JPH0753130Y2 - Information carrier disc - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an information carrier disk, and more particularly to an information carrier disk having an air sandwich structure in which a resin burr and an adhesive do not protrude from an outer peripheral edge of an information carrier substrate.

[Common Technique] Generally, in an information carrier disk having an air sandwich structure, two information carrier substrates are concentrically arranged and bonded to each other via an annular inner peripheral spacer and an outer peripheral spacer.

An information recording film is formed on at least one surface of the information carrier substrate in a closed space formed between the opposed information carrier substrates. The information carrier substrate is usually molded by injection molding or injection compression molding using a thermoplastic resin such as polymethyl acrylate or polycarbonate resin.
Occurrence of resin burrs is unavoidable at the time of molding at the outer peripheral edge portion of the molded information carrier substrate which is in contact with the outer peripheral spacer.

On the other hand, the two information carrier substrates are generally adhered to the inner and outer peripheral spacers by using an ultraviolet curable adhesive, and the adhesive is inevitably squeezed out during the adhesion.

[Conventional technology]

A conventional information carrier disk is composed of two information carrier substrates, an inner peripheral spacer and an outer peripheral spacer.

Next, a conventional information carrier disk will be described in detail with reference to the drawings.

FIG. 2 is a sectional view showing an example of a conventional information carrier disk.

The information carrier disc shown in FIG. 2 comprises two information carrier substrates 1 ′, an inner peripheral spacer 2 and an outer peripheral spacer 3.

An information recording film 4 is formed on at least one surface of the information carrier substrate 1'in a closed space formed between the facing information carrier substrates 1 '. The outer peripheral end portion 5'of the information carrier substrate 1'has a sharp edge, and a resin burr 6'generated at the time of molding is present on the surface side in contact with the outer peripheral spacer 3.

At the outer peripheral edge 5'of the information carrier disk shown in FIG. 2, there is an adhesive 7'that has been extruded and hardened when the two information carrier substrates 1'and the outer peripheral spacer 3 are bonded.

[Problems to be solved by the device]

However, in the above-described conventional information carrier disc, since the outer peripheral edge of the information carrier substrate is basically formed with a sharp edge at the time of molding, the resin burr generated during molding is the outer peripheral edge of the information carrier substrate. It had the drawback of being more prominent and easier to fall off.

Further, when the outer peripheral spacer and the information carrier substrate are adhered, the adhesive that sticks out adheres to the resin burr protruding from the outer peripheral end of the information carrier substrate and is hardened, and the hardened adhesive is accompanied by the deformation of the resin burr. It had the drawback of falling off in the form of a film.

[Means for Solving the Problems]

In the information carrier disk of the present invention, two information carrier substrates are concentrically opposed to each other via an inner peripheral spacer and an outer peripheral spacer, and the information carrier substrates are enclosed in a closed space formed between the opposed information carrier substrates. In an information carrier disk having an information recording film formed on at least one surface, a step is formed at the outer peripheral ends of two information carrier substrates in contact with the outer peripheral spacer.

〔Example〕

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the present invention.

The information carrier disk shown in FIG. 1 comprises two information carrier substrates 1
And an inner peripheral spacer 2 and an outer peripheral spacer 3.

The information carrier substrate 1 has a step 8 formed at a part of the outer peripheral end portion 5 which is in contact with the outer peripheral spacer 3. The step 8 is basically formed when the information carrier substrate 1 is molded. The amount of the step 8 is, for example, when the information carrier substrate 1 has a diameter of 130 mm and a plate thickness of 1.2 mm,
It is preferable that the thickness is about 0.15 mm and the radius is about 0.2 mm.

Next, the effect of the step at the outer peripheral end formed on the information carrier substrate of the present invention will be described in detail.

By forming the step 8, the generation of the resin burr 6 at the outer peripheral end of the sharp edge of the information carrier disk during molding was significantly reduced, and it did not protrude from the outer peripheral end 5.

Further, in the space formed by the step 8, it is possible to enclose the adhesive that has hardened and is hardened when the outer peripheral spacer 3 and the information carrier substrate 1 are bonded.

Peripheral spacer 3 for information carrier substrate 1 with a diameter of 130 mm
The outer peripheral edge of the information carrier substrate 1 is formed by forming the step 8 of about 0.15 mm in the plate thickness direction and about 0.2 mm in the radial direction on the outer peripheral edge portion 5 which is in contact with and the outer diameter dimension of the outer peripheral spacer 3 is 129.6 mm. The protrusion of the resin burr 6 and the adhesive 7 from the portion 5 was completely enclosed in the stepped space, and the manufacturing process of the information carrier disk had no problem when the information carrier disk was actually used.

[Effect of device]

The information carrier disk of the present invention contacts with the outer spacer 2
By forming a step at the outer peripheral edge of the information carrier substrate, the resin burr generated during the molding of the information carrier substrate is pressed inward from the outer peripheral edge of the information carrier substrate, and when the outer peripheral spacer and the information carrier substrate are bonded. Since the adhesive that has bulged out and hardened can be enclosed in the stepped space, there is an effect that the resin burr and the bulging of the adhesive can be substantially eliminated from the outer peripheral edge of the information carrier substrate.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG. 2 is a sectional view showing a conventional example. 1, 1 '... Information carrier substrate, 2 ... Inner peripheral spacer, 3 ...
Outer peripheral spacers, 4 ... information recording film, 5, 5 '... outer peripheral end, 6, 6' ... resin burr, 7, 7 '... adhesive, 8 ... step.

Claims (1)

[Scope of utility model registration request] 1. An inner peripheral spacer, an outer peripheral spacer, a pair of information carrier substrates adhered to the inner peripheral spacer and the outer peripheral spacer by an ultraviolet curable adhesive, the inner peripheral spacer and the outer peripheral spacer. Information recording films are formed on the respective surfaces in confined spaces which are concentrically opposed to each other and are formed between the opposed surfaces, and each of the pair of information carrier substrates has a step at the outer peripheral end in contact with the outer peripheral spacer. An information carrier disk characterized by being formed with.