JP2000132866A - optical disk - Google Patents

Abstract

(57) Abstract: A cover sheet is not accidentally peeled off an optical disk without a part of the cover sheet protruding from an outer peripheral edge of the optical disk, and the cover sheet is intentionally peeled from the optical disk. In some cases, the cover sheet 26 can be easily peeled off from the optical disc. SOLUTION: An optical disc is capable of recording a signal by irradiating recording light from a light transmitting substrate 21 side. A cover sheet 26 is provided releasably on the recording light and reproduction light incident surfaces of the translucent substrate 21, and tabs 27 project from the outer peripheral edge of the cover sheet 26. As a part 28 of the outer peripheral edge, it is flush with the peripheral surface of the light transmitting substrate 21. Cover sheet 2
The other part of the outer peripheral edge except for the part 28 of the outer peripheral edge of No. 6 is inside the outer peripheral edge of the light transmitting substrate 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk on which signals can be recorded by irradiating recording light from the light-transmitting substrate side. The present invention relates to an attached optical disk.

[0002]

2. Description of the Related Art A compact disk (CD), which has been used as a medium for music, and a CD-ROM, which has been used as a medium for a computer, have been used.
Commercially available optical disks are read-only. Such a read-only optical disk usually uses a mold obtained through a process such as electroforming or pressing when forming a light-transmitting substrate made of polycarbonate or the like, and is formed on the surface of the light-transmitting substrate. Signals are recorded by forming uneven pits. With such an optical disc, a user cannot record information by himself.

On the other hand, since the end of the 1980s, 199
Toward the beginning of the year, a recordable so-called write-once CD (CD-R) compatible with the CD has been developed. This CD-R is usually shipped without recording a signal, and can record arbitrary information desired by the user only once. This allows the user to copy a CD or CD-ROM on which arbitrary information is recorded while having compatibility with a CD or CD-ROM at a relatively low cost.

A CD-R generally has a dye recording layer such as a cyanine dye formed on a plate-shaped translucent substrate made of a transparent synthetic resin such as polycarbonate, and a metal film such as an Au film formed thereon. A reflective layer is applied, and a protective layer made of an ultraviolet curable resin is further formed thereon. On the side of the porous substrate on which the dye recording layer is formed, for example,
A spiral tracking guide having a pitch of 1.6 μm is provided.

When a signal is recorded on the CD-R, pulse-modulated recording is performed while tracking the spot of the recording light emitted from the optical pickup through the translucent substrate onto the dye recording layer along a tracking guide. The dye recording layer is irradiated with a light spot, and a pulse signal is written as a pit. At this time, the dye recording layer is heated in response to the pulse signal, is melted, and the dye material of the dye recording layer that has been partially decomposed and the resin material of the translucent substrate that is heated and dissolved interact with each other, Pits are formed on the porous substrate. Thus, desired information from which a signal similar to that of a CD or a CD-ROM can be read is written.

[0006] This CD-R is a read-only CD or CD-R.
An optical disk on which information completely compatible with a CD or CD-ROM can be easily obtained in a desktop environment without going through a large-scale manufacturing facility or a complicated manufacturing process used in a ROM manufacturing process. Since the light-transmitting substrate of an optical disk is made of a resin such as polycarbonate, static electricity is generated and dust easily adheres to the light incident surface of the surface. easy. As described above, dust and scratches on the light incident surface of the translucent substrate impede the incidence of laser light, and significantly degrade writing characteristics.

In order to solve the above problem, in a conventional optical disk, a releasable cover sheet is attached to a surface of a light-transmitting substrate, which is a recording light and reproducing light incident surface, to protect the surface of the light-transmitting substrate. That is being done. For example, in the case where a transparent cover sheet is attached, recording and reproduction can be performed with the cover sheet attached to the surface of the light-transmitting substrate. On the other hand, when a colored sheet or an opaque cover sheet having an effect of blocking light in the photosensitive wavelength band of the dye recording layer is attached, there is also an effect of preventing deterioration of the dye recording layer due to natural light or the like. Further, when the cover sheet contains an antistatic agent, the adhesion of dust due to static electricity can be prevented. As described above, by attaching the cover sheet to the surface of the translucent substrate of a recordable optical disc such as a CD-R, there are various advantages.

FIGS. 4 and 5 show a state in which a cover sheet 6 is attached to the light incident surface of the light transmitting substrate 1 of the optical disk. The conventional cover sheet 6 has the same planar shape as the translucent substrate 1, and the cover sheet 6 is attached to the light incident surface of the translucent substrate 1 with an adhesive. The cover sheet 6 is affixed over the entire surface of the translucent substrate 1. Therefore, the outer peripheral edge of the cover sheet 6 and the translucent substrate 1 and the inner peripheral edge on the side of the clamp hole 5 are all flush. I have. The cover sheet 6 has a tab 7 protruding from the outer peripheral edge of the cover sheet 6 to peel it off from the translucent substrate 1, and the tab 7 protrudes from the outer periphery of the translucent substrate 1. As shown in FIG. 5, when the cover sheet 6 attached to the light-transmitting substrate 1 is peeled off from the light-transmitting substrate 1, the tab 7 is picked up with a finger, and
As shown by, it is raised from the light-transmitting substrate 1 and peeled off.

[0009]

However, in the case of an optical disk to which the cover sheet 6 is attached as described above, the cover sheet 6 often comes off the light-transmitting substrate 1 unexpectedly during handling. The cover sheet 6 is formed such that the adhesive does not remain on the light incident surface of the translucent substrate 1 after being peeled off.
It is adhered to the light incident surface of the translucent substrate 1 with an adhesive having a somewhat low adhesive strength, and once separated, it is difficult to correctly adhere again.

Further, in the conventional cover sheet 6,
As described above, since the tab 7 protrudes from the outer peripheral edge of the light-transmitting substrate 1 in a state of being attached to the light-transmitting substrate 1, for example, when housed in a general optical disk case as shown in FIG. In some cases, the tab 7 may be sandwiched between the optical disk holder 13 and the lid 12. In FIG. 6, 11
Is a case main body, 13 is an optical disk holding portion fitted into the case main body 11, 14 is a concave portion formed in the optical disk holding portion 13 for storing an optical disk, and 16 is a clamp hole 5 of an optical disk to be stored in the concave portion 14. Of projections, 12 is a lid, 18 is this lid 12
It is a decorative sheet that is used by being inserted into a sheet.

Some optical discs can be printed on a resin-coated surface opposite to the light incident surface by using an ink jet printer. At the time of printing, the optical disk is mounted on the transport tray and sent. If the tab 7 of the cover sheet 6 protrudes from the outer peripheral edge of the translucent substrate 1 at that time, the optical disk is mounted on the transport tray. Can not do it.

The present invention has been made in view of the above-mentioned problems in a conventional optical disc having a cover sheet, and a part of the cover sheet does not protrude from an outer peripheral edge of the optical disc.
An object of the present invention is to provide an optical disc with a cover sheet that can be easily peeled off from the optical disc when the cover sheet is not accidentally peeled off from the optical disc and when the cover sheet is intentionally peeled off from the optical disc. Things.

[0013]

In order to achieve the above-mentioned object, according to the present invention, the cover sheet 26 is made to have a light-transmitting property so that all portions of the outer periphery of the cover sheet 26 do not protrude from the outer periphery of the optical disk. In order to prevent the cover sheet 26 from being accidentally peeled off while being attached to the substrate 21, other portions of the outer periphery of the sheet 26 except for a part 28 of the outer periphery of the cover sheet 26 are outside the translucent substrate 21. It was located inside the periphery. When the cover sheet 26 is intentionally peeled off, a part 28 of the outer peripheral edge of the cover sheet 26 is removed.
In order to easily cause the light from the light incident surface of the light transmitting substrate 1, only a part 28 of the outer edge of the cover sheet 26 is flush with the outer edge of the light transmitting substrate 1.

That is, the optical disk according to the present invention can read or record a signal by irradiating recording light from the light transmitting substrate 21 side. Cover sheet 26 on the entrance surface of
Is provided so as to be peelable, and a part 28 of the outer peripheral edge of the cover sheet 26 is flush with the outer peripheral edge of the translucent substrate 21, and the outer peripheral edge excluding the part 28 of the outer peripheral edge of the cover sheet 26 is provided. Is located inside the outer peripheral edge of the light-transmitting substrate 21.

More specifically, for example, the cover sheet 26
A tab 27 protrudes from the outer peripheral edge of the cover sheet 26, and the outer edge of the tab 27 is flush with the peripheral surface of the light-transmitting substrate 21 as a part 28 of the outer peripheral edge of the cover sheet 26. Alternatively, the cover sheet 26 is formed of a circular sheet smaller than the diameter of the light-transmitting substrate 21, and the cover sheet 26 is eccentrically attached to the light-transmitting substrate 21, so that the outer peripheral edge of the cover sheet 26 is formed. Is flush with the peripheral surface of the light-transmitting substrate 21.

In an optical disk having such a cover sheet 26 adhered to the light incident surface of the translucent substrate 21, not only the tab does not protrude from the outer peripheral edge of the translucent substrate 21, but also
Except for a part 28 of the outer peripheral edge of the cover sheet 26, the outer peripheral edge of the sheet 26 is inside the outer peripheral edge of the translucent substrate 21, so the tab is accidentally hooked and the cover sheet 26 is accidentally peeled off. There is no such thing. Further, it can be housed in a general optical disk case or mounted on a transport tray when printing is performed on the surface of the protective coat of the optical disk by an inkjet printer.

On the other hand, when the cover sheet 26 is intentionally peeled off from the light incident surface of the translucent substrate 21 for recording on an optical disk or the like, a part 28 of the outer peripheral edge of the cover sheet 26 is For example, a finger is applied to this portion of the translucent substrate 21 and the cover sheet 26 and the cover sheet 26 is moved from the translucent substrate 21 with the finger.
By rubbing to the side, the part 28 of the outer peripheral edge of the cover sheet 26 can be easily raised. Thereby, the cover sheet 26 can be easily peeled off from the light incident surface of the translucent substrate 21.

In the case of the most general recordable optical disc such as a CD-R, a portion 1.5 mm from the outer peripheral side is outside the recording area. Therefore, it is preferable that the outer peripheral edge of the cover sheet 26 be located inside the outer peripheral edge of the translucent substrate 21 by a dimension less than 1.5 mm, which is the maximum outside the recording area. As a result, the cover sheet 26 can cover the entire recording area on the light incident surface of the translucent substrate 21.

[0019]

Embodiments of the present invention will now be described specifically and in detail with reference to the drawings.
As the translucent substrate 21 of the optical disk shown in FIG. 1, a transparent synthetic resin plate such as a disc-shaped polycarbonate substrate formed by an injection molding method is used. The translucent substrate 21 has, for example, a thickness of 1.2 mm, an outer diameter of 120 mmφ, and an inner diameter of 15 m.
It is a donut-shaped disk of about mφ. A hole having a diameter of 15 mm at the center of the translucent substrate 21 is used for recording an optical disc,
In the reproducing device, the clamping hole 25 is used to align the optical disc with a spindle for rotating the optical disc. 26mmφ ~ 33 outside this clamping hole 25
The area of mmφ is a clamping area for clamping by the spindle for rotating the optical disk.

A tracking guide is provided on one surface of the translucent substrate 21. For example, a range of 46 to 117 mmφ in diameter on one surface of the light-transmitting substrate 21 is a signal recording area.
It has a spiral pregroove of 8 μm and a pitch of 1.6 μm. For example, a cyanine dye or the like is dissolved in an organic solvent, and the solution is spin-coated or the like, and the diameter of the translucent substrate 21 on the side having the pregroove is 45 to 118.
A dye recording layer film is formed by applying a coating having a thickness of about 130 nm to a region of mmφ and curing the coating. For example, 0.6
5 g of 1,1, dibutyl 3,3,3'3'tetramethyl 4,5,4'5'dibenzoindodicarbocyanine perchlorate (product number NK3219, manufactured by Nippon Kogaku Dyestuffs Co., Ltd.)
Is dissolved in 10 ml of a diacid alcohol solvent, and this is applied to the surface of the translucent substrate 21 by a spin coating method to form a dye recording film having a thickness of 130 nm.

Next, the diameter of this disk is 45 to 118 m.
For example, a film thickness of 7
An Au film having a thickness of 0 nm is formed, and a reflection film is formed. On this reflective film, for example, spin-coated with an ultraviolet curing resin,
This is irradiated with ultraviolet rays and cured to form a protective coat having a thickness of about 10 μm. Further, a cover sheet 26 made of thin polypropylene or the like having an adhesive applied to one side is prepared, and this adhesive surface is provided on the light-transmitting substrate 21 of the optical disk.
To the light incident surface of The illustrated cover sheet 26 is
At the center thereof, there is a hole 25 ′ having the same diameter corresponding to the clamp hole 25 of the light transmitting substrate 21, but the outer diameter of the cover sheet 26 is smaller than the outer shape of the light transmitting substrate 21. Therefore, when the cover sheet 26 is adhered to the light incident surface of the translucent substrate 21 so that the clamp holes 25 and the holes 25 ′ are aligned, the outer peripheral edge of the cover sheet 26 is more inward than the outer peripheral edge of the translucent substrate 21. Will be located.

A lip-shaped tab 27 integrally projects outward from one of the outer peripheral edges of the cover sheet 26, and the outer peripheral edge of the tab 27 is flush with the outer peripheral edge of the light-transmitting substrate 21. That is, part 2 of the outer peripheral edge of the cover sheet 26
Only the outer peripheral edge of the tab 27, which is 8, is flush with the outer peripheral edge of the translucent substrate 21. FIG. 1A shows the cover sheet 26.
Is attached to the light incident surface of the translucent substrate 21,
FIG. 2B shows a state in which the cover sheet 26 has been peeled off from the light incident surface of the translucent substrate 21. In FIG. 1 (b), the two-dot chain line indicates the position where the cover sheet 26 is stuck.

FIGS. 2A and 2B show the cover sheet 26.
The outer peripheral edge of the tab 27, which is a part 28 of the outer peripheral edge, and the outer peripheral edge of the translucent substrate 21 are flush with each other. FIG.
As shown in (a), a finger 30 is applied to a portion where the outer peripheral edge of the translucent substrate 21 and a part 28 of the outer peripheral edge of the cover sheet 26 are flush with each other. To the cover sheet 26 side. Thereby, as shown in FIG. 2B, a part 28 of the outer peripheral edge of the cover sheet 26 can be easily raised, and the cover sheet 26 can be easily peeled from the light incident surface of the translucent substrate 21 therefrom. be able to.

On the other hand, FIG. 2C shows a portion where the outer peripheral edge of the cover sheet 26 is inside the outer peripheral edge of the translucent substrate 21. In this part, the finger 30 is placed on the outer peripheral edge of the translucent substrate 21.
, The finger 30 does not hit the outer peripheral edge of the cover sheet 26, so that the cover sheet 26 is not raised. This prevents the cover sheet 26 from being accidentally peeled off. The same applies to an object other than the finger 30 that hits the outer peripheral edge of the translucent substrate 21.

For example, in the case of an optical disk having the above dimensions, a portion 1.5 mm from the outer peripheral side is outside the recording area. Therefore, the outer peripheral edge of the cover sheet 26 is positioned inside the outer peripheral edge of the translucent substrate 21 by a dimension less than 1.5 mm, which is the maximum outside the recording area. Thus, the cover sheet 26 covers the entire recording area on the light incident surface of the translucent substrate 21. However, in view of a certain level of safety, it is preferable that the outer peripheral edge of the cover sheet 26 be located at most about 0.5 mm inside the outer peripheral edge of the translucent substrate 21. The outer peripheral edge of the cover sheet 26 is the translucent substrate 2
If it is about 0.5 mm inside from the outer peripheral edge of No. 1, FIG.
When the finger 30 touches the outer circumference of the optical disk with the finger 30, the finger 30 does not touch the outer edge of the cover sheet 26 as shown in FIG.

FIG. 3 shows another embodiment of the optical disk having the cover sheet 26 according to the present invention. FIG.
(A), tabs 27, 27 are projected from two places 180 ° apart from each other on cover sheet 26, and cover sheet 26 is projected.
The outer peripheral edges of the tabs 27, 27, which are part 28 of the outer peripheral edge, are flush with the outer peripheral edge of the translucent substrate 21.
Other portions of the outer periphery of the cover sheet 26 except for the outer periphery of the tabs 27, 27 are inside the outer periphery of the light-transmitting substrate 21.

FIG. 3B shows a clamp hole 2 having an outer diameter smaller than the outer diameter of the translucent substrate 21 and having a smaller diameter.
A cover sheet 26 having a hole 25 'having the same diameter as the hole 5 and having the hole 25' and the outer peripheral edge eccentric is used. The cover sheet 26 is attached to the light incident surface of the light transmitting substrate 21 in a state where the holes 25 ′ of the cover sheet 26 and the clamp holes 25 of the light transmitting substrate 21 are aligned with each other. In this optical disc, the outer peripheral edge of the cover sheet 26 is eccentric with respect to the outer peripheral edge of the translucent substrate 21. Thereby, a part 28 of the outer peripheral edge of the cover sheet 26 is flush with the outer peripheral edge of the translucent substrate 21, and
The other portion of the outer peripheral edge is inside the outer peripheral edge of the translucent substrate 21.

Also in this optical disk, the transparent substrate 2
The outer peripheral edge of the cover sheet 26 is flush with the part 28 of the outer peripheral edge of the cover sheet 26, and the cover sheet 26 is easily placed.
Can be raised. Thereby, the cover sheet 26 can be easily peeled off from the light incident surface of the translucent substrate 21.

On the other hand, even if a finger or the like touches the outer peripheral edge of the translucent substrate 21, the outer peripheral edge of the cover sheet 26 does not touch the outer peripheral edge of the cover sheet 26. 26 does not occur. by this,
The cover sheet 26 does not come off unexpectedly.
Although the above-described example describes an optical disc on which a signal can be recorded by irradiating recording light, the present invention is similarly applicable to an optical disc on which a signal is recorded in advance, such as a CD or a CD-ROM. Needless to say.

[0030]

As described above, the cover sheet 26 does not protrude from the optical disc without part of the cover sheet 26 protruding from the outer peripheral edge of the optical disc, and the cover sheet 26 is intentionally removed from the optical disc. When peeling, the cover sheet 26 can be easily peeled off the optical disk by easily raising a part of the outer peripheral edge of the cover sheet. Further, even an optical disk having a cover sheet attached thereto can be stored in a commercially available case, or can be mounted on a transport tray when printing on the surface of the protective coat using an inkjet printer.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an optical disc according to an embodiment of the present invention, with a cover sheet adhered to and detached from the optical disc.

FIG. 2 is a main part side view showing a state in which a finger is placed on a cover sheet of the optical disc and an outer peripheral portion of the optical disc;

FIG. 3 is a plan view showing an optical disc according to another embodiment of the present invention, with a cover sheet attached to the optical disc.

FIG. 4 is a perspective view showing a conventional example of an optical disc when a cover sheet is peeled off from the optical disc.

FIG. 5 is a perspective view showing a conventional example of an optical disk in which a cover sheet is stuck to the optical disk.

FIG. 6 is an exploded perspective view showing an optical disk having a cover sheet attached thereto and an optical disk case.

[Explanation of symbols]

 Reference Signs List 21 translucent substrate 25 clamp hole 26 cover sheet 27 tab 28 part of outer peripheral edge of cover sheet

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Ariake Shin 6-16-20 Ueno, Taito-ku, Tokyo Taiyo Denki Co., Ltd. F-term (reference) 5D029 LB02 LB05 PA10

Claims (4)

[Claims] An optical disc capable of reading or recording a signal by irradiating recording light from a light transmitting substrate (21) side to a recording light and reproducing light incident surface of the light transmitting substrate (21). A cover sheet (26) is provided so as to be peelable, and a part (2) of an outer peripheral edge of the cover sheet (26) is provided.
8) is flush with the outer periphery of the translucent substrate (21), and a part (28) of the outer periphery of the cover sheet (26).
An optical disk characterized in that another portion of the outer peripheral edge except for (1) is inside the outer peripheral edge of the translucent substrate (21). 2. A tab (27) protrudes from an outer peripheral edge of the cover sheet (26), and an outer edge of the tab (27) serves as a part (28) of an outer peripheral edge of the cover sheet (26). 2. The optical disk according to claim 1, wherein the optical disk is flush with the peripheral surface of (21). The cover sheet (26) is made of a light-transmitting substrate (2).
The cover sheet (26) is formed of a circular sheet smaller than the diameter of 1), and is eccentrically attached to the light-transmitting substrate (21).
The optical disk according to claim 2, wherein a part (28) of an outer peripheral edge of the optical disk is flush with a peripheral surface of the light-transmitting substrate (21). 4. The outer peripheral edge of the cover sheet (26) is located inside the outer peripheral edge of the translucent substrate (21) by a dimension less than 1.5 mm at the maximum. An optical disc according to any one of claims 1 to 3.