via the recording layer on the region where the pregroove is formed. The presence of a groove (per unit area) that reduces the intensity of reflection of visible light (per unit area) on the surface of the reflective layer provided on the area where the pigment material is not applied. Since the ratio is reduced, the degree of reduction in the reflection of visible light (per unit area) can be reduced.

The operation of the fifth problem solving means is as follows. That is, in addition to any one of the first to fourth problem solving means, the light transmissive substrate further includes the dummy groove extending from the position of the inner peripheral side of the reflective layer to the inner peripheral side. Since the formed region is provided, it is possible to further suppress the generation of a region in which the reflection of visible light is increased again in the vicinity of the inner peripheral edge of the reflective layer. For this reason, it is possible to make it difficult for the consumer to notice the difference in brightness when viewed from the label surface side.

According to the optical information recording medium of the present invention, the degree of decrease in reflection of visible light (per unit area) on the surface of the reflective layer can be reduced, so that the difference in brightness when viewed from the label surface side is reduced. Can be relaxed.
The above object and other objects, structural features, and operational effects of the present invention will become apparent from the following description and the accompanying drawings.

  Hereinafter, a first embodiment of the optical information recording medium of the present invention will be described with reference to FIG. FIG. 1 is a partially enlarged sectional view showing an outline of the internal structure of the optical information recording medium 10 of the first embodiment.

  As shown in FIG. 1, the optical information recording medium 10 of the present embodiment includes an optical disc body 11 and a dummy substrate 17 provided on the optical disc body 11 with an adhesive layer 16 interposed therebetween. Has a so-called DVD-R structure provided with a base layer 18 and an ink receiving layer 19.

More specifically, the optical disc main body 11 has a hole 12c in the center, a pregroove 12a provided in the information recording area on one main surface, and a dummy provided on the inner peripheral side of the information recording area. A light-transmitting substrate 12 having a groove 12b is provided. Then, a recording is provided in which a dye material is applied over a region where the pregroove 12a is formed on the main surface of the light transmissive substrate 12 and a part of the region where the dummy groove 12b is formed. In the region where the dummy groove is formed on the recording layer 13 and on the light-transmitting substrate 12, the dye on the inner peripheral side beyond the edge 13a on the inner peripheral side of the recording layer 13 And a reflective layer 14 provided over a region where the material is not applied. The surface of the reflective layer 14 has a groove 14a reflecting the pre-groove 12a and a groove 14b reflecting the dummy groove 12b. The light-transmitting substrate 12 has a pitch of the pregroove 12a in the information recording area of the light-transmitting substrate 12 in at least a part of the area where the dye material is not applied in the area where the dummy grooves 12b are formed. The dummy grooves 12b are provided at a pitch P12b larger than P12a.

Further, in the present embodiment, the light-transmitting substrate 12 is a region of the pre-groove 12a in the information recording region of the light-transmitting substrate 12 in the region where the dye material is not applied in the region where the dummy groove 12b is formed. The dummy grooves 12b are provided at a pitch P12b larger than the pitch P12a.

In the present embodiment, the light-transmitting substrate 12 has a region where the dummy groove 12b is formed at least from the position of the inner peripheral edge 14c of the reflective layer 14 to the inner peripheral side.

Next, a preferred embodiment of the light transmissive substrate 12 is as follows. That is, the light transmissive substrate 12 is made of a transparent resin such as polycarbonate, polymethyl methacrylate, acrylic resin, and the like, and the light transmissive substrate 12 having a predetermined shape (in the case of an optical disc, a donut shape) by means such as injection molding. It is molded into Moreover, not only this but an ultraviolet curable resin can also be used. The thickness is preferably less than 0.6 mm.

Next, a preferred embodiment of the pregroove 12a is as follows. That is, the pregroove 12a is preferably formed simultaneously with the injection molding of the light transmissive substrate 12, and the pitch is 0.74 μm as a standard.

Next, a preferred embodiment of the dummy groove 12b is as follows. That is, the dummy groove 12b can be provided on the inner peripheral side of the pregroove 12a continuously or independently of the pregroove 12a. Further, the dummy groove 12b may be continuous in a circular shape from the inner periphery to the outer periphery in the same manner as the pre-groove 12a. However, the present invention is not limited to this. For example, a plurality of annular grooves may be used. It may be arranged concentrically. The dummy groove 12b is preferably formed simultaneously with the injection molding of the light-transmitting substrate 12, like the pre-groove 12a.

Next, a preferred embodiment of the recording layer 13 is as follows. That is, the recording layer 13 contains an organic dye, and pits are formed by irradiation with laser light having a predetermined wavelength to record data. As the organic dye, phthalocyanine dyes, cyanine dyes, azo dyes and the like are preferable. Data information such as music, images, and computer programs can be recorded and / or reproduced on the recording layer 13 by irradiation with the laser beam. The recording layer 13 is preferably provided by applying a dye material such as a solution containing the dye or an ink on the light-transmitting substrate 12 by means such as a screen printing method or a spin coating method.

Next, a preferred embodiment of the reflective layer 14 is as follows. That is, the reflection layer 14 reflects laser light for data recording and / or reproduction, and is made of a metal film such as Au, Al, Ag, Cu, or Pd, an alloy film of these metals, or these films. An alloy film in which a trace component is added to a metal is preferable, and is formed on the recording layer by means such as sputtering or vacuum deposition.

Next, a preferred embodiment of the adhesive layer 16 is as follows. That is, the adhesive layer 16 is preferably composed mainly of an epoxy-based or other reactive curable resin. The adhesive layer 16 may be formed on the recording layer of the optical disc body and / or the dummy by means such as spin coating or screen printing. After coating on the lower surface of the substrate, the optical disc main body and the dummy substrate are joined together by an adhesive layer 16 to obtain a disc-shaped optical information recording medium in which two substrates are bonded together.

Next, a preferred embodiment of the dummy substrate 17 is as follows. That is, the same material as the light transmissive substrate 12 can be used as the dummy substrate 17. As a result, the DVD-R bonding process can be used to integrate the information recording area created on the light transmissive substrate 12 with the underlying layer 18 and the ink receiving layer 19 formed on the dummy substrate 17.

Next, a preferred embodiment of the base layer 18 is as follows. That is, the base layer 18 is preferably composed mainly of an ultraviolet curable resin and a pigment. For example, an ultraviolet curable ink containing an ultraviolet curable resin and a pigment is screen printed or spin coated. The printing film can be printed, and the printed film can be formed by UV curing.
This underlayer 18 prevents the metallic glossy surface of the reflective layer 14 from being exposed when the adhesive layer 16, the dummy substrate 17, and the ink receiving layer 19 described later are all transparent. It is preferable to provide in.

Next, a preferred embodiment of the ink receiving layer 19 is as follows. That is, the ink receiving layer 19 is preferably composed mainly of an ultraviolet curable resin. For example, the ultraviolet curable resin, other binder components, a viscosity modifier, a pigment and other components are mixed. The ultraviolet curable ink thus obtained is printed by means such as a screen printing method or a spin coating method, and then cured by irradiating with ultraviolet rays to form directly on the dummy substrate 17 or via the underlayer 18. Is done.
Examples of the pigment include organic and inorganic coloring pigments, inorganic fillers such as silica, alumina, aluminum hydroxide, and clay, or organic fillers such as acrylic beads, nylon beads, and rubber fine particles. Or you may use arbitrary multiple types together.

Next, a preferred embodiment of the pitch P12b of the dummy groove 12b is as follows. That is, it is preferable that at least a part of the pitch P12b of the dummy groove 12b is formed with a pitch P12b larger than the pitch P12a (0.74 μm is standard) of the pregroove 12a. Specifically, the pitch P12b is preferably at least twice as large as the pitch P12a of the pregroove 12a. If the pitch P12b is smaller than this, the expected effect cannot be obtained. In the present embodiment, the thickness is set to 3.0 μm, but the present invention is not limited to this and may be further increased. If the pitch P12b is excessively widened, it is difficult to form the inner peripheral edge concentrically when a recording layer to be described later is applied using, for example, a spin coating method. More preferably, all of the dummy grooves 12b are formed at a pitch P12b that is at least twice as large as the pitch P12a (0.74 μm is standard) of the pregroove 12a.
It is preferable to form all of the dummy grooves 12b with the same pitch P12b. However, the present invention is not limited to this. For example, each dummy groove 12b has a pitch larger than the pitch P12a of the pregroove 12a. It may be formed.

Next, a second embodiment of the optical information recording medium of the present invention will be described with reference to FIG. FIG. 2 is a partially enlarged cross-sectional view showing an outline of the internal structure of the optical information recording medium 20 of the second embodiment.

  As shown in FIG. 2, the optical information recording medium 20 of the present embodiment includes an optical disc main body 21 and a protective layer 25 provided on the optical disc main body 21, and a base layer 28 and an ink receiving layer are provided on the protective layer 25. It has a so-called CD-R structure in which the layer 29 is provided, and is different from the first embodiment in that a protective layer is provided instead of the adhesive layer and no dummy substrate is provided.

More specifically, the optical disc main body 21 has a hole 22c in the center, a pregroove 22a provided in the information recording area on one main surface, and a dummy provided on the inner peripheral side of the information recording area. A light transmissive substrate 22 having a groove 22b is provided. Then, a recording is provided in which a dye material is applied over a region where the pregroove 22a is formed on the main surface of the light transmissive substrate 22 and a part of the region where the dummy groove 22b is formed. The layer 23 and the dye on the inner peripheral side beyond the inner peripheral edge 23a of the recording layer 23 in the region where the dummy grooves on the recording layer 23 and the light-transmitting substrate 22 are formed. And a reflective layer 24 provided over a region where the material is not applied. The surface of the reflective layer 24 has a groove 24a reflecting the pre-groove 22a and a groove 24b reflecting the dummy groove 22b. The light-transmitting substrate 22 has a pitch P22a of the pregroove 22a in the information recording area of the light-transmitting substrate 22 in at least a part of the area where the dye material is not applied in the area where the dummy grooves 22b are formed. The dummy grooves 22b are provided with a larger pitch P22b1.

More specifically, each of the plurality of dummy grooves 22b is formed with a pitch P22b1 larger than the pitch P22a of the pre-groove 22a. The portions formed with P22b1 (3.0 μm) and the portions where the dummy grooves 22b are formed with the same pitch P22b2 as the pitch P22a (0.74 μm) of the pregroove 22a are alternately arranged.

In the present embodiment, the light-transmitting substrate 22 has a region in which the dummy groove 22b is formed at least from the position of the inner peripheral edge 24c of the reflective layer 24 to the inner peripheral side.

Next, a preferred embodiment of the protective layer 25 is as follows. That is, as the protective layer 25, a resin film made of a resin liquid mainly composed of an ultraviolet curable resin is formed by means such as a screen printing method or a spin coating method, and this is cured with ultraviolet rays to form the protective layer 25. It is preferable.
Since other configurations and operational effects are the same as those of the first embodiment, description thereof is omitted.

Next, a third embodiment of the optical information recording medium of the present invention will be described with reference to FIG. FIG. 3 is a partially enlarged sectional view showing an outline of the internal structure of the optical information recording medium 30 of the third embodiment.

  As shown in FIG. 3, the optical information recording medium 30 of this embodiment includes an optical disc body 31 and a dummy substrate 37 provided on the optical disc body 31 via an adhesive layer 36. This is the same as the first embodiment in that it has a so-called DVD-R structure in which a base layer 38 and an ink receiving layer 39 are provided.

More specifically, the optical disc main body 31 has a hole 32c in the center, a pregroove 32a provided in the information recording area on one main surface, and a dummy provided on the inner peripheral side of the information recording area. A light-transmitting substrate 32 having a groove 32b is provided. Then, a recording is provided in which a dye material is applied over a region where the pregroove 32a is formed on the main surface of the light transmissive substrate 32 and a part of the region where the dummy groove 32b is formed. Layer 33 and the recording layer 33 on the light transmissive substrate 32 in the region where the dummy groove 32b is formed, beyond the inner peripheral side edge 33a of the recording layer 33 and further on the inner peripheral side. And a reflective layer 34 provided over an uncoated region. The surface of the reflective layer 34 has a groove 34a reflecting the pre-groove 32a and a groove 34b reflecting the dummy groove 32b. The light-transmitting substrate 32 has an area where the dye material is not applied in the area where the dummy groove 32b is formed, and is deeper than the depth D32a of the pregroove 32a in the information recording area of the light-transmitting substrate 32. The dummy groove 32b is provided with a shallow depth D32b.

In the present embodiment, the light-transmitting substrate 32 has a region where the dummy groove 32b is formed at least from the position of the edge 34c on the inner peripheral side of the reflective layer 34 to the inner peripheral side.

A preferred embodiment of the depth D32b of the dummy groove 32b is as follows. That is, as the depth D32b of the dummy groove 32b, the region where the dye material is not applied in the region where the dummy groove 32b of the light transmissive substrate 32 is formed is the information recording region of the light transmissive substrate 32. The dummy groove 32b is preferably provided with a depth D32b shallower than the depth D32a of the pregroove 32a. Specifically, the depth D32b is preferably shallower than the depth D32a of the pregroove 32a. For example, when the depth D32a of the pregroove 32a is 140 nm, it is preferably smaller than this.
Since other configurations and operational effects are the same as those of the first embodiment, description thereof will be omitted.

Next, a fourth embodiment of the optical information recording medium of the present invention will be described with reference to FIG. FIG. 4 is a partially enlarged sectional view showing an outline of the internal structure of the optical information recording medium 40 of the fourth embodiment.

  As shown in FIG. 4, the optical information recording medium 40 of the present embodiment includes an optical disc main body 41 and a dummy substrate 47 provided on the optical disc main body 41 with an adhesive layer 46 interposed therebetween. Is similar to the first embodiment in that it has a so-called DVD-R structure in which a base layer 48 and an ink receiving layer 49 are provided.

More specifically, the optical disc main body 41 has a hole 42c in the center, a pregroove 42a provided in the information recording area on one main surface, and a dummy provided on the inner peripheral side of the information recording area. A light transmissive substrate 42 having a groove 42b is provided. Then, a recording is provided in which a dye material is applied over a region where the pregroove 42a is formed on the main surface of the light transmissive substrate 42 and a part of the region where the dummy groove 42b is formed. The layer 43 and the recording layer 43 on the light transmissive substrate 42 in the region where the dummy groove 42b is formed, beyond the inner peripheral side edge 43a of the recording layer 43 and further on the inner peripheral side. And a reflective layer 44 provided over a region where the dye material is not applied. The surface of the reflective layer 44 has a groove 44a reflecting the pre-groove 42a and a groove 44b reflecting the dummy groove 42b. The light-transmitting substrate 42 is larger than the half-value width W42a of the pre-groove 42a in the information recording region of the light-transmitting substrate 42 in the region where the dye material is not applied in the region where the dummy grooves 42b are formed. The dummy groove 42b is provided with a narrow half-value width W42b.

In the present embodiment, the light-transmitting substrate 42 has a region where the dummy groove 42b is formed at least from the position of the inner peripheral side edge 44c of the reflective layer 44 to the inner peripheral side.

A preferred embodiment of the half width W42b of the dummy groove 42b is as follows. That is, as the half width W42b of the dummy groove 42b, the region where the dye material is not applied in the region where the dummy groove 42b of the light transmissive substrate 42 is formed is the information recording region of the light transmissive substrate 42. The dummy groove 42b is preferably provided with a half-value width W42b narrower than the half-value width W42a of the pre-groove 42a. Specifically, the full width at half maximum W42b is preferably narrower than the full width at half maximum W42a of the pregroove 42a. For example, when the full width at half maximum W42a of the pregroove 42a is 0.35 μm, it is preferably narrower than this.
Since other configurations and operational effects are the same as those of the first embodiment, description thereof is omitted.

In the above embodiment, an optical information recording medium having a DVD-R structure and an optical information recording medium having a CD-R structure are shown. However, the present invention is not limited to this, and a DVD + R structure, an HD-DVD, and a BD. (Blu-ray Disc) It can be applied to various other optical information recording media.
In the above-described embodiment, an example of an optical information recording medium having a single recording layer as an optical disc main body has been described. However, the present invention is not limited to this, and for example, the optically transparent substrate has a plurality of layers in the thickness direction. It may be a so-called multilayer recording type optical information recording medium in which a second recording layer and a transflective layer are provided between them and a plurality of recording layers are provided.
In this case, it is preferable that the dummy groove is provided on the light transmissive substrate closest to the label surface among the plurality of light transmissive substrates provided.
Further, when a plurality of recording layers are disposed as the optical disc body as described above, for example, on the surface side of the one light transmissive substrate on which the second recording layer and the semi-transmissive reflective layer are provided, A transparent resin layer may be provided as the other light transmissive substrate, and the pregroove and the dummy groove may be transferred to the surface of the transparent resin layer with a mold or the like.

It is a partial expanded sectional view which shows the outline | summary of the internal structure of 1st Embodiment of the optical information recording medium of this invention. It is a partial expanded sectional view which shows the outline | summary of the internal structure of 2nd Embodiment of the optical information recording medium of this invention. It is a partial expanded sectional view which shows the outline | summary of the internal structure of 3rd Embodiment of the optical information recording medium of this invention. It is a partial expanded sectional view which shows the outline | summary of the internal structure of 4th Embodiment of the optical information recording medium of this invention. It is a partial expanded sectional view for explaining a subject which the present invention tends to solve.

Explanation of symbols

10: optical information recording medium 11: optical disc body 12: light transmissive substrate 12a: pre-groove 12b: dummy groove 12c: hole 13: recording layer 13a: edge 14: reflective layer 14a: groove 14b: groove 14c: edge 16 : Adhesive layer 17: Dummy substrate 18: Underlayer 19: Ink receiving layer 20: Optical information recording medium 21: Optical disc body 22: Optically transmissive substrate 22a: Pregroove 22b: Dummy groove 22c: Hole 23: Recording layer 23a: Edge 24: Reflective layer 24a: Groove 24b: Groove 24c: Edge 25: Protective layer 28: Underlayer 29: Ink receiving layer 30: Optical information recording medium 31: Optical disc body 32: Light transmissive substrate 32a: Pregroove 32b : Dummy groove 32c: Hole 33: Recording layer 33a: Edge 34: Reflective layer 34a: Groove 34b: Groove 34c: Edge 36: Adhesive layer 37: Dummy substrate 8: Underlayer 39: Ink receiving layer 40: Optical information recording medium 41: Optical disc main body 42: Light transmissive substrate 42a: Pregroove 42b: Dummy groove 42c: Hole 43: Recording layer 43a: Edge 44: Reflective layer 44a: Groove 44b: Groove 44c: Edge 46: Adhesive layer 47: Dummy substrate 48: Underlayer 49: Ink receiving layer P12a: Groove pitch P12b: Groove pitch P22a: Groove pitch P22b1: Groove pitch P22b2: Groove pitch Pitch D32a: Groove depth D32b: Groove depth W42a: Groove half width W42b: Groove half width

Claims (4)

A light-transmitting substrate having a hole in the center and having a pregroove provided in an information recording area on one main surface and a dummy groove provided on the inner peripheral side of the information recording area; and the light-transmitting substrate A recording layer provided by applying a dye material over a region of the main surface where the pregroove is formed and a part of the region where the dummy groove is formed, and on the recording layer and the light A reflective layer provided over the non-coated region of the pigment material on the transparent substrate, and a groove reflecting the pregroove and a groove reflecting the dummy groove on the surface of the reflective layer. And having
The light transmissive substrate has a pitch larger than the pre-groove pitch of the information recording region of the light transmissive substrate in at least a part of the region where the dye material is not applied in the region where the dummy grooves are formed. An optical information recording medium provided with the dummy groove. The light transmissive substrate is provided with a dummy groove at a pitch larger than the pre-groove pitch of the information recording region of the light transmissive substrate in the region where the dye material is not applied in the region where the dummy groove is formed. The optical information recording medium according to claim 1, wherein the optical information recording medium is provided. A light-transmitting substrate having a hole in the center and having a pregroove provided in an information recording area on one main surface and a dummy groove provided on the inner peripheral side of the information recording area; and the light-transmitting substrate A recording layer provided by applying a dye material over a region of the main surface where the pregroove is formed and a part of the region where the dummy groove is formed, and on the recording layer and the light A reflective layer provided over the non-coated region of the pigment material on the transparent substrate, and a groove reflecting the pregroove and a groove reflecting the dummy groove on the surface of the reflective layer. And having
In the light transmissive substrate, in the region where the dye material is not applied in the region where the dummy groove is formed, the half width of the pregroove in the information recording region of the light transmissive substrate (1/2 of the groove depth). An optical information recording medium characterized in that the dummy groove is provided with a half-value width narrower than the width of the groove at the point. The optically transparent substrate, according to any one of claims 1 to 3, characterized in that at least the said dummy grooves to the inner peripheral side than the position of the edge portion of the inner peripheral side of the reflective layer is formed regions Optical information recording medium.

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