JPH0264935A - Information recording medium - Google Patents

Abstract

PURPOSE:To improve recording and reproducing sensitivity by providing small pits penetrating a disk-shaped substrate consisting of a flexible resin to the non-recording region on the inner peripheral side of the substrate. CONSTITUTION:The non-recording regions 14a, 14b on the inner peripheral side of two sheets of the information recording disks provided with recording layers 12a, 12b between the non-recording regions 14a, 14b on the inner peripheral side of the flexible resin substrates 11a, 11b and the non-recording regions 16a, 16b on the outer peripheral side thereof are joined in an adhesive part 25 and the one resin substrate 11a is provided with the small hole 13. The small holes 13 are provided within 200 pieces to the non-recording regions 14a, 14b on the inner peripheral side and the diameter thereof is preferably within a 0.3 to 20mm range. The small holes 13 are the flow holes for the air and play the role of taking the air between a floating stable plate and the medium in order to stabilize the distance between the stable plate and the medium. The recording and reproducing sensitivity is improved in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to an information recording medium comprising a recording layer on which information can be read, written and/or erased by a laser.

More specifically, the present invention relates to an information recording medium in which the recording layer is formed on the surface of a flexible resin film.

[Technical Background of the Invention] In recent years, disc-shaped information recording media that use high energy density beams such as laser beams have been developed and put into practical use. This information recording medium is called an optical disk, and can be used as a video conference disk, an audio disk, a large-capacity still image file, and a large-capacity computer disk memory.

The basic structure of an optical disk is a disk-shaped transparent substrate made of plastic or the like, and a recording layer provided thereon from which information can be read, written, and/or erased. The surface of the substrate on which the recording layer is provided is coated with an undercoat layer or an intermediate layer made of a polymeric material in order to improve the flatness of the substrate, improve the adhesion with the recording layer, and improve the sensitivity of the optical disc. Sometimes it is provided.

In recent years, disc-shaped information recording media (optical discs) have been developed in which a flexible resin film is used as a substrate and the recording layer is formed thereon.

Information recording media using such flexible resin films are rotated at high speed to write, read, or erase information in the same way as conventional video discs, audio discs, etc. Since it is possible to form a film continuously by a method such as continuous coating, it has advantages such as easy mass production and low manufacturing cost.

On the other hand, information recording media using flexible resin films also
As with conventional information recording media using rigid substrates, various measures are taken to protect the recording layer to prevent dust from entering from the outside and scratches during handling. By providing a protective layer on the recording layer or bonding a protective film such as a resin film on the recording layer, it is possible to prevent the recording layer from deteriorating due to the intrusion of dust etc. from the outside. It is commonly practiced.

However, such a method of providing a protective layer or the like on the recording layer tends to deteriorate the inherent characteristics of the recording layer, and has problems such as a decrease in recording and reproducing sensitivity, for example.

As a method for preventing the adverse effects of dust and the like during QFQ generation, a system using a Bernoulli disk developed by IOMEGA of the United States for magnetic recording disks, for example, is known. This disk is made by joining two flexible disks with the recording layer on the outside through a hub on the inner circumferential side. During recording and reproduction, a Bernoulli plate is placed directly above the disk, and as the disk rotates, the amount of air flowing between the disk and the Bernoulli plate increases from the inner circumferential side of the Bernoulli plate. At the same time, air is sent between the two disks through ventilation holes provided on the inner circumferential sides of the two disks so that they do not come into contact with each other.

As the rotation speed of the disc increases, the space between the disc and the Bernoulli plate becomes negative pressure.

The disc is drawn toward the Bernoulli plate. Stable rotation without surface runout is achieved when the pressure between the disk and Bernoulli plate and the pressure from the outside world are in equilibrium. In this way, there is no occurrence of head crash,
Stable recording and reproduction that is resistant to vibrations can be performed, and dust and the like that have entered from the outside world can be removed from the system by air circulation between the disk and the Bernoulli plate.

However, in the above method, the recording layer of the disk may come into contact with the Bernoulli plate, particularly at the start and end of rotation of the disk, which may damage the recording layer. Furthermore, in the case of the above method, although it is possible to prevent the intrusion of dust and the like when the disc is in use, it is not sufficient to prevent the adhesion of dust and the like when the disc is not in use or in a stored state.

[Object of the Invention] The present invention provides an information recording medium consisting of two flexible resin substrates, which has excellent recording layer insulation ability such as prevention of intrusion of dust etc. from the outside, and has high recording sensitivity. The purpose is to

[Summary of the Invention] The present invention has the following features: [11] At least one of two disc-shaped substrates made of a flexible resin film having a hole in the middle is provided with a recording layer on the outside of the periphery of the hole and on the outer side of the hole. Two disk-shaped substrates made of flexible resin films are provided in an inner non-recording area and an outer non-recording area set inside the periphery, respectively, with the recording layer on the inside. The information recording medium is bonded at the non-recording area on the inner circumferential side.

An information recording medium, characterized in that a small hole is provided in a non-recording area on the inner circumferential side of at least one of the disk-shaped substrates, and: [2] a disk-shaped substrate with a hole in the center; At least one of the two disc-shaped substrates made of flexible resin film has a recording layer set outside the periphery of the hole and inside the outer periphery, respectively, in an inner non-recording area and an outer non-recording area. Two disc-shaped substrates made of flexible resin films provided in areas other than the recording area exceed the layer thickness of the recording layer in the inner non-recording area so that the recording layer is on the inside. The information recording medium is bonded via a thick spacer.

Preferred embodiments of the information recording medium [1] of the present invention are as follows.

l) The above-mentioned information recording medium, characterized in that the above-mentioned small holes are provided in a range of 1 to 200.

2) The information recording medium, wherein the diameter of the small holes is within the range of 0.3 to 20 mm.

3) The information recording medium, wherein the small holes are provided on concentric circles of the substrate.

4) The information recording medium described above, wherein the material of the substrate is polyolefin resin, cellulose acetate resin, polycarbonate, or polyester resin.

5) The above-mentioned information recording medium, wherein the thickness of the above-mentioned substrate is within a range of 20 to 200 JLm.

Preferred embodiments of the information recording medium [2] of the present invention are as follows.

l) The above information recording, wherein the spacer has a small hole penetrating a portion not used for bonding the substrates, and the number of the small holes is in the range of 1 to 100. Medium.

2) The spacer has a small hole penetrating the part not used for bonding the substrates, and the diameter of the small hole is 0.2 to 0.2.
The above information recording medium is characterized in that the information recording medium is within a range of 3 mm.

3) A non-recording area on the inner circumferential side of at least one of the substrates has small holes penetrating the substrate, and the number of the small holes is in the range of 1 to 200 and the diameter thereof is 0.3 ~20mm
The above-mentioned information recording medium is characterized in that it is within the range of.

4) The information recording medium described above, wherein the material of the substrate is polyolefin resin, cellulose acetate resin, polycarbonate, or polyester resin.

5) The above-mentioned information recording medium, wherein the thickness of the above-mentioned substrate is within a range of 20 to 200 gm.

The shape of the small hole is not particularly limited and may be any shape. Therefore, the diameter is the value obtained by converting the area into a circle.

Furthermore, the material and thickness of the disc-shaped substrates made of two flexible resin films may be the same or different.

[Detailed Description of the Invention] The information recording medium of the present invention is a so-called flexible optical disk, which basically consists of a flexible resin film having a recording layer on at least one of two substrates. It has a structure in which two disc-shaped substrates are joined at the inner circumferential side where the recording layer is not provided, with the recording layer facing inside.

The present inventor has conducted various studies in order to obtain a flexible optical disc that can prevent the intrusion and adhesion of dust and the like from the outside without deteriorating the recording sensitivity.

As mentioned above, in the past, for example, by providing a protective layer on the recording layer or bonding a protective film, defects such as scratches caused by dust entering from the outside or friction of the cartridge, optical head, etc. can be prevented. It is common practice to prevent this from occurring. Such a method of providing a protective layer or the like on the recording layer naturally deteriorates the inherent characteristics of the recording layer, and therefore tends to cause a decrease in recording and reproducing sensitivity.

In addition, in a system using a floating stabilizer called a Bernoulli disk developed by IOMEGA of the United States, a flexible disk is made by bonding two flexible substrates with the recording layer on the outside and the inner circumference side, and a Bernoulli plate is used. This enables stable rotation with no runout in one plane. Dust and the like that have entered from the outside world can be removed from the system by air circulation between the disk and the Bernoulli plate. However, although the above method is effective for magnetic recording systems that have a smaller recording density than optical disks (that is, the bit size of one bit is larger), it is not sufficient for optical recording that has a large recording density where the size of one bit is about lpm. Improvements were needed. When the above method is actually applied to optical recording, the recording layer of the disk comes into contact with the Bernoulli plate, especially at the start and end of rotation of the disk.

There are also problems in that the protection of the recording layer is not sufficient when the disk is not used or when it is stored.

The present invention is capable of preventing dust from adhering to the recording layer without deteriorating the inherent characteristics of the recording layer such as recording sensitivity, that is, without using a method of coating a protective layer or the like on the recording layer. Prevents scratches caused by friction with cartridges, etc.
This made it possible to improve reliability.

In other words, in the information recording medium of the present invention, as described above, basically two disc-shaped substrates made of a flexible resin film having a recording layer on at least one of the two substrates are used for recording. The layers are bonded on the inner side at the area where the recording layer is not provided.

In the information recording medium of the present invention, a small hole is provided in the non-recording area on the inner circumferential side of at least one of the disc-shaped substrates (information recording medium [l]), or: disc-shaped Two substrates are joined via a spacer having a thickness exceeding the thickness of the recording layer in the non-recording area on the inner peripheral side so that the recording layer is on the inside (information recording medium [2]
)It is necessary.

The configuration of the information recording medium of the present invention will be explained in detail with reference to FIGS. 1 to 3.

FIG. 1 is a cross-sectional view showing an example of the information recording medium [11] which does not have a spacer according to the present invention. Non-recording areas 14a, 14b and outer non-recording area 16
A and 16b, two information recording disks each having recording layers 12a and 12b are placed in the inner non-recording area 14a.
and 14b are bonded to each other by an adhesive portion 15. A small hole 13 is provided in one flexible resin substrate 11a. It is preferable that the small holes 13 are provided in the non-recording area 14a and/or 14b on the inner peripheral side in the range of 1 to 200, and have a diameter of 0.3
The distance between the levitation stabilizer and the medium is preferably within the range of ~20 mm, and the small hole is preferably provided on a concentric circle of the substrate. Its role is to let in air to stabilize the structure.

Joint portion 15 in the non-recording area on the inner circumferential side of the substrates
The bonding may be done with adhesive, heat fusion,
This may be performed using ultrasonic fusion or the like.

As shown in FIG. 1, the information recording medium [11
When the substrate is not used for recording/reproducing, etc., since the substrate is a flexible resin film, the two substrates are connected to the recording layer 12a, 12b and/or the non-recording area 16 on the outer circumferential side.
They are in contact at points a and 16b. This makes it possible to prevent dust and the like from entering the recording layer from the outside.

The small holes 13 function to separate the two recording layers by supplying air between the two substrates during recording and reproduction. Here, in order to reduce the intrusion of dust and the like, it is preferable that the supplied air be filtered beforehand using a filter or the like.

In addition, the recording and reproducing of the information recording medium [11] is carried out by attaching the information recording medium to a recording and reproducing device and rotating it, thereby separating the two substrates by the action of air flow through the small holes and stabilizing the two substrates. This is done by rotating the information recording medium and irradiating the information recording medium with a laser beam. However, in order to obtain more stable rotation with less surface runout, it is preferable to provide the levitation stabilizer (Bernoulli plate) above or below the disk. , the pressure with the outside world can maintain a stable equilibrium relationship.

As will be described later, in the information recording medium of the present invention, even when a Bernoulli plate is used, the recording layer does not come into contact with the Bernoulli plate or the cartridge, and therefore the recording layer is hardly damaged.

FIG. 2 is a sectional view schematically showing an example of an information recording medium [2] having a spacer according to the L-legged invention.

FIG. 2 shows non-recording areas 24a and 24b on the inner circumferential side and non-recording area 26 on the outer circumferential side on flexible resin substrates 21a and 21b.
Two information recording disks having recording layers 22a and 22b are placed between the inner non-recording area 14a and the recording layers 22a and 26b.
and 14b, an information recording medium is shown which is bonded by adhesive parts 25a and 25b via a spacer 27 having a small hole 23.

The small hole 23 is provided in a portion of the spacer 27 that is not used for bonding the substrates, and passes through the spacer.

Preferably, the spacer is provided with 1 to 100 small holes, and the diameter thereof is preferably in the range of 0.2 to 3 tnm. Furthermore, the spacer is not provided with the small holes. , 1 to 2 in the non-recording area 24a and/or 24b on the inner peripheral side of the substrate similarly to the information recording medium [1].
It may be provided within the range of 00, and its diameter is 0.
．． Preferably, the diameter is within the range of 3 to 20 mm, and the small holes are preferably provided on concentric circles of the spacer or substrate.

In the information recording medium [2], the small holes are not necessarily required.The function of the small holes is to supply air between the two substrates during recording and reproduction. However, since the thickness of the spacer is greater than the total layer thickness of the two recording layers, air tends to enter between the two substrates. Therefore, the information recording medium [2] can obtain stable rotation even without the small holes.

When the small hole is provided in a spacer, it is sufficient that the small hole passes through the spacer, and the small hole may also penetrate both the spacer and the substrate.

The method of joining the two substrates at the inner non-recording area via a spacer may be performed using an adhesive, or
This may be performed using heat fusion, ultrasonic fusion, or the like.

As shown in FIG. 2, the information recording medium [2] of the present invention is as follows:
When the substrates are not used for recording/reproducing, etc., since the substrates are flexible resin films, the two substrates cover the outer non-recording areas 26a, 26b and/or the recording layer 12.
a and 12b are in contact with each other. This makes it possible to prevent dust and the like from entering the recording layer from the outside.

The small holes 23 function to separate the two recording layers by supplying air between the two substrates during recording and reproduction. Here, in order to reduce the intrusion of dust and the like, it is preferable that the supplied air be filtered beforehand using a filter or the like.

Recording and reproduction of the information recording medium [23] is carried out by attaching the information recording medium to a recording and reproducing device and rotating it once, thereby irradiating the information recording medium with a laser beam.

FIG. 3 is a sectional view schematically showing an example of a stable rotational state during recording and reproduction of the information recording medium [2] of the present invention.

FIG. 3 shows that the information recording medium [2] in the state shown in FIG. 2 when stationary is attached to the motor hub l of the recording/reproducing device and rotated, and at the same time two media are passed through the air supply pipe 2 through the small hole 23. Air is supplied between the substrates during rotation, and air flows between the Bernoulli plate 3 and the motor hub 1 at the same time as the rotation, resulting in a stable rotation state. That is, with the start of rotation of the information recording medium,
The two substrates are separated by the supply of air from the small hole 23, and as the rotation speed of the information recording medium increases, the air pressure between the Bernoulli plate and the substrate becomes negative, and the substrate 21a is drawn toward the Bernoulli plate 3. . And the board 21
When the pressure between a and the Bernoulli plate 3 and the pressure of the outside world are in equilibrium, the space between the two substrates becomes stable, and stable rotation without surface runout is obtained. FIG. 3 shows this stable rotational state.

The Bernoulli plate 3 is preferably provided above or below the disk in order to obtain stable rotation with less surface runout.

The information recording medium of the present invention performs not normal magnetic recording but optical recording, so a signal can be recorded on the recording layer by irradiating a laser beam from the substrate side. It is possible to adopt a different configuration. Therefore, even if a Bernoulli plate is used, the recording layer is on the inside, so the recording layer does not come into contact with the Bernoulli plate.

Therefore, it can be said that there is almost no damage to the recording layer.

Although FIG. 3 describes an example in which a small hole is provided in a spacer, for example, an information recording medium [11] without a spacer as shown in FIG. Even with the information recording medium [21] having small holes on the inner circumferential side, it is possible to obtain a rotating state in which the two recording layers are stably separated as shown in FIG. It is preferable to supply air forcefully as shown in Figure 3, but even if this is not done, the rotation of the disk will generate an air flow and the air will be supplied naturally. No supply is required.

Although FIGS. 1 to 3 illustrate a configuration in which a recording layer is provided on both of two flexible resin substrates, the same applies to a configuration in which a recording layer is provided only on one of the substrates. be able to. In the case of this single-sided recording layer, the laser beam can enter from the recording layer substrate side or from the opposing substrate (protective plate). In addition, the above explanation is 1
This describes specific aspects of the information recording medium of the present invention, and is not limited to the above-mentioned aspects.

Since any known resin film, recording layer, undercoat layer, etc. constituting the information recording medium of the present invention can be used, these will be briefly explained below.

Materials for the disc-shaped resin film used in the present invention include acrylic resin, vinyl chloride resin, polystyrene resin, polyamide resin, polyolefin resin (
(e.g., polypropylene, polyethylene), polycarbonate, cellulose acetate resin, polyester resin (e.g.,
(polyethylene terephthalate), and thermoplastic resins such as polyvinylidene chloride. Preferred are polyolefin resins, polycarbonates, and cellulose acetate resins. The thickness of the above board is 20~20
It is preferably within the range of 0 ILm.

Materials used for the spacer include acrylic resin,
Examples include thermoplastic resins such as vinyl chloride resins, polystyrene resins, polyamide resins, polyolefin resins (e.g., polypropylene, polyethylene), polycarbonates, polyester resins (e.g., polyethylene terephthalate), and polyvinylidene chloride. . Preferred are polyolefin resin I, polycarbonate or polyester resin. Further, the shape thereof may be a disk-like or ring-like shape, and preferably a projection is provided on the surface to be bonded to the substrate. The spacer is manufactured by a molding method such as injection molding.

On the surface of the substrate on which the recording layer is provided.

For the purpose of improving flatness, improving adhesive strength, and preventing deterioration of the recording layer, an undercoat layer (and/or intermediate layer) may be provided, and the materials for the undercoat M (and/or intermediate layer) include: For example, polymethyl methacrylate, acrylic acid
Polymer substances such as methacrylic acid copolymers, nitrocellulose, polyethylene, chlorinated polyolefins, polypropylene, and polycarbonates; UV-curable resins such as acrylic yarns; organic substances such as silane coupling agents; and inorganic oxides ( SiO,, A look 203!″1?
), inorganic tetrahydride (MgF2), and t. Using the above material, for example, a layer made of UV curable resin may be provided as an undercoat layer,
Furthermore, an inorganic oxide layer may be provided as an intermediate layer thereon, and one or more layers may be provided by combining the above materials as appropriate.

In the present invention, the recording layer formed on the information recording medium is of a type (write-once type or DRAW [Direct Read
After Write type) and type that repeatedly performs recording and erasing using magneto-optical recording or phase change (erasable type, that is, E-D RAW [
Erasable-old rect Read After
Write】! ! There is a lot.

Examples of materials used for the DRAW type recording layer include T.
e, Zn, In, Sn, Zr, An, Ti, Cu, Ge
, Au, Pt and other metals; Bi, As, Sb and other metalloids;
Semiconductors such as Si; and alloys thereof or combinations thereof can be mentioned. Compounds such as sulfides, oxides, borides, silicon compounds, carbides, and nitrides of these metals, semimetals, or semiconductors; and mixtures of these compounds and metals can also be used in the recording layer. The recording layer may further contain various known metals, semimetals, or compounds thereof as recording layer materials.

Alternatively, the recording layer may be made of a dye such as a cyanine dye (combined with a polymer binder if desired).

The recording layer may be a single layer or a multilayer, and the thickness of the recording layer is generally from 100 to 50 mm in terms of optical properties required for optical information recording.
The range is 500 or more, preferably 150-1000 or more.

Further, in the case of E-DRAW in which the recording layer utilizes phase change, a recording layer made of the following material that can cause a phase change due to temperature is provided. At this time, a light-absorbing substance may be dispersed and contained if necessary.

Examples of the phase change include a change between a crystalline state and an amorphous state, and a change between a compatible state and a phase-separated state.

An example of a substance that can cause a state change between a crystalline state and an amorphous state is S b ray-x T e x (30
< x < 60), S b 2S e, Te01 (0
<x<2), As-Te-Ge system, S n -Te
Mention may be made of metal and metalloid compounds such as -Se series. In addition, known metals, semimetals, and compounds thereof that undergo a state change between a crystalline state and an amorphous state can be used. Further, a typical example of a material capable of magneto-optical recording is an amorphous perpendicularly magnetized film made of a transition metal and a rare earth element. 11 Examples of transfer metals include F.
e, Co, etc., and rare earth elements such as Tb, Gd, and N.
Examples include b.

Furthermore, a typical example of a substance that can undergo a state change between a compatible state and a phase-separated state is a polymer blend consisting of a mixture of two or more types of polymers. However, a combination of a polymer and a hexamer may exhibit similar behavior, and such a composition is also included in the polymer blend in the present invention.

If the recording layer is made of a metal or the like, or if the substance that can cause a phase change is an inorganic substance such as the metal,
It can be formed on the substrate by vapor deposition, sputtering, or ion blasting on the substrate surface. The recording layer may be a single layer or a multilayer, but its layer thickness is generally 100" from the viewpoint of optical density required for optical information recording.
in the range 1500 X, preferably 150 = l
It is in the range of 000X.

In addition, when the recording layer is an organic compound such as a dye or the above-mentioned polymer blend, a coating solution is prepared by dissolving the substance and, if necessary, a light-absorbing substance in an appropriate solvent, and this coating solution is coated with a spin code method. It can be formed on a substrate by applying it to the surface of the substrate by a coating method such as a roll coating method and then drying it.

A tracking guide layer is preferably provided on the recording layer or between the substrate and the recording layer, especially to improve tracking performance during recording.

Examples of methods for forming servo marks and the like for tracking control on the tracking guide layer include molding using a photopolymer layer (2P method), lithography using a photographic emulsion, and the like.

Further, if desired, an adhesion layer made of a silane coupling agent or the like may be provided in order to improve the adhesion between the recording layer and the protective layer.

On the recording layer, on the tracking guide layer, or between the recording layer and the tracking guide layer, inorganic substances such as 5in2, MgF2, SnO□, UV curable resin, etc. are used to protect the recording layer physically and chemically. A protective layer made of an organic substance may be provided.

In addition, in order to improve the scratch resistance, moisture resistance, and prevention of deformation and deterioration of the recording layer on the substrate side or the surface opposite to the substrate, inorganic substances such as silicon dioxide, tin oxide, and magnesium fluoride may be used. A thin film may be provided.

Further, on the substrate side of the recording layer or on the surface opposite to the substrate, for the purpose of improving the S/N ratio during information reproduction and improving the sensitivity during recording.

A light reflecting layer made of metal such as An, Cr and Ni may be provided.

[Effects of the Invention] As described above, the information recording medium of the present invention basically consists of two disc-shaped substrates each made of a flexible resin film having a recording layer, and is arranged so that the recording layer is on the inside. It has a structure in which it is joined at a portion on the inner circumferential side where no recording layer is provided.

That is, when the information recording medium of the present invention is not used for recording and reproduction, the two substrates are in contact with each other at the non-recording area and/or the recording layer on the outer peripheral side. Thereby, it is possible to prevent dust and the like from entering the recording layer from the outside.

In addition, during recording and reproduction, the two substrates are rotated and separated using air circulation, so there is nothing covering the recording layer, and the sensitivity can be increased by irradiating the recording layer with laser light from the substrate side. It is possible to obtain the excellent characteristics inherent in the recording layer without any deterioration.

In particular, when a rotating floating stabilizing plate (Bernoulli plate) is provided above or below the disk during recording and reproduction, stable rotation with less surface runout can be obtained. Therefore, there is no contact between the recording layer and the Bernoulli plate, and it can be said that the recording layer is hardly damaged even when the Bernoulli plate is used.

Therefore, it can be said that the information recording medium of the present invention is an information recording medium that can prevent the intrusion and adhesion of dust from the outside without deteriorating the recording sensitivity, and is hard to be damaged.

[Brief explanation of the drawing]

FIG. 1 shows an information recording medium without a spacer according to the present invention [
1] is a sectional view showing an example. FIG. 2 shows an information recording medium [2] having a spacer of the present invention.
FIG. 1 is a sectional view showing an example of FIG. FIG. 3 is a cross-sectional view of an example showing a stable rotational state during recording and reproduction of the information recording medium [2] of the present invention. Motor hub: l Air supply pipe = 2 Bernoulli plate = 3 Flexible resin substrate: 11a, 11b, 21a, 1b Recording layer: 12a, 12b, 22a, 22b Small hole = 13.
23 Non-recording area on the inner circumference side: 14a, 14b, 24a, 24b Non-recording area on the outer circumference side: 16a, 16b. 26a, 26b Adhesive part: 15.25a, 25b Spacer = 27

Claims (1)

[Claims] 1. At least one of two disc-shaped substrates made of a flexible resin film with a hole in the center has a recording layer on the outside of the periphery of the hole and on the inside of the outer periphery. Two disk-shaped substrates made of flexible resin films are provided in the inner non-recording area and the outer non-recording area, respectively, and are placed inside the area with the recording layer facing inside. An information recording medium joined at a non-recording area on the circumferential side, characterized in that a small hole passing through the disc-shaped substrate is provided in the non-recording area on the inner circumferential side of at least one of the disc-shaped substrates. Information recording medium. 2. At least one of two disc-shaped substrates made of a flexible resin film with a hole in the center, with a recording layer set outside the periphery of the hole and inside the outer periphery, respectively. Two disk-shaped substrates made of flexible resin films are provided in the non-recording area on the side and in the area other than the non-recording area on the outer circumference side, and the non-recording area on the inner circumference side is placed so that the recording layer is on the inside. An information recording medium in which the recording layer is bonded via a spacer having a thickness exceeding that of the recording layer.