JPS61153849A - Optical disk - Google Patents

Abstract

PURPOSE:To obtain an optical disk which has no error in recording and reproduction even in long-period use by forming an optical disk of plural circular disk having a hollow part between the substrate across spacers with recording layers inside, and fitting the outer peripheral part spacer of the optical disk between the substrates and adhering it to both surfaces of the substrates. CONSTITUTION:The fitting type outer peripheral part spacer 10 is adhered to both an internal surface 11 and an outer peripheral 12 of substrates 1 so that the sectional shape of the optical disk is as illustrated. The adhesion area of the adhesion to both surfaces of the substrates 1 is increased, so there is no peeling of adhesion surfaces even in long-period use, and no dust sticks on recording layer surface, so errors in the recording and reproduction of information are eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to the structure of an optical disk used in an optical disk storage device.

(Prior art and its problems) Optical disk storage devices record and reproduce information by irradiating a rotating disk with laser light. There is an optical disc used for this purpose called an air sandwich type optical disc.

This disc has a hollow space inside, and usually consists of two circular substrates with a recording layer on at least one inner surface that can record information using laser light, and spacers on the outer and inner peripheries. It is glued together with the two in between. This structure prevents dust from scratching the surface of the recording layer from running around and adversely affecting recording and reproduction.

Conventionally, when such an air sandwich optical disk is used for a long time, errors in recording and reproducing information occur, which has been a problem.

FIG. 2 is a diagram showing the cross-sectional shape of a conventional optical disc.

A recording layer 2 is provided on one side of the resin substrate 10, and an inner peripheral spacer 41 is provided to form a hollow portion 3 with the recording layer 2 inside.
It has a structure in which a substrate 1 is bonded with an external spacer 5 interposed therebetween. Recording and reproduction are performed by condensing laser light onto the recording layer through a substrate on which the recording layer is provided. Conventionally, when such optical discs are used for a long time, errors occur in recording and reproducing information, which has been a problem.

(Object of the Invention) An object of the present invention is to provide an optical disc that is free from errors in recording and reproduction even when used for a long time.

(Structure of the Invention) The optical disc of the present invention includes a plurality of circular substrates including at least one circular substrate having a recording layer on the surface thereof, with a spacer interposed therebetween so that a hollow portion is formed between the substrates with the recording layer inside. In the air sandwich type optical disk having the above structure, the outer circumferential spacer fits into the circular substrate and is bonded to both surfaces of the circular substrate.

(Detailed Description of Configuration) The present invention solves the problems of the prior art by adopting the above-mentioned configuration.

The present invention will be explained below with reference to the drawings.

The inventor of the present invention investigated the cause of recording/reproducing errors due to long-term use, and found that this was due to the adhesion between the outer circumferential spacer and the circular substrate peeling off and dust adhering to the surface of the recording layer. This is because optical discs use both the inner and outer circumferential sides as recording areas in order to reduce the amount of change in the relative linear velocity between the laser beam and the recording layer, so the adhesion width of the outer circumferential spacer is This is because the structure is much smaller than the bonding width.

FIG. 1 is a diagram showing the cross-sectional shape of the optical disc of the present invention. A mating type outer peripheral spacer 10 is bonded to both the inner surface 11 and outer peripheral surface 12 of the substrate l.

By adhering on both sides of the substrate to increase the adhesion area in this way, it will not peel off even after long-term use, and since dust will not adhere to the surface of the recording layer, errors in recording and reproducing information will no longer occur.

(Example) Examples of the present invention will be described below.

5-Amino-8-(P-ethoxyanilino)-2,3-dicyano-1 is applied to the area from φ45i++* to φ114mm on an acrylic resin disk substrate with a guide groove of inner diameter 15 m, p outer diameter 120Illν, and thickness 1.2 mm. An 800X thick organic thin film containing 90 or more 4-naphthoquinone dyes was formed as a recording layer. These two single disks are φ45su
+Xφ16mX0.5fl acrylic inner circumferential spacer and disc gap part is φ120 shoulder×φ116mmml×0.
5 cod, outer end φ130MXφ120mX 3.3M,
The adhesive part with the outer circumference is φ120m1×φ11611XQ
, an air sandwich optical disk was fabricated using a 2 m long acrylic fitting type outer circumferential spacer divided into four parts, and bonding the inner circumferential spacer and the inner surface of the substrate and the outer circumferential spacer and both sides of the substrate with acrylic ultraviolet curing resin. did.

Even after the optical disc produced in this way was cycled 10,000 times from normal pressure environment to reduced pressure environment and from reduced pressure environment to normal pressure environment, the adhesive did not come loose, and even when the originally recorded part was played back, errors occurred. However, discs that were not bonded to the outside of the board did experience some friction, resulting in playback errors.

When an air sandwich optical disk was manufactured using an aluminum alloy spacer in the same manner as in Example 1, similar effects were obtained.

(Effects of the Invention) As is clear from the above embodiments, according to the present invention, an optical disc can be obtained that does not leave adhesive parts unbroken even when used for a long period of time, and is free from errors in recording and reproduction.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an optical disk according to an embodiment of the present invention, and FIG.
The figure is a sectional view of a conventional air sandwich type optical disk. In the figure, 1 is a substrate, 2 is a recording layer, 3 is a hollow part, 4 is an inner spacer, and 5p10 is an outer spacer.

Claims (1)

[Claims] An air sandwich type optical disk having a configuration in which a plurality of circular substrates each including at least one circular substrate having a recording layer on the surface are formed with a hollow part between the substrates with the recording layer inside through a spacer, An optical disc characterized in that an outer peripheral spacer fits into the circular substrate and is bonded to both sides of the circular substrate.