JPS6089846A - Discoid optical information recording medium - Google Patents

Abstract

PURPOSE:To obtain an air sandwich type disc optical information recording medium having high mechanical strength by providing an outer circumferential spacer of specific shape between a couple of substrates. CONSTITUTION:The inside and outside of the circumference of a couple of the substrates 1, 1 are chamferred so as to contact an outer circumferential spacer 2 and the chamferred part of each substrate 1 and the outer circumferential spacer 2 are fixed by an adhesives 3. The outer circumferential spacer 2 is split into plural numbers in circumferential direction, the two substrates 1, 1 are held at a prescribed interval and assembled by inserting the spacer 2 from the circumference. Since the spacer 2 is fitted in a form of wedge, the mechanical strength of a recording medium is improved. Since the inner face 5 of each substrate 1 is not fixed by an adhesives but brought into contact with the outer circumference spacer 2 and the stress of the substrate due to deformation is absorbed due to deformation of the spacer 2, the mechanical strength is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a sandwich-type disc-shaped optical information recording medium in which a recording layer is provided on the surface of a disc substrate and information is optically recorded and reproduced.

BACKGROUND OF THE INVENTION An air sandwich type sealed disk is known, in which two disks each having a recording layer of gold (ζ4), an organic dye, etc. provided on a disk-shaped substrate made of plastic or the like are adhered via a spacer. For example, if we consider a disk with a radius of 100 cm as a disk-shaped recording medium, the information recording area has a radius of 5
It is set in the range of 0 to 95 gourds. Therefore, when using an air-sand inch type sealing structure, the width of the circumferential spacer can be made sufficiently wide, but the width of the outer circumferential spacer cannot be made very wide, resulting in poor adhesive strength at the outer circumferential portion.

Conventionally, as shown in FIG.
Although a rectangular surface has been proposed, since the adhesive portion 6 has the simplest shape, there are problems in that the strength is poor and positioning cannot be performed without a jig. Further, as an improved version of this, a structure as shown in FIG. 2 has been proposed (see Japanese Patent Laid-Open No. 172541/1983). In this case, the adhesive part 3 is in two directions, parallel and perpendicular to the substrate 1.
The bonding area is almost the same as that shown in FIG. 1, but the strength is significantly improved.

Furthermore, positioning is possible due to the fitting structure. however.

As mentioned above, since it has adhesive surfaces in two directions, there is a problem in that it is troublesome to supply adhesive.

In addition, it is preferable to use resin as the substrate material from the viewpoint of ease of handling, but in this case, the substrate deforms such as warping due to the influence of temperature or humidity, resulting in stress at the joint between the substrate and the spacer. There is a problem that this occurs. moreover,
In conventional sealing structures, the substrate and spacer are completely fixed with adhesive, so there is no mechanical margin at the joint against deformation of the substrate, and a considerable portion of the stress is absorbed by the adhesive surface and adhesive. There is a problem in that the material is absorbed and this leads to a decrease in strength.

1-1 The present invention was made in view of the above problems, and its main purpose is to provide an air-sand inch disk-shaped optical information recording medium with high mechanical strength.

vinegar? ! SUMMARY OF THE INVENTION The present invention uses a circumferential spacer divided into a plurality of pieces to absorb stress generated at the joint between the substrate and the spacer due to deformation of the substrate. In other words, the disk-shaped optical information recording medium of the present invention comprises a pair of substrates having a recording layer on one side of at least one of two disk-shaped substrates, with an inner spacer and an outer spacer arranged concentrically therebetween. In the disk-shaped optical information recording medium sealed with an adhesive so that the recording layer is on the inside, the outer circumferential spacer has a surface that contacts the inner and outer sides of the substrate pair, and the outer circumferential spacer has a circular surface. The substrate pair is divided into a plurality of pieces in the circumferential direction, and the substrate and the outer circumferential spacer are bonded to each other on the non-chamfered surface that contacts the inside of the pair of substrates.

Next, the present invention will be explained in detail with reference to FIGS. 3 to 5. The figure is shown as a partial cross-sectional view in which other components such as the inner spacer, the recording layer, the center hole, etc. are omitted in order to particularly emphasize the relationship between the outer spacer and the substrate of the present invention. First, in one embodiment of the present invention shown in FIG.
The inner and outer sides of the periphery 0 are chamfered so as to be in contact with the outer periphery spacer 2, and the chamfer of each substrate 1 and the outer periphery spacer 2 are fixed with an adhesive (adhesive layer) 6. The outer circumferential spacer 2 has a structure that can be divided into a plurality of pieces in the circumferential direction.

Assembly can be carried out by holding the two substrates 1, 1 at a predetermined distance and then fitting the length portion 1o into each side from the periphery. At this time, the spacer itself is wedged between the two substrates, thereby increasing the mechanical strength of the recording medium. Furthermore, when the two substrates try to move apart, the force of peeling acting on the adhesive layer 3 is smaller than that of the conventional example shown in FIGS. 1 and 2. In addition, in the example of the present invention, as shown in FIG. 6, the inner surface 5 of each substrate is merely in contact with the outer peripheral spacer 2 and is not fixed by adhesive, so that the substrate 1 is deformed and Even in the state shown in Fig. 4, the stress due to the deformation of the substrate does not concentrate on the adhesive layer as in the case of the conventional example, and the spacer 2 itself is deformed to create a gap 6 to absorb the stress due to the deformation of the substrate. can. ? ! In addition, this structure can prevent the adhesive from flowing out to the recording layer side. In the present invention, it is desirable to appropriately select the length shown by d in FIG. 4 so that the outer circumferential spacer 2 does not break due to deformation.

FIG. 5 shows another embodiment of the present invention, and FIG.
The only difference is the surface shape of the fitting portion between the substrate 1 and the outer circumferential spacer 2, and the other configurations are the same as shown in the figure. Here, an example of the assembly of the optical information recording medium of the present invention will be described. A pair of substrates having a recording layer on one side of at least one of the substrates 1 is connected to an inner spacer (not shown) arranged concentrically and A space 4 is formed so that the recording layer (not shown) is located inside through the outer circumferential spacer 2, and then the chamfered portion of the substrate 10 and the outer circumferential space 2 are fixed with an adhesive 3. A sandwich type optical H information recording medium can be assembled.

Further, as the recording layer in the present invention, any known recording member for optical information recording media can be used, and the recording layer is not limited to a specific one.

Typical examples include metal, metalloid, nonmetal, and dye layers. Further, the substrate may be a transparent substrate, typical examples of which include plastic and glass.

Further, in the case of the optical information recording medium of the present invention, the recording layer may be provided on two substrates in the case of a double-sided disk, and on one substrate in the case of a single-sided disk.

So far, we have mainly explained the shape of the outer spacer, which is one of the features of the present invention, but it goes without saying that any inner spacer, including known ones, can be used, and the type of recording layer and recording medium may also be used. Of course, various modifications can be made to the assembly method and the like within the scope of the present invention.

Effects The optical information recording medium of the present invention constructed as described above has high mechanical strength.

[Brief explanation of drawings]

1 and 2 are partial cross-sectional views of an optical information recording medium showing the relationship between a conventional outer circumferential strip and a substrate, and FIG.
5 through 5 are partial cross-sectional views of an optical information recording medium showing the relationship between the outer circumferential strip and the substrate according to the present invention. DESCRIPTION OF SYMBOLS 1... Substrate, 2... Outer periphery spacer, 6... Adhesive layer. 4... Space, 5... Non-adhesive surface, 6... Gap due to deformation.

Claims (1)

[Claims] A pair of substrates having a recording layer on one side of at least one of the two disc-shaped substrates is coated with an adhesive through an inner circumferential spacer and an outer circumferential spacer arranged concentrically so that the recording layer is on the inside. In the disk-shaped optical information recording medium inserted using the disk-shaped optical information recording medium, the outer circumferential spacer has a surface in contact with the inner and outer sides of the substrate pair, and the outer circumferential spacer is divided into a plurality of pieces in the circumferential direction, and It is characterized in that the substrate and the outer spacer are bonded to each other on the outer surface that contacts the inner side of the pair of substrates. Optical information recording medium.