JPH06103587B2 - optical disk - Google Patents

Description

TECHNICAL FIELD The present invention relates to an optical disc as an information recording carrier suitable for, for example, a PCM audio disc, and more specifically, to display information related to recorded information on a disc surface. The present invention relates to an improved optical disc.

[Prior Art] The structure of an optical disc as an information recording carrier suitable for the above-mentioned PCM audio disc, etc. is such that a digitized signal is formed on one side (signal recording side) of a transparent resin substrate by minute dents called pits. Recording is performed, the surface of the recording surface is covered with a reflective film, and a signal is optically recorded / reproduced by a laser beam incident from the other surface (signal reading surface) of the substrate.

If the recorded content of the disc is printed on a label made of paper and attached to the center of the disc as in the case of an analog record on such an optical disc, the disc may be deformed due to moisture absorption and drying of the label. Further, in the case of a disc having a small diameter, it is necessary to make a label which is considerably small in order to be attached to the center portion of the disc, which makes it difficult to visually display the recorded contents.
Further, it is not possible to display the information related to the recorded information on the surface of such an optical disc, for example, in Japanese Utility Model Publication 57-49.
The prior art disclosed in Japanese Patent No. 733 is known. In this prior art, information contents are recorded by pits on one surface of a resin substrate that becomes the disc body, and a pattern, characters, etc. for displaying the recorded contents are printed on the surface on a reflective film that covers the surface of the pit recording surface, A thin film coated with an adhesive is attached to the back surface, and the protective film function and the display label effect are achieved with this film.

A printing technique for displaying and printing the above-mentioned recorded contents on the surface of a plastic sheet of an analog record has been disclosed in, for example, Japanese Utility Model Publication Nos. 49-142201, 49-38769 and 37-22106. Prior art is known. Among these prior arts, JP-A-49-142201 and JP-A-49-38769 disclose an indication of recorded content on the other surface of a plastic sheet having a recording sound groove formed on one surface. In this case, the layer adhered to the surface of the sheet is subjected to a paper-making process suitable for printing, and then characters, figures and other printing are applied thereto. Also,
Japanese Utility Model Publication No. 37-22106 has a display section in which the music, lyrics, singer name, etc. are directly printed on the surface of the central non-sound groove portion of a record having a sound groove formed.

By the way, as in the prior art disclosed in Japanese Utility Model Laid-Open No. 57-49733, a thin film on which a pattern, characters, etc., which are related to the recorded contents, is printed on the front surface, through an adhesive layer applied on the back surface thereof. With the format of sticking on the reflective film on the recording surface, similar to the problem that occurs with the paper label sticking method used in the conventional analog record creation, when sticking the film, there is a mistake in sticking, misalignment, Problems such as wrinkles occur. In addition, as a problem that occurs after attachment, problems such as shrinkage and peeling of the film also occur due to changes in moisture, temperature, etc. derived from the interposition of the adhesive layer. Further, since an adhesive is used, if the coating thickness of the adhesive layer applied to the back surface of the film is uneven, the weight balance of the entire disc becomes uneven, and the disc having high-density information is used as a reproducing device. There was also a serious problem in that when the disc was set and played back at high speed, the disc wobbled and the correct playback was impaired.

In addition, Japanese Utility Model Publication No. S49-142201 and Japanese Utility Model Publication No. S49-38769.
In the prior art disclosed in Japanese Patent Laid-Open Publication No. JP-A No. 2004-242242, on the surface of a plastic sheet that serves as a substrate for a record, a layer having a paper-like property applied to the board is printed with an indication of information related to the record information, Unlike the prior art disclosed in Japanese Utility Model Application Laid-Open No. 57-49733, problems such as incorrect film (label) sticking and misalignment do not occur, but the layer to be printed is preliminarily made suitable for printing. When the prior art is applied to the display printing of an optical disc, the number of production steps increases and the disc production process becomes complicated. Further, the layer to be printed has a property different from that of the plastic sheet board surface serving as the substrate by the paper-making process.Therefore, due to the difference in the properties, the change in humidity, temperature, etc. occurs between the two polymerized layers. As a result, the expansion and contraction between them changes, which causes a problem such as a peeling phenomenon or change of the printed layer. further,
As a serious problem, the reason why the layer thickness of the layer deposited on the surface of the plastic sheet becomes non-uniform during the paper-making process is generated, which causes the weight of the entire disc to be the same as the above-mentioned prior art. There is also a problem in that the balance becomes non-uniform, and the disc causes surface wobbling during reproduction, which causes a problem in correct reproduction.

Further, in the prior art disclosed in Japanese Utility Model Publication No. 37-22106, since the display of the information related to the recording information is directly printed on the surface of the central non-sound groove portion of the record having the sound groove formed, Japanese Laid-Open Publication No. 142201 and Japanese Laid-Open Publication No. 49-
Unlike the prior art disclosed in 38769 publication, although problems such as warpage of the record due to changes in temperature and humidity do not occur, the print display portion is the central non-sound groove portion of the record,
The display is small, and it becomes difficult to view when displaying a large amount of information. Further, since the print display portion is the same surface as the surface on which the sound groove is formed, there is a problem that it may damage the unprotected sound groove forming surface during printing.

[Problems to be Solved by the Invention] An object of the present invention is to provide an optical disk which has a sufficiently large display section and is capable of reliable and accurate display in view of the above-mentioned problems.

[Means for Solving the Problem] In order to achieve this object, the present invention provides a transparent synthetic resin substrate having a recording surface on which information is recorded, a reflective layer formed so as to cover the recording surface, A protective layer formed so as to cover the reflective layer, and in an optically readable optical disc, the protective layer formed on the reflective layer is directly formed on the surface of the recording surface after the protective layer is formed. It is characterized in that items related to information are displayed by printing.

[Operation] In the case of such a configuration, after the protective layer formed on the reflective layer is formed, the blank surface of the disc is used by directly printing the display of the information related to the recorded information on the surface. Then, the recorded contents can be displayed sufficiently and accurately.

[Example] An example of the present invention will be described below with reference to the drawings.

In the figure, reference numeral 1 indicates the entire optical disc, which has a structure in which, as is well known in the art, a transparent synthetic resin substrate 2 serving as a disc main body is provided with a minute recess called a pit 3 on one side thereof. The formed and digitized signal is recorded. A reflection layer 4 formed of an aluminum thin film or the like is formed on the substrate 2 so as to cover the recording surface formed by the pits 3, and the laser is incident from the other surface (signal reading surface) of the substrate 2. A beam is used to optically record and reproduce a signal.

In the present invention, the protective layer 5 is formed so as to cover the surface of the reflective layer 4, and on the surface of the protective layer 5 thus formed, as the display 6 of the items directly related to the recorded information, For example, as shown in FIG. 1, song name 6a, singer name 6b,
The display of lyrics 6c, record company name 6d, etc. is provided by printing.

If necessary, another print protective layer 7 may be further coated on the surface of the protective layer 5, and the protective layer 5 and the print protective layer 7 may be colored so that the recorded music May be distinguished by genre, for example, by symphony, opera, solo piece, and by color classification.

Further, a color ring 8 (see FIG. 3) may be provided on the protective layer 5 or the print protective layer 7 for each song title or singer recorded on the optical disc 1 for convenience of reproduction.

Furthermore, as shown in FIG. 4, a display 6 showing recorded contents is provided in a non-recording area F on the signal reading surface side corresponding to the signal recording area E on the signal recording surface side of the optical disc 1, and
The peripheral portion of the optical disk 1 is made thicker than the area F, and when the optical disk 1 is placed on a flat surface, if the area F is not in contact with the flat surface, the printing surface will not be worn, so the print protection layer 7 is covered. There is no need to do it.

[Effects of the Invention] As described above, according to the optical disc of the present invention, after the protective layer formed on the reflective layer is formed, it is possible to directly record the recorded information on the surface of the protective layer. Since the display is provided by printing, deformation of the disc can be prevented, and a sufficiently large display portion can be secured by utilizing the protective layer surface, that is, the blank surface, and clear and accurate display can be performed.

[Brief description of drawings]

1 is a plan view of an optical disk according to the present invention, FIG. 2 is an enlarged sectional view taken along line II-II of FIG. 1, FIG. 3 is a plan view showing an example of color coding, and FIG. 4 is a signal recording surface of the optical disk. FIG. 3 is a plan view showing a signal reading surface and a signal reading surface in comparison. 1 ... Optical disc, 2 ... Synthetic resin substrate, 3 ... Pit, 4 ... Reflective layer, 5 ... Protective layer, 6 ... Display (print), 6a ... Song title, 6b ... Singer name, 6c ... … Lyrics, 6d ……
Record company name, 7 ... Print protection layer, 8 ... Color strip,
E: Signal recording area, F: Non-recording area.

 ─────────────────────────────────────────────────── --- Continued from the front page (56) References JP-A-56-19531 (JP, A) JP-A-57-143701 (JP, A) JP-A-56-19532 (JP, A) JP-A-53- 73101 (JP, A) JP 53-143203 (JP, A) Actual opening 49-38769 (JP, U) Actual opening 49-142201 (JP, U) Actual opening 57-49733 (JP, U) Actual Open Sho 57-91188 (JP, U) Actual Open Sho 57-138192 (JP, U) Actual Open Sho 57-122032 (JP, U) Japanese Patent Sho 57-4973 (JP, B2) Japanese Official Sho 61-42315 (JP, B2) JP 60-28041 (JP, B2) JP 52-32931 (JP, B2) JP 40-9070 (JP, Y1) JP 37-22106 (JP, Y1) JP Public Sho 60-28997 (JP, Y2) Actual Public Sho 63-27298 (JP, Y2) Actual Public Sho 60-23769 (JP, Y2) Actual Public Sho 61-34585 JP, Y2)

Claims (1)

[Claims] 1. A transparent synthetic resin substrate having a recording surface on which information is recorded, a reflective layer formed so as to cover the recording surface, and a protective layer formed so as to cover the reflective layer. ,
In an optically readable optical disc, after the protective layer formed on the reflective layer is formed, the surface of the protective layer is directly printed with a display of matters related to the information on the recording surface. Optical disc.