JP2009181620A - Optical disk - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk with which a color of appearance of an image color printed on a label surface with an ink is kept constant. <P>SOLUTION: The optical disk 10 includes: a printable layer 16 which includes the label surface A color printable with the ink; and a visible ray reflection layer 15 disposed on the inside of the printable layer 16. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical disc in which the color of a label surface is stabilized.

  2. Description of the Related Art Media processing apparatuses that record electronic data such as audio and video on a large number of optical disks such as CDs and DVDs and perform label printing are known. Such a media processing apparatus includes an optical disk drive apparatus that records electronic data on a medium (optical disk) by laser light, and an inkjet printer that prints a title, a design, and the like on a label surface.

  An optical disc capable of ink-jet printing on the label surface by the media processing device or the like needs to have a printable layer capable of color printing with ink on the label surface. An optical disc provided with this printable layer is disclosed in, for example, Patent Document 1.

The visible light information medium (optical disk) disclosed in Patent Document 1 includes a protective layer that protects a recording portion on a transparent light-transmitting substrate, can record information that can be read optically by laser light, and transmits the transparent light. A hydrophilic ultraviolet curable resin film (printable layer) capable of fixing water-based printing ink is formed on the back surface of the visible light substrate on the side where the visible light is incident, and an ink jet printer is used on the surface of the printable layer. Printing is possible.
Japanese Patent Laid-Open No. 8-102088

  In the above-mentioned printer of the media processing apparatus, in order to keep the color of the image printed on the label surface of the optical disc provided with the printable layer constant, the color is measured by a colorimeter and compared with the reference color. The ink composition is controlled so as to maintain a constant and optimum color (appearance color).

  However, when measuring with the above colorimeter on an optical disc having a conventional printable layer, visible light is incident from the data recording surface of the optical disc or the side surface of the disc and passes through the label surface, so that the image is recorded. The color of the appearance changes. For this reason, the measurement result by the colorimeter becomes unstable.

  In addition, when a user holds an optical disc that has already been printed on the label, the color of the image printed on the label surface is obtained by allowing visible light to enter from the data recording surface or the side surface of the disc and pass through the label surface. Changes, and there is a problem that it looks different from the color intended by the disc creator.

  An object of the present invention is to solve the above-described problems, and to provide an optical disc capable of maintaining a constant color appearance of an image colored and printed with ink on a label surface.

An optical disc according to the present invention capable of solving the above-mentioned problems is an optical disc on which data that can be optically read by a laser beam can be reproduced and / or recorded.
The back surface of the data recording surface on which the laser beam is incident is a label surface,
A printable layer that forms the label surface and is printable with ink on the label surface;
And at least a visible light reflection layer provided inside the printable layer.
According to the above configuration, the visible light incident from the label surface and passing through the printable layer is reflected by the visible light reflection layer, and is emitted to the label surface side through the printable layer. Further, the visible light reflecting layer restricts visible light incident from the data recording surface side from being transmitted to the printable layer.
As a result, only visible light from the label surface side acts on the label surface, so that the visible light incident from the data recording surface changes depending on the environment in which the optical disk is placed, and the image colored and printed with ink on the label surface Since the appearance color can be prevented from changing, the color of the image can be kept constant.

The visible light reflection layer is preferably formed adjacent to the inside of the printable layer.
According to the above configuration, the visible light reflection layer adjacent to the printable layer reflects the visible light incident from the label surface and passing through the printable layer directly under the printable layer, and is also incident from the data recording surface side. Is controlled directly below the printable layer. Therefore, since there is no other layer between the printable layer and the visible light reflecting layer, there is no visible light incident from the edge of the layer between the printable layer and the visible light reflecting layer, and the above-mentioned is more reliably performed. The color of the image can be kept constant.

The visible light reflection layer is preferably formed through a protective layer for protecting the optical disk.
According to the above configuration, since the protective layer is formed immediately below the printable layer, the visible light reflecting layer can be efficiently protected against physical or mechanical obstacles received from the label surface side.

Further, the optical disc includes a clamping region from the clamp hole to the inner periphery of the label printable region on the label surface side, and a transparent disc edge extending from the outer periphery of the label printable region to the outer periphery of the optical disc. Have
The visible light reflecting layer is formed to cover a side surface of the inner edge portion of the printable layer adjacent to the clamping region and a side surface of the outer edge portion of the printable layer adjacent to the disk edge portion. It is preferable.
According to the above configuration, the visible light is prevented from entering the printable layer from the outside through the side surface of the edge portion of the printable layer, and the visible light is also prevented from leaking to the outside from the side surface of the edge portion. be able to. Therefore, the effect of preventing the change in the appearance color of the image printed on the printable layer can be further enhanced.

  The material of the visible light reflecting layer is preferably magnesium oxide or barium sulfate. By forming using such a material, a visible light reflective layer having a high reflectance can be formed.

Embodiments of an optical disc according to the present invention will be described below with reference to the drawings.
FIG. 1 is a plan view of an optical disc according to an embodiment of the present invention as viewed from the label surface side.

  As shown in FIG. 1, the optical disk according to the present embodiment is a disk-shaped optical disk 10 such as a CD or DVD that can be printed with ink on a label surface A on which a title, a design, and the like are printed. As will be described later, the optical disc 10 includes at least a printable layer 16 that can be printed on the label surface A with ink, and a visible light reflection layer 15 provided inside the printable layer 16 (FIGS. 2 to 2). 4). Note that printing on the label surface A can be performed by a media processing device, a single inkjet printer, or the like.

  In FIG. 1, a hole provided in the center of an optical disk 10 is a clamp hole 19 for clamping with a clamper of a spindle of an optical disk drive device. The periphery of the clamp hole 19 is a clamp formed only by a transparent substrate 11. It is a ping area 20.

  Further, the label surface A side outside the clamping area 20 is a printable area 21. The disk edge 22 on the outer periphery of the printable area 21 is an area formed by the transparent substrate 11, as in the clamping area 20.

  Hereinafter, a cross-sectional structure of an optical disc according to an embodiment of the present invention will be described in detail with reference to Examples 1 to 3.

FIG. 2 is a cross-sectional view showing the structure of Example 1 of the optical disc according to the embodiment of the present invention.
The optical disc 10A according to the first embodiment is, for example, an optical disc such as a CD having a single recording layer, and the cross-sectional structure in the printable area 21 is a single side of the transparent substrate 11 (see FIG. 2). In this structure, the data data recording layer 12, the laser reflecting layer 13, the protective layer 14, the visible light reflecting layer 15, and the printable layer 16 are sequentially stacked on the upper surface in FIG.

  The transparent substrate 11 is made of polycarbonate, polymethyl methacrylate, epoxy resin or the like. The data recording layer 12 uses an organic dye material to form pits by utilizing a chemical change that is the decomposition of the dye by laser light irradiation, or uses a metal material to change the phase of the metal material by heating by laser light irradiation (crystallization).・ Data is recorded by changing the reflectance by non-crystallization.

  For example, aluminum or an aluminum alloy is used for the laser reflection layer 13. The protective layer 14 is a layer that protects the data recording layer 12 that records data against physical or mechanical failure received from the label surface A side, and is formed of an ultraviolet curable resin or the like having excellent impact resistance. In addition, the entire optical disc is prevented from warping and the strength is improved. The protective layer 14 may be a layer formed by laminating a plurality of layers made of different materials.

  The visible light reflecting layer 15 is made of a magnesium oxide or barium sulfate film, and reflects visible light incident through the printable layer 16 from the label surface A toward the label surface A side with a high reflectance in the direction of the arrow in FIG. To function.

  The printable layer 16 is made of an ultraviolet curable resin film or the like, and the surface of the printable layer 16 becomes a printable region 21. The printable area 21 is an area in which an image can be printed by ejecting ink from an inkjet printer or the like, and a title, a design, and the like can be printed on the label surface A.

  The back surface of the label surface A of the optical disc 10 (10A) is a data recording surface B on which data is recorded (or data is read), and laser light is transmitted from the data recording surface B to the data recording layer 12 through the transparent substrate 11. By irradiating, it is possible to record the data by changing it into a pit row or a phase change, or to read out the data recorded in the data recording layer 12 from the reflected visible light of the irradiated laser beam. At this time, the laser reflection layer 13 increases the absorption rate of the laser beam in the data recording layer 12 during data recording, or increases the reflectance of the laser beam during data reading.

  In the first embodiment, as described above, the visible light reflecting layer 15 is provided immediately below the printable layer 16, so that visible light that has passed through the printable layer 16 from the label surface A and entered is visible light. Reflected by the reflective layer 15 toward the label surface A side with a high reflectance.

  Also, visible light that enters the disk 10A from the opposite data recording surface B or side surface is reflected to the data recording surface B side, and therefore hardly transmits to the printable layer 16. Thereby, it is possible to prevent the appearance color of the image printed on the printable layer 16 from being changed by visible light incident from the data recording surface B or the side surface of the disk.

  FIG. 3 is a cross-sectional view showing the structure of Example 2 of the optical disc according to the embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the component same as Example 1 shown in FIG. 2, and the duplication description is abbreviate | omitted.

  As shown in the cross-sectional view of FIG. 2, the cross-sectional structure of the optical disc 10 </ b> B according to the second embodiment is as follows. In this structure, the light reflecting layer 15, the protective layer 14, and the printable layer 16 are sequentially stacked.

  In Example 2, the structure is the same as in Example 1 except that the protective layer 14 is formed between the visible light reflecting layer 15 and the printable layer 16.

Also in the second embodiment, visible light incident from the printable layer 16 can be reflected by the visible light reflection layer 15 toward the printable layer 16 with a high reflectance. Therefore, also in this case, it is possible to prevent the appearance color of the image printed on the printable layer 16 from being changed by visible light incident from the data recording surface B or the side surface of the disc.
Further, since the protective layer is formed immediately below the printable layer, the visible light reflecting layer can be efficiently protected against physical or mechanical obstacles received from the label surface side.

  FIG. 4 is a cross-sectional view showing the structure of Example 3 of the optical disc according to the embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the component same as Example 1 shown in FIG. 2, and the duplication description is abbreviate | omitted.

  The cross-sectional structure in the printable area 21 of the optical disc 10C according to the third embodiment is such that the data recording layer 12, the laser reflective layer 13, the protective layer 14, the visible light reflective layer 15, and the printable are formed on one side (upper surface in FIG. 4) of the transparent substrate 11. In this structure, the layers 16 are sequentially stacked.

  Then, at the inner edge 21A and the outer edge 21B of the label printable area 21, as shown in FIG. 4, the visible light reflecting layer 15 is formed up to the surface of the label surface A of the optical disk 10C, and the edge of the printable layer 16 is formed. It is formed so as to cover the side surfaces of the edge of the printable layer 16 on the clamping region 20 side and the edge of the printable layer 16 on the disk edge 22 side.

  In addition to the same effects as in the first embodiment, this structure further prevents visible light from being incident on the printable layer 16 from the outside through the side surface of the edge portion of the printable layer 16, and the edge of the printable layer 16. It is also possible to prevent the visible light from leaking out from the side surface of the part. Accordingly, it is possible to further increase the effect of preventing the appearance color of the image printed on the printable layer 16 from changing.

  The laminated structure of the optical disks 10A, 10B, and 10C in Examples 1 to 3 has been described by taking the structure of an optical disk such as a CD having a single recording layer as an example, but the label surface, which is a feature of the present invention, is described. As long as A includes the printable layer 16 that can be printed with ink and the visible light reflection layer 15 provided inside the printable layer 16, another layered structure may be used. For example, it may be an optical disc having a multilayer structure having two or more recording layers, and can be applied to optical discs of various standards such as write-once type and repetitive recording type in DVDs, next-generation optical discs and the like.

As described above, the optical disc 10 (10A, 10B, 10C) according to the embodiment of the present invention has the printable layer 16 that can be colored and printed on the label surface A with ink, and the visible layer provided inside the printable layer 16. By providing the light reflecting layer 15, visible light that is incident from the label surface A and passes through the printable layer 16 is reflected by the visible light reflecting layer 15, and is emitted to the label surface A side through the printable layer 16. The visible light reflection layer 15 restricts transmission of visible light incident from the data recording surface B side to the printable layer 16.
Thereby, only visible light from the label surface A side acts on the label surface A. Therefore, the visible light incident from the data recording surface B changes depending on the environment where the optical disc 10 (10A, 10B, 10C) is placed, Since it is possible to prevent the appearance color of an image colored and printed with ink on the label surface A from changing, the color of the image can be kept constant.

It is a top view which shows the optical disk which concerns on embodiment of this invention. It is sectional drawing which shows the structure of Example 1 of the optical disk based on embodiment of this invention. It is sectional drawing which shows the structure of Example 2 of the optical disk which concerns on embodiment of this invention. It is sectional drawing which shows the structure of Example 3 of the optical disk which concerns on embodiment of this invention.

Explanation of symbols

  10 (10A, 10B, 10C) ... optical disc, 11 ... transparent substrate, 12 ... data recording layer, 13 ... laser reflecting layer, 14 ... protective layer, 15 ... visible light reflecting layer, 16 ... printable layer, 19 ... clamp hole, DESCRIPTION OF SYMBOLS 20 ... Clamping area, 21 ... Printable area, 21A ... Inner edge (of label printable area 21), 21B ... Outer edge (of label printable area 21), 22 ... Disc edge, A ... Label surface , B ... Data recording surface

Claims (5)

An optical disc capable of reproducing and / or recording data optically readable by a laser beam,
The back surface of the data recording surface on which the laser beam is incident is a label surface,
A printable layer that forms the label surface and is printable with ink on the label surface;
An optical disc comprising at least a visible light reflection layer provided inside the printable layer.   2. The optical disc according to claim 1, wherein the visible light reflection layer is formed adjacent to the inside of the printable layer.   The optical disk according to claim 1, wherein the visible light reflection layer is formed through a protective layer for protecting the optical disk. The optical disk has a clamping area from the clamp hole to the inner periphery of the label printable area on the label surface side, and a transparent disk edge extending from the outer periphery of the label printable area to the outer periphery of the optical disk. ,
The visible light reflecting layer is formed to cover a side surface of the inner edge portion of the printable layer adjacent to the clamping region and a side surface of the outer edge portion of the printable layer adjacent to the disk edge portion. The optical disc according to any one of claims 1 to 3, wherein   The optical disk according to any one of claims 1 to 4, wherein a material of the visible light reflection layer is magnesium oxide or barium sulfate.

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