JPS6238542A - Optical disc with ventilation holes - Google Patents

Abstract

PURPOSE:To extend the life of an optical disc by providing an air hole piercing a spacer or both the spacer and a transparent substrate. CONSTITUTION:Spacers 3 and 3' and substrates 1 and 1' are fixed to each other by adhesion to constitute an optical disc. Plastics, glass, or the like is used as materials of transparent substrates, and a methyl methacrylate, a polycarbonate, a polystyrene, an epoxy resin, or the like is used as plastics. The diameter of the air hole is 0.2-4mm, and preferably, 0.5-1.5mm diameter is effective, and the number of air holes is one at least. Though restrictions are not especially put on the position where the air hole is provided, air holes 6-9 are specified as the example in the figure, and penetration of dust or the like due to rotation of the disc is prevented if the air hole is opened to the outside peripheral surface, and it is preferable to provide the air holes symmetrically. Thus, the life of the disc is extended considerably.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an optical disk, and more particularly to an optical disk having a structure in which a spacer or a transparent substrate and a spacer have ventilation holes, resulting in a significantly longer life.

[Prior art and its problems]

Optical disks have attracted attention because they have a larger capacity than conventional magnetic disks and are easier to handle, but in recent years a high degree of dimensional accuracy has been desired due to the demand for higher density optical disks.

[Problem that the invention seeks to solve]

An optical disk with a hollow sand structure having an internal space is stable under normal environments due to its structure, but due to changes in the environment, the air sealed in the internal space expands or contracts.
Stress concentrates on the fixed portion, causing deformation of the substrate or, in the worst case, peeling of the fixed layer.

[Means for solving problems]

As a result of various studies on the causes of the above, it was discovered that the above drawbacks could be largely eliminated by changing the internal conditions of the optical disk in response to changes in the external environment, and thus completed the present invention. It has arrived.

That is, the present invention forms a recording material layer on at least one transparent substrate, and fixes the recording material layer with the formed surface facing the other substrate by providing spacers on the outer and inner peripheries. The optical disc has a structure in which a space is formed between the spacers, and the optical disc is characterized in that it has a spacer or a ventilation hole passing through both the spacer and the transparent substrate.

The optical disc in the present invention is, for example, one in which a recording material is provided on at least one of both transparent substrates and is integrated via a spacer, an example of which is shown in FIG. . In Fig. 1, 1 and 1' are transparent substrates, 2 and 2' are recording material layers, 3 and 3' are spacers,
4 is an air layer, spacers 3, 3' and substrates 1, 1'
are fixed and adhered to each other to form an optical disk.

The transparent substrate used in the present invention is not particularly limited, but plastic, glass, etc. can be used, and as the plastic, known materials such as methyl methacrylate, polycarbonate, polystyrene, and epoxy resin can be used.As the recording material, known materials can also be used. , any commonly used methods can be applied, and there are no particular limitations.

In the present invention, it is desirable that the optical disc has ventilation holes to the extent that the main function of the optical disc is not impaired. That is, if the hole diameter of the ventilation hole is too small, the ventilation will be poor, and if the hole diameter is too large, the rigidity of the optical disc will be insufficient. is valid. Further, the number of ventilation holes should be at least one, and depending on the situation, multiple ventilation holes may be provided.

The position where the ventilation hole is provided is not particularly limited, but
For example, specific examples include ventilation holes 6, 7, 8, and 9 provided in the locations shown in Figure 2.O6.7 is provided only in the spacer, and 8 and 9 are provided in the spacer and the transparent substrate, and the vent holes 6, 7, and 9 are provided in the locations shown in Figure 2. There is. In particular, the force of opening the holes in the outer circumferential direction prevents dirt and the like from entering from the rotating IC of the disk. Furthermore, it is preferable that they be provided symmetrically.

Furthermore, if you install a filter in the ventilation hole, you can prevent dust from entering. This is preferable because it can be expected to further extend the life of the optical disc.

A known filter is used in the present invention,
Any material that is commonly used as a filter may be used, and examples thereof include sintered bodies of plastic or metal, cotton and glass fibers, and the like.

Further, in FIG. 3, an example is shown in which a filter 10 is provided, but the filter can be prevented from falling off by making the diameter of the hole in the outer circumference of the optical disc smaller than the diameter of the hole in the filter installation part. In other words, when recording and playing back optical discs,
Since the optical disk is rotated in use, the filter may be pushed toward the outer periphery by centrifugal force and fall off, but the above structure prevents the filter from falling off.

[Example] Hereinafter, actual car examples of the present invention will be given and explained in more detail.

Example 1 A through hole with a diameter of φ is drilled at one location in the direction of lateral force using an electric drill in a flat inner peripheral spacer having a thickness of 3 m+3, an inner diameter of 35 φ, and an outer diameter of 120 φ. Using this spacer with holes, an optical disc of the present invention was prepared.

Example 2 A flat outer peripheral spacer with a thickness of 313N, an inner diameter of 295φ, and an outer diameter of 305φ is coated with KO, 5φ×1.
Two 0φ ventilation holes are opened horizontally at opposite positions, and 1φ
Filled with sintered plastic as a filter. Using this spacer with holes, an optical disc of the present invention was prepared.

Comparative Example An optical disc for comparison was prepared using a spacer without holes.

As described above, the original disks of Examples 1 and 2 and the optical disk of the comparative example were subjected to a humidity resistance test at 60° C. and exposed to 90% K in a 90% atmosphere, and the peeling state of the optical disks was observed and the recording/reproducing characteristics were measured. As a result, in the comparative example, partial peeling was observed after being left for 2 days.

On the other hand, the optical disc of the invention did not show any decrease in adhesive strength even after being left for 60 days, and was confirmed to have a long life.

In addition, the optical disc of the present invention filled with a filter has extremely small changes in recording/reproducing characteristics compared to an optical disc with only apertures, indicating that filling the filter with a filter is extremely effective in extending the life of the optical disc. Also confirmed.

〔Effect of the invention〕

As detailed above, the optical disc of the present invention has a much longer lifespan than conventional optical discs, and its industrial value is enormous. Furthermore, since the spacer has a ventilation hole passing through it, there is little variation in the hole diameter due to adhesive or the like.

[Brief explanation of the drawing]

FIGS. 1 and 2 are longitudinal sectional views showing an optical disc of the present invention, and FIG. 3 is a longitudinal sectional view showing an example in which the ventilation holes are filled with a filter. 1.11...Substrate, 2,2'...Recording material layer, 3...Subaser, 4...Vacancy layer, 5...Center Holes, 6, 7, 9... Ventilation holes, 1G... Filter patent applicant Asahi Kasei Industries, Ltd. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] forming a recording material layer on at least one transparent substrate;
In an optical disc having a structure in which the surface on which the recording material layer is formed faces another transparent substrate and is fixed by providing a spacer between the outer peripheral part and the inner peripheral part of each, the spacer or the spacer and the transparent substrate are penetrated. Optical disc characterized by having ventilation holes